HomeMy WebLinkAbout14. 22-519DECEMBER 13, 2022 22-519 RESOLUTION
(CARRIED________LOST________LAID OVER________WITHDRAWN________)
PURPOSE: APPROVE CITY-WIDE STORM WATER QUALITY
MANAGEMENT PLAN
INITIATED BY: DEPARTMENT OF PUBLIC WORKS
WHEREAS, the City of Oshkosh storm water discharge quality is regulated under
a Wisconsin Department of Natural Resources issued Municipal Separate Storm Sewer
System (MS4) permit; and
WHEREAS, in 2008 the City completed a City-Wide Storm Water Management
Plan that was updated in 2014 to be in compliance with NR 151.13 Developed Urban Area
Performance Standards for Total Suspended Solids (TSS); and
WHEREAS, the 2022 Storm Water Management Plan builds upon the information
generated during the 2014 Plan with updated changes that could assist the City in moving
towards compliance with all TMDL-pollutant targets identified in the City’s MS4 permit.
NOW, THEREFORE, BE IT RESOLVED by the Common Council of the City of
Oshkosh that the attached City-Wide Storm Water Quality Management Plan is hereby
approved.
I:\Engineering\Tracy Taylor\Memos to Mayor & Common Council\2022\Appr City-Wide SWMP_12-
8-22.docx Page 1 of 2
TO: Honorable Mayor and Members of the Common Council
FROM: Justin Gierach, Engineering Division Manager / City Engineer
DATE: December 8, 2022
RE: Approve City-Wide Storm Water Quality Management Plan
BACKGROUND
The City of Oshkosh’s (City’s) storm water discharge quality is regulated under a
Wisconsin Department of Natural Resources (WDNR) issued Municipal Separate Storm
Sewer System (MS4) permit. The permit was originally issued in 2006, re-issued in 2014,
and the third permit term began on May 1, 2019. The permit requires the City to conduct
various storm water management programs geared towards reducing storm water
pollutants from entering into the Upper Fox/Wolf River and Lower Fox River Basins.
The City’s MS4 permit references the Total Maximum Daily Load (TMDL) for Total
Phosphorus (TP) and Total Suspended Solids (TSS) in the two (2) Basins for storm water
pollution reduction targets. Appendix C of the City’s 2019 MS4 permit specifies a
schedule and requirements for the City to meet the TMDL pollution reduction
requirements by reachshed. A reachshed is a segment of a specific watershed. Within
the City-permitted MS4 area, there are four (4) reachsheds (Sawyer Creek, Lake Butte des
Morts, the Fox River, and Lake Winnebago) within the Upper Fox/Wolf River Basin and
one (1) reachshed (Neenah Slough) within the Lower Fox River Basin.
In 2008, the City completed a City-Wide Storm Water Management Plan to evaluate
storm water discharge quality on a city-wide basis. That plan was updated in 2014 to
assess compliance with NR 151.13 Developed Urban Area Performance Standard for TSS.
This 2022 Storm Water Quality Management Plan builds upon the information generated
during the 2014 Plan, updates models based on changes in development conditions, and
evaluates additional Storm Water Management Practices that could assist the City with
continuing to move towards compliance with all TMDL-pollutant targets.
I:\Engineering\Tracy Taylor\Memos to Mayor & Common Council\2022\Appr City-Wide SWMP_12-
8-22.docx Page 2 of 2
ANALYSIS
Under current Storm Water Management Practices, the City meets the TSS reduction
goals in three (3) (Lake Butte des Morts, the Fox River, and Lake Winnebago) of the five
(5) reachsheds and, based upon future development, can meet reduction goals in the
fourth (Neenah Slough) reachshed. With the implementation of this Plan, the City will
meet TSS reduction goals in the fifth (Sawyer Creek) reachshed.
The implementation of this Plan does not meet, nor does the plan identify, a way to
achieve the 85.6% TP reduction vs. “no controls” goal for the Upper Fox/Wolf TMDL
Basin. The implementation of practices from this Plan will be a step towards compliance
and reduce the required TP-reduction gap. The reduction target is extremely aggressive
and would require advanced treatment of storm water runoff that is technologically a
challenge and can be extremely costly. Based upon other statewide-approved TMDL’s,
compliance will be required in ten (10) permit cycles or fifty (50) years, with interim goals
along the way. Due to the length of permit compliance timeframe, all parties within the
storm water industry are hopeful that technology and practices will advance to allow
higher levels of treatment than is currently available.
FISCAL IMPACT
This resolution has no fiscal impact, however, future CIP projects highlighted in this Plan
will be evaluated through the CIP planning process and will have fiscal impact.
RECOMMENDATIONS
The Storm Water Utility Appeals Board and Staff recommends approval of the City-Wide
Storm Water Quality Management Plan.
Approved:
Mark A. Rohloff
City Manager
JLG/tlt
250 East Wisconsin Avenue, Suite 1600
Milwaukee, WI 53202-4203
T: 414.273.8800
City of Oshkosh
Stormwater Quality Management Plan
Prepared for
City of Oshkosh
Oshkosh, WI
November 14 , 2022
ii
Oshkosh SWMP Final
Table of Contents
List of Figures in Appendix A ...................................................................................................................... iv
List of Tables ................................................................................................................................................ v
List of Abbreviations ................................................................................................................................... vii
Executive Summary ................................................................................................................................... viii
Introduction and Purpose of this Plan .............................................................................................. viii
Stormwater Management Plan Analysis Methodology .................................................................... viii
Summary of Results and Conclusions ................................................................................................ ix
1. Introduction .......................................................................................................................................1-1
1.1 NR 151 Developed Urban Area Performance Standard for Pollution Reduction. ..............1-1
1.2 TMDL Program and Pollution Reduction Targets ..................................................................1-2
1.3 Revisions to the City’s MS4 Permit ........................................................................................1-4
2. Project Setting ...................................................................................................................................2-1
2.1 Overview ..................................................................................................................................2-1
2.2 Defining the Project Area .......................................................................................................2-1
2.2.1 Excluded Areas .........................................................................................................2-1
2.2.2 Other Entities with MS4s .........................................................................................2-2
2.3 TMDL Reaches and Reachsheds ...........................................................................................2-2
2.3.1 Upper Fox/Wolf TMDL ..............................................................................................2-3
Sawyer Creek ..........................................................................................................................2-3
Lake Butte Des Morts .............................................................................................................2-3
Fox River - Lake Butte Des Morts to Lake Winnebago .........................................................2-3
Lake Winnebago .....................................................................................................................2-3
2.3.2 Lower Fox TMDL .......................................................................................................2-3
Neenah Slough .......................................................................................................................2-4
2.4 Land Use and Municipal Limits ..............................................................................................2-4
2.4.1 General Background ................................................................................................2-4
2.4.2 Data Sources and Methods .....................................................................................2-4
2.5 Precipitation ............................................................................................................................2-5
2.6 Soils .........................................................................................................................................2-5
3. Stormwater Pollution Analysis ..........................................................................................................3-1
3.1 Methodology ............................................................................................................................3-1
3.2 Results: “No Controls” Conditions .........................................................................................3-2
3.2.1 TMDL Reachshed Loads ..........................................................................................3-2
3.2.2 Non-City MS4 TMDL Reachshed Loads ..................................................................3-3
3.2.3 City MS4 Only TMDL Reachshed Loads ..................................................................3-3
3.3 Existing Management Conditions (“With Controls”) Analysis ...............................................3-4
City of Oshkosh Stormwater Quality Management Plan Table of Contents
iii
Oshkosh SWMP Final
3.3.1 Street Cleaning .........................................................................................................3-4
3.3.2 Catch Basins with Sumps ........................................................................................3-6
3.3.3 Grass Swales ............................................................................................................3-7
3.3.4 Regional SMPs ..........................................................................................................3-8
3.3.5 Non-Regional SMPs ..................................................................................................3-9
3.3.6 Results: “With Controls” Analysis ......................................................................... 3-11
3.3.7 Non-City MS4 TMDL Reachshed With Control Loads .......................................... 3-13
3.3.8 City MS4 Only TMDL Reachshed With Control Loads ......................................... 3-14
4. Alternative Stormwater Management Practices Evaluation ...........................................................4-1
4.1 Incorporation of Additional Existing Non-Regional SMPs .....................................................4-1
4.1.1 SMPs with O&M Agreements Not Found ................................................................4-1
4.1.2 Previously Unidentified Non-Regional SMPs ..........................................................4-2
4.2 Street Cleaning .......................................................................................................................4-3
4.3 Leaf Management...................................................................................................................4-3
4.3.1 Eligible Areas for Numeric Credit from Leaf Management ....................................4-3
4.3.2 Existing Leaf Management Program and WDNR Guidance Criteria......................4-5
4.3.3 Phosphorus Reduction Credit from Leaf Management .........................................4-6
4.4 Regional SMPs ........................................................................................................................4-6
4.4.1 Regional SMP Evaluation .........................................................................................4-8
4.4.2 Regional SMP Cost Considerations .........................................................................4-9
4.4.3 Regional SMP Feasibility Summary ...................................................................... 4-10
4.5 Enhanced Settling for Phosphorus Removal ..................................................................... 4-10
4.5.1 Enhanced Settling Site Selection & Performance Analysis ................................ 4-11
4.6 Engineered Swales .............................................................................................................. 4-13
4.7 Biofilters and Rain Gardens ................................................................................................ 4-13
4.7.1 Rain Gardens ......................................................................................................... 4-14
4.7.2 Biofilters ................................................................................................................. 4-14
4.7.3 Biofilter and Rain Garden Widespread Implementation Impacts & Summary .. 4-16
4.8 Projected Development Pollution Control .......................................................................... 4-17
4.8.1 Redevelopment/Mixed Development .................................................................. 4-19
4.8.2 New Development ................................................................................................. 4-22
4.8.3 Site Specific Analysis ............................................................................................. 4-26
4.9 Considerations for Other Potential SMPs ........................................................................... 4-30
5. Miscellaneous MS4 Permit Items ....................................................................................................5-1
5.1 Ordinance Review ...................................................................................................................5-1
5.1.1 Construction Site Pollutant Control .........................................................................5-1
5.1.2 Post-Construction Stormwater Management .........................................................5-1
5.2 MS4 Map Review ....................................................................................................................5-1
6. Implementation Plan .........................................................................................................................6-1
6.1 Implementation Plan Components ........................................................................................6-1
City of Oshkosh Stormwater Quality Management Plan Table of Contents
iv
Oshkosh SWMP Final
6.1.1 Existing Non-Regional SMPs – Additional Research and Action ...........................6-2
6.1.2 Leaf Management ....................................................................................................6-2
6.1.3 Regional Stormwater Management Practices ........................................................6-3
6.1.4 Enhanced Settling for Phosphorus Removal ..........................................................6-3
6.1.5 Municipal Code Modifications .................................................................................6-3
6.1.6 Incorporation of Non-Regional SMPs from Future Development ..........................6-4
6.1.7 Rain Gardens & Biofilters ........................................................................................6-4
6.1.8 Non-measurable Implementation Plan Components .............................................6-4
6.1.9 Implementation Plan Component Limitation and Opportunities ...........................6-5
6.2 Implementation Plan Results .................................................................................................6-6
Appendix A: Figures ................................................................................................................................... A-1
Appendix B: WPDES MS4 Permit & WDNR Guidance ............................................................................ B-1
Appendix C: Draft Memorandum of Understanding ................................................................................C-1
Appendix D: Airport Swale Testing Documentation ............................................................................... D-1
Appendix E: “With Controls” Analysis Additional Information ................................................................ E-1
Appendix F: Non-Regional SMPs with O&M Agreements Not Found Additional Information ............... F-1
Appendix G: Leaf Management Additional Information ......................................................................... G-1
Appendix H: Potential Regional SMPs Additional Information .............................................................. H-1
Appendix I: Biofilter / Rain Garden Analysis Additional Information ...................................................... I-1
Appendix J: Redevelopment / New Development Analysis Supporting Information ............................ J-1
Appendix K: Implementation Plan ........................................................................................................... K-1
List of Figures in Appendix A
Figure 1-1. TMDL Reachsheds
Figure 2-1. TMDL Excluded Areas
Figure 2-2. Other MS4 Areas within Analyzed Area
Figure 2-3. TMDL Land Use Category
Figure 2-4. WinSLAMM Soil Categories
Figure 3-1. Street Cleaning Zones
Figure 3-2. Catch Basin Areas
Figure 3-3. City Grass Swale Areas
Figure 3-4. Regional SMPs
Figure 3-5. Non-Regional SMPs
Figure 3-6. “No Controls” Total TP Load by Watershed
Figure 3-7. “With Controls” Total TP Load by Watershed
City of Oshkosh Stormwater Quality Management Plan Table of Contents
v
Oshkosh SWMP Final
Figure 3-8. “No Controls” TP Load per Acre by Watershed
Figure 3-9. “With Controls” TP Load per Acre by Watershed
Figure 4-1. Non-Regional SMPs with O&M Agreements Not Found
Figure 4-2. Previously Unidentified Non-Regional SMPs
Figure 4-3. Areas Eligible for Leaf Management Credit
Figure 4-4. City Trees by Size
Figure 4-5. Potential Regional SMP Locations
Figure 4-6. Potential Redevelopment Areas
Figure 4-7. Potential New Development Areas
List of Tables
Table ES-1. TMDL Reachshed Targets and Reductions ............................................................................ ix
Table 1-1. TMDL Reaches Receiving Oshkosh Stormwater Discharges and Corresponding Reduction
Requirements 1 ...................................................................................................................................1-4
Table 2-1. Areas Excluded from the Pollution Loading Analysis ............................................................2-2
Table 2-2. Area of Other MS4s within City of Oshkosh ...........................................................................2-2
Table 2-3. TMDL Categorized WinSLAMM Land Use ..............................................................................2-4
Table 2-4. USDA/NRCS Soil Hydrologic Groups and WinSLAMM Designation for Project Area ...........2-6
Table 3-1A. “No Controls” Pollutant Loading Results .............................................................................3-2
Table 3-1B. Other MS4s Within the City of Oshkosh Municipal Limits - “No Controls” Pollutant
Loading Results ..................................................................................................................................3-3
Table 3-1C. “No Controls” Pollutant Loading Results Excluding Other MS4s Within the City of
Oshkosh Municipal Limits ..................................................................................................................3-4
Table 3-2. Street Cleaning Program Details ............................................................................................3-5
Table 3-3. Parking Density and Controls .................................................................................................3-5
Table 3-4. Street Cleaning Program Pollutant Load Reduction Results ................................................3-5
Table 3-5. Catch Basin Pollutant Load Reduction Results .....................................................................3-6
Table 3-6. City Grass Swale Pollutant Load Reduction Results .............................................................3-8
Table 3-7. Regional SMP Pollutant Load Reduction Results .................................................................3-9
Table 3-8. Non-Regional SMP Pollutant Loading Results .................................................................... 3-11
Table 3-9A. “With Controls” TSS Reduction Results ............................................................................ 3-12
Table 3-9B. “With Controls” TP Reduction Results .............................................................................. 3-13
Table 3-10A. Other MS4s Within the City of Oshkosh Municipal Limits – “With Controls” TSS
Reduction Results ........................................................................................................................... 3-13
City of Oshkosh Stormwater Quality Management Plan Table of Contents
vi
Oshkosh SWMP Final
Table 3-10B. Other MS4s Within the City of Oshkosh Municipal Limits – “With Controls” TP Reduction
Results ............................................................................................................................................. 3-14
Table 3-11A. “With Controls” TSS Reduction Results Excluding Other MS4s Within the City of
Oshkosh Municipal Limits ............................................................................................................... 3-15
Table 3-11B. “With Controls” TP Reduction Results Excluding Other MS4s Within the City of Oshkosh
Municipal Limits .............................................................................................................................. 3-15
Table 4-1. Additional Non-Regional SMPs with O&M Agreements Not Found Summary .....................4-1
Table 4-2A. Additional Non-Regional SMPs with O&M Agreements Not Found Potential TSS Reduction
Results ................................................................................................................................................4-2
Table 4-2B. Additional Non-Regional SMPs with O&M Agreements Not Found Potential TP Reduction
Results ................................................................................................................................................4-2
Table 4-3. Area Eligible for Leaf Management Credit .............................................................................4-4
Table 4-4. Potential Phosphorus Reduction Credit (WDNR Numeric Credit Option #2) .......................4-6
Table 4-5. Potential Regional Stormwater Management Practices Performance Summary ...............4-9
Table 4-6. Potential Regional Stormwater Management Practices Cost Summary .......................... 4-10
Table 4-7. Potential Enhanced Settling Analysis Summary................................................................. 4-12
Table 4-8. Rain Garden Evaluation - Potential Annual Pollution Reductions (per 100 acres) .......... 4-14
Table 4-9. Biofilter Evaluation - Potential Annual Pollution Reductions (per acre) ............................ 4-15
Table 4-10. Biofilter/Rain Garden Cost Evaluation ............................................................................. 4-16
Table 4-11. Projected Development Pollution Control Scenarios ....................................................... 4-18
Table 4-12. Average Annual Redevelopment & Mixed Development Area ........................................ 4-20
Table 4-13. Redevelopment Analysis Summary .................................................................................. 4-21
Table 4-14. New Development Analysis Summary .............................................................................. 4-25
Table 4-15. Ceape/Otter Parking Lot Alternative Evaluation & Ordinance Scenario Compliance
Summary .......................................................................................................................................... 4-27
Table 4-16. Field Operations Facility Alternative Evaluation & Ordinance Scenario Compliance
Summary .......................................................................................................................................... 4-28
Table 4-17. The Wit New Development Alternative Evaluation & Ordinance Scenario Compliance
Summary .......................................................................................................................................... 4-30
City of Oshkosh Stormwater Quality Management Plan Table of Contents
vii
Oshkosh SWMP Final
List of Abbreviations
2008 Plan City of Oshkosh Citywide Stormwater
Management Plan and Ordinance
Development
2014 Plan 2014 City of Oshkosh Citywide
Stormwater Quality Management Plan
ac acre(s)
BC Brown and Caldwell
BRRTS Bureau for Remediation and
Redevelopment Tracking System
City City of Oshkosh
DPW Department of Public Works
EPA United States Environmental Protection
Agency
FWWA Fox-Wolf Watershed Alliance
GIS Geographical Information System
HSD hydrodynamic separation devices
Lower Fox Total Maximum Daily Load and
TMDL Watershed Management Plan for Total
Phosphorus and Total Suspended Solids
in the Lower Fox River Basin and Lower
Green Bay”
IDDE illicit discharge detection and
elimination
MDRNA Medium Density Residential No Alleys
MEP maximum extent practicable
MOUs Memorandums of Understanding
MS4 Municipal Separate Storm Sewer
System
N/A not applicable
NEWSC Northeast Wisconsin Stormwater
Consortium
NHI Natural Heritage Inventory
NPS nonpoint source
NRCS Natural Resource Conservation Service
O&M Operations and Maintenance
PAHs Polycyclic Aromatic Hydrocarbons
SCM Stormwater Control Measure (term used
interchangeably with “SMP”)
SMP Stormwater Management Practice (term
used interchangeably with “SCM”)
STH State Trunk Highway
SWMP Stormwater Management Plan
TMDL total maximum daily load
TP total phosphorus
TSS total suspended solids
UNPS&SW Urban Non-point Source & Storm Water
Upper Fox/ Total Maximum Daily
Wolf TMDL Loads for Total Phosphorus and Total
Suspended Solids Upper Fox and Wolf
Basins study
USDA United States Department of Agriculture
USEPA United States Environmental Protection
Agency
USGS United States Geological Survey
UW University of Wisconsin
WDNR Wisconsin Department of Natural
Resources
WinSLAMM Windows Source Loading and
Management Model
WisDOT Wisconsin Department of
Transportation
WLA waste load allocation
WPDES Wisconsin Pollutant Discharge
Elimination System
yr year
Throughout this document the terms “WPDES permit”, “Stormwater Permit”, and “MS4 permit” are used
interchangeably to refer to the Wisconsin Department of Natural Resources (WDNR) General Permit to Discharge
Under the Wisconsin Pollutant Discharge Elimination System (WPDES) Permit No. WI-S050075-3. This general permit
regulates all discharge from the Municipal Separate Storm Sewer System (MS4) owned and operated by the City of
Oshkosh.
viii
Oshkosh SWMP Final
Executive Summary
Introduction and Purpose of this Plan
The City of Oshkosh’s (City) stormwater discharge quality is regulated under a Wisconsin Department
of Natural Resources (WDNR) issued Municipal Separate Storm Sewer System (MS4) permit. The
permit was originally issued in 2007 and was most recently reissued in 2019 (WI-S050075-3). The
permit requires the City to conduct various stormwater management program elements geared
towards reducing stormwater pollution from its existing storm sewer system. Further details on the
City’s MS4 permit and regulatory drivers can be found in Section 1.
Stormwater quality management planning allows the City to assess compliance with specific numeric
requirements of the permit and to identify implementation measures to move towards full
compliance. Specifically, the City is obligated to move towards meeting total maximum daily load
(TMDL) reduction targets for total suspended solids (TSS) and total phosphorus (TP) for areas of the
City that discharge within the four reachsheds (waterway drainage areas) of the Upper Fox and Wolf
River Basin TMDL. Additionally, there is a small area of the City that discharges into a single
reachshed in the Lower Fox River Basin TMDL. Section 2 provides more information on the
reachsheds and the project setting.
The purpose of this plan is to use computer modeling following WDNR guidance to:
1. Update the “no controls” (unmanaged) pollutant load from all applicable areas of the City
2. Update the “with controls” (current managed) pollutant load
3. Evaluate and consider potential stormwater management practices (SMPs) that the City could
implement to further improve stormwater discharge quality
4. Develop an implementation plan that identifies specific practices, the timing of those practices,
and their impact on moving towards compliance with the TMDL reduction targets
Stormwater Management Plan Analysis Methodology
This study recalculated the “no controls” stormwater pollutant loads throughout the City using the
WinSLAMM (Source Loading and Management Model for Windows) version 10.4 computer model,
representing runoff conditions as if it was completely unmanaged by the City. Then, the impact of
existing stormwater management measures on discharge stormwater quality was calculated.
Management measures evaluated include street cleaning, grass swales, catch basins with sumps,
regional SMPs, and non-regional SMPs. Results are managed on a reachshed basis to allow
comparison to the TMDL reductions identified in the respective TMDL studies. Details on the “no
controls” and “with controls” evaluations are in Section 3.
Following the “no controls” and “with controls” analyses, a variety of potential stormwater
management measures were evaluated. These include:
• Enhancements to the City’s leaf collection program
• Construction of additional regional SMPs
• Augmenting existing or future SMPs with coagulant treatment systems to improve settling and
increase nutrient removal
• Implementation of rain gardens and biofilters to reduce pollutants from targeted areas
City of Oshkosh Stormwater Quality Management Plan Update Executive Summary
ix
Oshkosh SWMP Final
• Consideration of the impact of new development and redevelopment on progress towards
meeting TMDL reduction goals, including how ordinance changes could be impactful
Alternative stormwater practices evaluated are detailed in Section 4.
Summary of Results and Conclusions
Current Progress Towards TMDL Compliance
The results of the analysis can be seen in Table ES-1 which summarizes TSS and TP reductions in
comparison to the TMDL load reduction targets by reachshed (bold text indicates that TMDL
reachshed reduction targets are met or exceeded).
Table ES-1. TMDL Reachshed Targets and Reductions
Reachshed TMDL Target TSS
Load Reduction %
“With Controls” TSS
Reduction %
TMDL Target TP Load
Reduction %
“With Controls” TP
Reduction %
Upper Fox/Wolf TMDL
Sawyer Creek 58.4% 28.7% 85.6% 20.9%
Lake Butte des Morts 20% 23.2% 85.6% 18.3%
Fox River – Lake Butte des
Morts to Lake Winnebago 20% 38.3% 85.6% 28.6%
Lake Winnebago 20% 30.8% 85.6% 24.8%
Lower Fox River TMDL
Neenah Slough 52% 0% 40.5% 0%
Comparing the TMDL target reduction goals to the reductions calculated in the “with controls”
analysis results in the following observations:
• The City meets the TSS reduction goals in three of the five reachsheds. TP reduction goals are
not met for any of the reachsheds.
• The TP reduction requirements from the Upper Fox/Wolf TMDL are extremely high and
achievement of these reductions with conventional stormwater management practices is not
feasible.
Additionally, the area of the City in the Neenah Slough reachshed is small (35 acres total) and is
Winnebago County park land.
Implementation Plan for TMDL Compliance
Following the evaluation of potential practices as described previously and detailed in Section 4, the
City selected components for implementation. The implementation plan includes a mix of items that
provide specific and measurable improvements toward meeting the TMDL goals (such as new wet
detention ponds) and some that cannot be directly tied to a specific measurable improvement but
are instrumental in continuing the success of the City’s overall plan (such as obtaining additional
operation and maintenance agreements for private stormwater management practices). Full
implementation plan tables, located in Appendix K and Section 6, provide details on the selected
components.
City of Oshkosh Stormwater Quality Management Plan Update Executive Summary
x
Oshkosh SWMP Final
One plan element that was identified to help move towards implementation is the potential
modification of the City’s Municipal Code for post-construction stormwater management. The code
updates include requiring new development and redevelopment sites to meet higher TSS reduction
requirements and to incorporate TP reduction requirements. This is discussed further in Section 4.
Significant capital projects are generally timed to occur every five years (such as planning and
constructing a new wet detention pond) to coincide with City MS4 permit cycles. The plan, as
currently laid out, extends into the year 2054. The duration of this schedule is linked to the six
highest priority capital projects. Additional projects are identified for future implementation. The
results suggest that by the end of this planning period, the City will be in compliance with TSS TMDL
reduction targets for four out of five of the City’s reachsheds, with the exception being Sawyer Creek.
The City is also projected to comply with the TP TMDL reduction target for Neenah Slough. The plan
falls short of meeting TP reduction targets for the City’s reachsheds in the Upper Fox/Wolf TMDL.
1-1
Oshkosh SWMP Final
Section 1
Introduction
The City’s stormwater discharge quality is regulated under a WDNR issued MS4 permit. The permit
was originally issued in 2007 and was most recently reissued in 2019 (WI-S050075-3). The permit
requires the City to conduct various stormwater management programs including reduction of
stormwater pollution from its existing storm sewer system. See Section 1.3 for a discussion on
several important revisions contained in this most recent permit.
In 2008, the City completed a Citywide Stormwater Management Plan (SWMP) to evaluate
stormwater discharge quality on a citywide basis. That plan was updated in 2014 to assess
compliance with NR 151.13 Developed Urban Area Performance Standard for total suspended solids
(TSS). Details of the performance standard are included in Section 1.1 of this report. The 2014 Plan
indicated that the City had met and exceeded the required 20 percent TSS reduction. The 2014 Plan
also considered implications of future Total Maximum Daily Load (TMDL) requirements that the City
could face.
This stormwater management plan builds upon the information generated during the 2014 Plan,
updates models based on changes in development conditions (soils, land use, city limits, additional
stormwater management practices [SMPs], etc.), and evaluates additional SMPs that could assist
the City with continuing to move towards compliance with all TMDL pollutant targets. Stormwater
pollution analyses were conducted with a focus on compliance with the “Total Maximum Daily Loads
for Total Phosphorus and Total Suspended Solids Upper Fox and Wolf Basins” (Upper Fox/Wolf
TMDL) study that was approved by United States Environmental Protection Agency (USEPA) in
February 2020. Additionally, a small portion of the City is tributary to the Lower Fox River. For this
area of the City, the applicable pollutant targets are identified in the “Total Maximum Daily Load and
Watershed Management Plan for Total Phosphorus and Total Suspended Solids in the Lower Fox
River Basin and Lower Green Bay” (Lower Fox TMDL), which was approved by the EPA in March
2012. This report is partially funded by a WDNR Urban Non-point Source & Storm Water (UNPS&SW)
Program Planning Grant. The remaining funding is paid through the City of Oshkosh’s Stormwater
Utility.
The full TMDL reports can be found on the WDNR’s website at https://dnr.wi.gov/topic/tmdls/. This
plan fulfills the TMDL stormwater planning requirements for the City. The methodology, analytical
approach, and the results are described in subsequent sections of this document.
1.1 NR 151 Developed Urban Area Performance Standard for
Pollution Reduction.
The Developed Urban Area Performance Standard (NR 151.13) for MS4 permit holders has been in
place since October 2004, when the Administrative Code NR 151 Runoff Management requirements
were promulgated by the WDNR. This standard requires municipalities with MS4 permits to reduce
pollution from areas within the City that were developed as of October 2004. When this standard
was first put in place, the City was required to meet TSS pollution reductions from a “no controls”
condition of 20 percent by March 31, 2008, and 40 percent by March 31, 2013. These control levels
were applied to the City as a whole.
City of Oshkosh Stormwater Quality Management Plan Update Section 1
1-2
Oshkosh SWMP Final
Under state budget bill 2011 Wisconsin Act 32, two provisions were passed which directly impacted
the Developed Urban Area Performance Standard.
1. The March 31, 2013 deadline regarding the 40 percent TSS reduction requirement from existing
urban areas was removed. The requirement to meet the 20 percent TSS reduction is still in
force, as are all performance standards addressing new land development and land
redevelopment.
2. A second provision of 2011 Wisconsin Act 32 identified that where a permitted municipality had
achieved a reduction above the 20 percent TSS performance standard, all structural best
management practices in place on July 1, 2011, must be maintained to the maximum extent
practicable (no backsliding).
The pollution reduction analysis conducted under the 2014 Plan found that the City was achieving a
29 percent reduction in TSS (from a “no controls” condition). This means that the City complies with
the current NR 151.13 requirement, and the City must continue to maintain the existing
management measures.
Because the City meets the NR 151.13 pollution reduction targets, the remaining portions of the
plan will focus on TMDL compliance, and policies and procedures applicable to the WDNR’s TMDL
guidance.
1.2 TMDL Program and Pollution Reduction Targets
The Lower Fox TMDL and Upper Fox/Wolf TMDL reports establish Wasteload Allocations (WLAs) and
associated pollution reduction requirements for TSS and TP for each reachshed in the City of
Oshkosh. A “reachshed” is the watershed (drainage area) to an identified segment of a stream, river,
or other water body as defined in the TMDL document.
In 2012, the Lower Fox TMDL study established pollution reduction goals (TSS and TP) for
waterbodies within the study area limits. The City of Oshkosh was not identified in the TMDL study.
The TMDL study is a high-level study that utilized regional datasets and it was not able to account for
all detailed watershed information available. Detailed City mapping shows a small portion
(approximately 35 acres [ac] on the far northern end of the City of Oshkosh is tributary to the Neenah
Slough Reachshed in the Lower Fox TMDL). In 2020, the Upper Fox/Wolf TMDL study established
TSS and TP targets for four reachsheds in the city. Reachsheds and their corresponding required
reductions are found in Table 1-1 and can be seen graphically on Figure 1-1 located in Appendix A.
The two TMDL studies present the required reductions somewhat differently. The Upper Fox/Wolf
TMDL presents pollution reduction requirements for a reach as “Local”, “Downstream”, and “Total”
reductions from baseline loads. For example, in Table 6 of Appendix H of the Upper Fox/Wolf TMDL
report, the Sawyer Creek TMDL reach (TMDL Subbasin 30 in the Upper Fox/Wolf TMDL report) has a
“Local” reduction of 0 percent, “Downstream” reduction of 83 percent, and corresponding “Total”
reduction of 83 percent for TP allocated to the City of Oshkosh, all expressed as reductions from
baseline loads. (The importance of the word “baseline” will be addressed in a subsequent
paragraph.) The intent of this breakdown is to explain the amount of stormwater pollution reduction
that is needed to reduce the impairment of the “local” waterway (in this example Sawyer Creek), and
pollutant reductions must be made within the drainage area to Sawyer Creek (direct drainage
subbasin or from an upstream drainage area). The remaining reduction can be found from anywhere
within the drainage area for Lake Winnebago to meet more stringent downstream reduction
requirements. For the purpose of this study, it will be assumed that the City must meet the “Total”
reduction requirement for each reachshed and only those are presented in this report. Information
on TP and TSS allocations and reduction requirements for each reachshed are presented in
Appendices H and I, respectively, of the Upper Fox/Wolf River TMDL report document.
City of Oshkosh Stormwater Quality Management Plan Update Section 1
1-3
Oshkosh SWMP Final
The Lower Fox TMDL did not express reductions in the same manner as the Upper Fox/Wolf TMDL
report. The information is not expressed in terms of “Local” and “Downstream” but only the total
reduction from baseline is reported and required. Information on each reachshed is presented in
Section 6 of the Lower Fox River TMDL report document.
Furthermore, the required reductions reported in each of the two TMDL studies are represented as
reductions from baseline conditions. This is not the same as the “no controls” conditions that are
customarily used in citywide water quality studies in Wisconsin and described in WDNR guidance
documents. The two TMDL studies were required to assume that the NR 151 reductions of
20 percent for TSS (and a corresponding 15 percent for TP) were being met by the municipalities.
(See page 57 of the Upper Fox/Wolf TMDL report for a more detailed description and reasoning.)
This means that the actual reduction requirements from baseline are higher than those listed in
tables in the TMDL reports. For example, in the Neenah Slough reachshed, the Lower Fox TMDL
report (table on page 54) identifies a reduction of 40 percent from baseline loads of TSS is required
from Urban MS4 areas. In this case, the baseline assumes a 20 percent reduction in TSS has
already been achieved, so to calculate the reduction from “no controls”, the equation is:
20% + (0.80 * 40%) = 52%.
Using the prior example of Sawyer Creek in the Upper Fox/Wolf TMDL report, an 83 percent
reduction in TP is required from baseline loads from the Oshkosh MS4. In this case, the baseline
assumes a 15 percent reduction in TP has already been achieved, so to calculate the reduction from
“no controls”, the equation is:
15% + (0.85 * 83%) = 85.55% (say 85.6 % when rounded).
The pollution reduction targets in Table 1-1 are based on a “no controls” condition which is
consistent with the way NR 151 pollution reduction levels are established. The various receiving
waters are described further in Section 2.3.
It should further be noted that the 85.6 percent TP reduction goal established for Upper Fox/Wolf
TMDL reachsheds is very challenging. Research, such as from the University of Minnesota
St. Anthony Falls Laboratory, has found that the dissolved phosphorus fraction in typical urban
stormwater ranges from 25 to 50 percent, and higher dissolved fractions over 90 percent are not
uncommon. Many of the typical stormwater management measures mainly remove the particulate
forms of a pollutant and have less impact on the soluble form. Thus, even if 100 percent of the
particulate form of phosphorus is removed from all sources of stormwater, the treatment level would
still be short of the required reduction. To achieve the higher TMDL TP reductions, both the
particulate and soluble forms of phosphorus will need to be addressed.
City of Oshkosh Stormwater Quality Management Plan Update Section 1
1-4
Oshkosh SWMP Final
Table 1-1. TMDL Reaches Receiving Oshkosh Stormwater Discharges and Corresponding Reduction Requirements 1
TMDL Reach TMDL Report Identified
TSS Reduction 1
City Required TSS
Reduction 1
TMDL Report Identified
TP Reduction 1
City Required TP
Reduction 1
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 48% 58.4% 83% 85.6%
Lake Butte des Morts 0% 20.0% 83% 85.6%
Fox River-Lake Butte des
Morts to Lake Winnebago 0% 20.0% 83% 85.6%
Lake Winnebago 0% 20.0% 83% 85.6%
Lower Fox River TMDL Reachshed
Neenah Slough 40% 52.0% 30% 40.5%
1 Sources: “Total Maximum Daily Loads for Total Phosphorus and Total Suspended Solids Upper Fox and Wolf Basins” and “Total
Maximum Daily Load and Watershed Management Plan for Total Phosphorus and Total Suspended Solids in the Lower Fox River
Basin and Lower Green Bay”. See Section 1.2 for difference between TMDL Report and City Required TMDL reductions.
1.3 Revisions to the City’s MS4 Permit
The current WDNR General Permit to Discharge Under the Wisconsin Pollutant Discharge Elimination
System, WPDES Permit No. WI-S050075-3 (commonly referred to as the MS4 Permit), was made
effective as of May 1, 2019. The MS4 Permit regulates stormwater quality from the City’s stormwater
system and defines compliance requirements for meeting the TMDLs pollution reduction goals.
Important TMDL requirements that impact the City relative to Upper Fox/Wolf TMDL areas are
described in the MS4 Permit’s “Appendix C: MS4 Permittees Subject to a TMDL Approved After
May 1, 2019”. Because the City is not currently in compliance with TMDL reductions for all
reachsheds in the Upper Fox/Wolf TMDL, the City will need to follow section “C.4. TMDL
Implementation Plan”, as well as adhere to “C.5. Annual Reporting”
Additional requirements that impact the City relative to Lower Fox TMDL areas are described in the
MS4 Permit’s “Appendix A: MS4 Permittees Subject to a TMDL Approved Prior to May 1, 2014
including Applicable Updates”. Because the City is not currently in compliance with TMDL reductions
for the reachshed in the Lower Fox TMDL, the City will need to follow the most suitable path to
compliance based on options outlined in “A.5 Compliance Over Multiple Permit Terms”, as well as
adhere to “A.6 Reporting Requirements”.
The full WPDES General Permit with the referenced appendices is in Appendix B.
This Plan was prepared to meet applicable requirements of both appendices to the extent
practicable.
2-1
Oshkosh SWMP Final
Section 2
Project Setting
2.1 Overview
The City of Oshkosh is in northeastern Wisconsin, located within Winnebago County. The City is
situated on the Fox River between Lake Butte des Morts and Lake Winnebago. The US Census
Bureau reported a 2020 population of 66,816 for the City. The 2020 municipal boundary
encompassed over 27 square miles.
2.2 Defining the Project Area
The project area for compliance with the Upper Fox/Wolf and Lower Fox TMDLs involves analyzing all
applicable urban developed land as of the date of this study. For this purpose, the land use,
drainage, and management conditions, as defined on the data files provided by the City, are
considered current conditions. These files reflect conditions as of approximately July 7, 2020.
A WDNR policy memo “TMDL Guidance for MS4 Permits: Planning, Implementation, and Modeling
Guidance” (document number 3800-2014-04) issued October 2014, and recertified
September 16, 2019, clarified how municipalities should conduct their TMDL analysis. The
document describes areas that are required for inclusion in a study and areas that are optional for
inclusion (typically referred to as excluded areas). This policy memo can be found on the WDNR’s
website along with other MS4 modeling guidance documents at
https://dnr.wi.gov/topic/stormwater/standards/ms4_modeling.html.
2.2.1 Excluded Areas
The areas excluded from this TMDL analysis are identified as follows:
• Agricultural areas.
• Lands within the Wisconsin Department of Transportation (WisDOT) right-of-way that are
operated and maintained by WisDOT.
• Major open water features–specifically the Fox River, Sawyer Creek downstream of IH 41, Lake
Winnebago, and Lake Butte des Morts. Minor water features are included within their
surrounding land use category.
• Lands within the existing quarry located northwest of South Park Avenue (STH 44) that are
identified as an industrial area and are permitted under NR 216.
Table 2-1 lists components of the 2,519 ac excluded from the pollution loading analysis and not
subject to the MS4 Permit requirements. Figure 2-1 in Appendix A displays the locations of the
excluded areas.
City of Oshkosh Stormwater Quality Management Plan Section 2
2-2
Oshkosh SWMP Final
Table 2-1. Areas Excluded from the Pollution Loading Analysis
Exclusion Type Excluded Area (ac)
Agricultural 1,348
WisDOT 451
Open Water 603
Quarry - Permitted Industrial 117
Totals 2,519
Note: in some limited instances, an area may be eligible for exclusion
under multiple conditions but is only listed once in Table 2-1.
2.2.2 Other Entities with MS4s
Within the City of Oshkosh there are areas that belong to Winnebago County (County Highways,
parcels, and Wittman Airport) and the University of Wisconsin-Oshkosh. These entities also have MS4
permits. The City has cooperated with these entities on various stormwater management issues and
MS4 compliance. The City is in the process of developing Memorandums of Understanding (MOUs) to
define the roles and responsibilities of each entity. Draft version of MOUs with Winnebago County
(regarding County Highway areas) and University of Wisconsin (UW)-Oshkosh are included in
Appendix C. As part of these MOUs the City anticipates being responsible for managing pollutant
loads from any areas owned by these entities that are located within the City of Oshkosh. As part of
this report, areas from these entities are included within the analysis and the numbers reported in
tables. Additional tables are provided to allow the pollutant loadings from UW-Oshkosh and
Winnebago County areas to be considered separately. Winnebago County areas are divided into
three categories: (1) county highway areas, (2) Wittman Airport areas, and (3) county-owned parcels.
County-owned parcels are defined as parcels that are owned by Winnebago County and not single
family residential parcels. Single family residential parcels owned by Winnebago County were not
separately classified.
Table 2-2 lists the non-City entities and the associated area within the TMDL study area. Figure 2-2
displays the location of these areas.
Table 2-2. Area of Other MS4s within City of Oshkosh
MS4 Area (ac)
UW-Oshkosh 169
Winnebago County – Airport 830
Winnebago County - Highway 61
Winnebago County – Large Parcels 1,149
Totals 2,209
2.3 TMDL Reaches and Reachsheds
Land area within the City of Oshkosh drains to one of four impaired waters, either directly or
indirectly, through tributaries via storm sewers or open channels. Impaired waters are often broken
up into multiple segments (reaches) to better describe and categorize differing conditions within the
waterway. Land area that drains to these impaired waters are referred to as subbasins or
reachsheds.
City of Oshkosh Stormwater Quality Management Plan Section 2
2-3
Oshkosh SWMP Final
These water resources are briefly described in the following sections. The descriptions were obtained
from WDNR’s “Explore Wisconsin’s Waters” (http://dnr.wi.gov/water/default.aspx) and “Impaired
Waters Search” (https://dnr.wi.gov/water/impairedSearch.aspx) tools on the WDNR website.
Figure 1-1 in Appendix A displays the TMDL reachshed drainage areas within the City of Oshkosh.
2.3.1 Upper Fox/Wolf TMDL
Two of the impaired water reachsheds (Lake Butte Des Morts and Lake Winnebago) were recently
evaluated as part of the Upper Fox/Wolf TMDL study that was approved by the EPA in February
2020. Additionally, the TMDL considered the Fox River and Sawyer Creek which discharge into these
waterbodies.
Sawyer Creek
Sawyer Creek (associated with TMDL subbasin 30 in the Upper Fox/Wolf TMDL) is a 2.5-mile-long
tributary to the Fox River. The downstream portion flows through the City of Oshkosh and enters the
Fox River from the west, just south of Oshkosh Avenue (STH 21). Approximately 2,700 ac in the City
drain directly into Sawyer Creek.
Lake Butte Des Morts
Lake Butte Des Morts (associated with TMDL subbasin 73 in the Upper Fox/Wolf TMDL) is an
8,580-ac lake. The lake is predominantly northwest of the City and is the confluence of the Fox and
Wolf Rivers. The Wolf River enters the lake from the northwest and the Fox River enters from the
west. The Fox River leaves the lake on the southeast side, within the City of Oshkosh. Listed
impairments include low dissolved oxygen, eutrophication, and excess algal growth from TSS and TP.
Approximately 2,100 ac of the City drains into Lake Butte Des Morts on both the north and south
shores of the lake.
Fox River - Lake Butte Des Morts to Lake Winnebago
The Fox River, between Lake Butte Des Morts and Lake Winnebago, is approximately 3/4 of a mile
long and flows through the middle of the City of Oshkosh. This stretch of the river is impaired for
Acute Aquatic Toxicity by PAHs, however, this impairment was not addressed as part of the TMDL.
Numerous storm sewer outfalls along both sides of the river carry runoff from about 3,500 ac of the
City of Oshkosh into the river.
Lake Winnebago
Lake Winnebago (associated with TMDL subbasin 75 in the Upper Fox/Wolf TMDL) covers
approximately 206 square miles and is the largest lake in Wisconsin. The primary inlet to the lake is
the Fox River at Oshkosh, and its outlet is the Fox River at Neenah/Menasha downstream of the City
of Oshkosh. The lake level is controlled via locks and dam at Neenah/Menasha. The lake is listed by
the WDNR with numerous impairments including low dissolved oxygen, eutrophication, turbidity, and
excess algal growth from pollutants that include TSS and TP. About 1/2 of the City (7,000 ac) drain
directly to the lake through numerous storm sewers outfalls located on the eastern side of the City.
2.3.2 Lower Fox TMDL
One impaired water reachshed (Neenah Slough) that receives runoff from the City of Oshkosh was
evaluated as part of the Lower Fox TMDL.
City of Oshkosh Stormwater Quality Management Plan Section 2
2-4
Oshkosh SWMP Final
Neenah Slough
Neenah Slough is a stream, lake, and marsh that is tributary to Little Lake Butte des Morts. Neenah
Slough is impaired with degraded habitat and low dissolved oxygen due to TP. A small area on the
northern most tip of the City is tributary to Neenah Slough. This area is part of the Winnebago County
Fairgrounds on the northside of Sunnyview Road (CTH Y). The area draining to Neenah Slough is
open space or undeveloped area.
2.4 Land Use and Municipal Limits
2.4.1 General Background
The type and distribution of land use has a major impact on the hydrology and urban stormwater
pollution within a watershed. The volume and rate of stormwater runoff increases as the percentage
of impervious surfaces (streets, parking lots, roofs, etc.) in an area increases. In turn, the amount of
impervious surface is related to land use. As development occurs, the impervious area generally
increases significantly. Land use also plays an important role in determining the types and amounts
of pollutants that are carried by runoff.
Highly urbanized commercial and industrial areas generally contain a high percentage of impervious
area and generate high amounts of pollutants. These pollutants include sediment (TSS), nutrients
(TP), bacteria, metals, and toxic substances. Less intensive development, such as low to medium
density residential lands, contains a lower amount of impervious area and generates lower levels of
most pollutants.
2.4.2 Data Sources and Methods
To create the land use for the TMDL analysis, current (July 2020) parcel data was reviewed to
determine the designated land use by parcel. That land use designation was then compared to the
2014 Windows Source Loading and Management Model (WinSLAMM) land use designation and a
2018 aerial photograph of the City.
The entire study area includes approximately 17,890 ac. After removing the 2,545 ac of excluded
areas, as noted in Section 2.2, the resulting analyzed area for this study is approximately 15,345 ac,
as shown by land use in Table 2-3.
Table 2-3. TMDL Categorized WinSLAMM Land Use
WinSLAMM Land Use Area (ac) Area (% of total)
Commercial 2,558 16.6%
Airport 881 5.7%
Downtown 266 1.7%
Office Park 158 1.0%
Shopping Center 304 2.0%
Strip Commercial 949 6.2%
Industrial 1,956 12.7%
Light Industrial 1,487 9.7%
Medium Industrial 470 3.1%
Institutional 1,660 10.8%
Hospital 88 0.6%
City of Oshkosh Stormwater Quality Management Plan Section 2
2-5
Oshkosh SWMP Final
Table 2-3. TMDL Categorized WinSLAMM Land Use
WinSLAMM Land Use Area (ac) Area (% of total)
Institutional 1,121 7.3%
Schools 283 1.8%
UW Oshkosh 169 1.1%
Parks and Open Space 2,956 19.2%
Cemetery 204 1.3%
Open Space, Undeveloped 1,514 9.9%
Parks 1,093 7.1%
Railroad 145 0.9%
Residential 6,240 40.6%
Low Density Residential 718 4.7%
Medium Density Residential 3,282 21.4%
High Density Residential 1,276 8.3%
Multifamily Residential 917 6.0%
Mobile Home 46 0.3%
Totals 15,371 100.0%
The land use categories were selected to represent the best match to the definitions used by
WinSLAMM and WDNR criteria for modeling. Figure 2-3 in Appendix A shows the generalized
WinSLAMM land use categories for this study.
2.5 Precipitation
Precipitation data is another parameter that is used in WinSLAMM. When modeling stormwater
pollution loadings, cumulative runoff, and pollution loads from the more frequent “normal” rain
events (in the range of 0.25-inch to 1.5-inch rains) are more important than the pollution from the
less frequent “larger” rain events. This is because the more frequent events generate the majority of
the volume of urban stormwater runoff in any given year; therefore, modeling simulations are
performed with rainfall records for a representative time period.
Current guidance from the WDNR stipulates that rainfall records for a five-year period should be
used. Rainfall input files were developed by the USGS for several locations throughout the State of
Wisconsin, and the WDNR specifies that the file developed for a location closest to the project area
be used in the analysis. Thus, the Green Bay five-year rainfall file for rain events between 1968 and
1972 was used for the stormwater pollution modeling in Oshkosh.
2.6 Soils
Soil properties influence the volume and rate of runoff generated from rainfall events. Soils that
allow rainfall to freely drain into the ground (sandy soils) will result in lower runoff rates and volumes.
Soils that restrict the infiltration of rainfall into the ground (clayey soils) will cause higher runoff rates
and volumes. The United States Department of Agriculture (USDA) Natural Resource Conservation
Service (NRCS) classifies soils based on their runoff potential into Hydrologic Groups A, B, C, or D.
Soils in Hydrologic Group A have a high infiltration capacity and low runoff potential (generally sandy
City of Oshkosh Stormwater Quality Management Plan Section 2
2-6
Oshkosh SWMP Final
or gravelly soils). Group D soils have a low infiltration capacity and a high runoff potential (generally
soils with high clay content).
The soils characteristics are occasionally updated by the USDA/NRCS. For this plan, the soils data
was downloaded from the USDA/NRCS website in June 2020, and the soils files, dated September
24, 2012, were used. According to the NRCS Soil Survey, the project area consists of mostly Group C
soils. There is a mixture of the other soils found in the remaining areas of the City. NRCS Soil Survey
information shows that these soils exhibit a wide range of properties and infiltration ability. The
NRCS Soil Surveys were developed to summarize soil characteristics. Actual soil conditions for a
specific location can vary from the general (mapped) condition. Table 2-4 summarizes the extent of
soil hydrologic groups within the project area. Figure 2-4 in Appendix A displays the distribution of
NRCS hydrologic groups within the City.
Table 2-4. USDA/NRCS Soil Hydrologic Groups and WinSLAMM Designation for Project Area
Soil Hydrologic Group
(USDA/NRCS)
WinSLAMM Soil Texture
Designation Project Area Coverage (ac) Project Area Coverage
(% of Total)
A Sandy 13 0.1%
B Silty 7 0.0%
C or D Clayey 15,351 99.9%
Totals 15,371 100%
3-1
Oshkosh SWMP Final
Section 3
Stormwater Pollution Analysis
Urban stormwater pollution is made up of many contaminants including sediment, nutrients, metals,
organic compounds, and pathogens. Stormwater pollution can have significant negative impacts on
receiving waters. The assessment of stormwater pollution through a modeling approach is the core
of this Plan. The City has been issued, and is required to follow, a municipal stormwater discharge
permit (MS4 Permit) which regulates stormwater pollution from the City’s stormwater conveyance
system. As previously discussed in Section 1.1, the City already meets the NR 151.13 TSS control
requirements for TSS (see Section 4.2 and Section 4.3 of the 2014 Plan for more details).
This study describes the stormwater pollution conditions in the City of Oshkosh with a focus on TSS
and TP management in order to meet the Upper Fox/Wolf and Lower Fox TMDLs reduction targets for
the City (see Table 1-1).
3.1 Methodology
To analyze TMDL stormwater pollution loads for the City’s urban areas, a computer simulation
model, WinSLAMM, Version 10.4.1, was used. WinSLAMM was originally developed by the WDNR
and is now licensed by PV & Associates (see www.winslamm.com for more information). WinSLAMM
is the most commonly used model in Wisconsin to assess urban stormwater pollution loads and
SMP pollution reduction performance. The WDNR has established specific guidance for application
of the model to assess pollution management related to TMDL targets by MS4s.
The project area, as described in Section 2.2, was determined based on WDNR guidelines to meet
the compliance requirements of the Upper Fox/Wolf and Lower Fox TMDLs. In keeping with the
WDNR guidelines for conducting these analyses and defining the “no stormwater control measure”
or “no controls” condition, a variety of steps were conducted as described in the following
paragraphs.
A project geographical information system (GIS) database was created containing information
pertaining to stormwater pollution in the City. Information in the database includes:
• Soil Hydrologic Group and WinSLAMM soil texture designation
• Land use, as of approximately July 2020
• Street Drainage type (curb and gutter or grass swale)
• Stormwater Permitted entities within the municipal boundary (Winnebago County properties,
WisDOT right-of-ways, permitted Quarry area)
• Existing grass swales meeting WDNR requirements
• Existing street cleaning schedule
• Existing structural SMPs that are under the City’s jurisdiction
• The municipal boundary as of July 2020
WinSLAMM requires input files that describe characteristics of the soil, land cover, drainage system,
and precipitation, and other factors of the project area. The model uses a five-year rainfall record to
calculate runoff and pollution loads. As previously described, the 1968 to 1972 rainfall data for the
City of Green Bay was used for this application.
City of Oshkosh Stormwater Quality Management Plan Section 3
3-2
Oshkosh SWMP Final
WinSLAMM also requires support files. The United States Geological Survey (USGS) and WDNR
developed versions of these files for use in Wisconsin. The files are based on extensive field
monitoring and calibration. The latest versions of these WinSLAMM files were obtained from the
USGS and used for this project.
The files used are:
• WisReg –Green Bay Five Year Rainfall.ran (1968 – 1972)
• WI_GEO03.ppdx
• WI_SL06 Dec06.rsvx
• V10.1 WI_AVG01.pscx
• WI_Res and Other Urban Dec06.std
• WI_Com Inst Indust Dec06.std
• Freeway Dec06.std
WinSLAMM was run, and pollution loads were calculated for the applicable analyzed area of each
TMDL reachshed. The pollutants analyzed for this project were TSS and TP.
3.2 Results: “No Controls” Conditions
3.2.1 TMDL Reachshed Loads
To understand compliance with the Upper Fox/Wolf and Lower Fox TMDL pollution loading
reductions for TSS and TP for each reachshed within the City (see Section 1.2 and Table 1-1 of this
report), the pollution loads for each reachshed need to be calculated under a “no controls” condition.
This is a theoretical condition of the amount of annual pollutant loading that would come from the
City if there were no SMPs removing pollutants from stormwater runoff. The loadings are calculated
using the WinSLAMM model based on the various combinations of land uses and soils for drainage
areas in each reachshed that are included in the analysis. For the “no controls” condition, the entire
City is assumed to have curb and gutters because swales are considered to be a treatment practice.
The resulting “no controls” loads are listed in Table 3-1A.
Table 3-1A. “No Controls” Pollutant Loading Results
Reachshed Total Area (ac) TSS Load (tons/year) TP Load (lbs/year)
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 2,707 354 2,104
Lake Butte des Morts 2,137 242 1,392
Fox River – Lake Butte des Morts
to Lake Winnebago 3,452 557 3,023
Lake Winnebago 7,041 893 5,167
Totals 15,336 2,045 11,685
Lower Fox TMDL Reachshed
Neenah Slough 35 2.2 20
The total area analyzed in this study has increased by about 5 percent from the 2014 Plan. TSS and
TP “no controls” loads have increased by 3 percent and 2 percent, respectively, when compared to
City of Oshkosh Stormwater Quality Management Plan Section 3
3-3
Oshkosh SWMP Final
the 2014 Plan. The increases in pollutant loadings seem reasonable and relatively proportional to
the change in study area due to the expansion of the municipal limits and developed area in the City.
3.2.2 Non-City MS4 TMDL Reachshed Loads
The “no controls” loads from the other MS4s inside the City of Oshkosh municipal limits were also
calculated due to the pending status of agreements with these entities. These loads are summarized
in Table 3-1B. It should be noted that these loads are also included in the Citywide results provided
in Table 3-1A.
Table 3-1B. Other MS4s Within the City of Oshkosh Municipal Limits - “No Controls” Pollutant Loading Results
Reachshed Entity Total Area (ac) TSS Load (tons/year) TP Load (lbs/year)
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek Winnebago County
Highway 26.5 4.0 21.0
Lake Butte des Morts
Winnebago County
Highway 6.7 0.4 3.8
Winnebago County –
Large Parcels 553.3 31.7 238.4
Fox River – Lake Butte des
Morts to Lake Winnebago
UW-Oshkosh 168.9 28.8 167.7
Winnebago County
Highway 13.1 3.0 12.7
Winnebago County –
Large Parcels 19.8 4.2 17.0
Lake Winnebago
Winnebago County -
Airport 829.7 38.2 346.9
Winnebago County
Highway 14.4 2.7 12.4
Winnebago County –
Large Parcels 541.3 46.7 324.8
Lower Fox TMDL Reachshed
Neenah Slough Winnebago County –
Large Parcels 34.8 2.2 19.6
3.2.3 City MS4 Only TMDL Reachshed Loads
The “no controls” loads from just the City of Oshkosh MS4 and excluding other MS4s within the City
municipal limits were also calculated. These loads are summarized in Table 3-1C. As with Table
3-1B, it should be noted that these loads are also included in the Citywide results provided in Table
3-1A. Combining the loads from Tables 3-1B and 3-1C will result in the loads in Table 3-1A.
City of Oshkosh Stormwater Quality Management Plan Section 3
3-4
Oshkosh SWMP Final
Table 3-1C. “No Controls” Pollutant Loading Results
Excluding Other MS4s Within the City of Oshkosh Municipal Limits
Reachshed Total Area (ac) TSS Load (tons/year) TP Load (lbs/year)
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 2,681 350 2,083
Lake Butte des Morts 1,577 210 1,150
Fox River – Lake Butte des Morts
to Lake Winnebago 3,250 521 2,825
Lake Winnebago 5,655 805 4,483
Totals 13,162 1,886 10,541
3.3 Existing Management Conditions (“With Controls”) Analysis
Following completion of the “no controls” conditions analysis to identify the amount of TSS and
TP loads available within the applicable project limits, the City’s existing stormwater management
practices (SMPs), sometimes referred to as stormwater control measures (SCMs) were evaluated.
This evaluation is intended to compare how much progress the City has made towards achieving the
TMDL goals for each of the various reachsheds in the City.
These five SMP categories are presented in the following sections:
• Street cleaning
• Catch basins with sumps
• Grass swales
• Regional SMPs
• Non-regional SMPs
3.3.1 Street Cleaning
The City of Oshkosh, like other communities, has had a street cleaning program in place for many
years, primarily for the aesthetic benefits of having clean and safe streets. Over time, the program
has expanded from conventional street cleaners to include high efficiency street cleaners which do a
better job of removing the finer material that is more impactful to our water resources. Additionally,
the City transitioned to an enhanced street cleaning program, following the completion of the 2008
Citywide SWMP, and the City continues to use this approach.
The City’s street cleaning schedule and equipment was verified with City of Oshkosh staff as part of
this project. The City continues to maintain street cleaning efforts in two different zones:
(1) downtown zone and (2) other remaining areas of the City.
Table 3-2 contains information on the various street cleaning zones including: scheduled cleaning
frequency, equipment/sweeper type used and cleaning season. Table 3-3 contains information
regarding parking parameters used in the WinSLAMM modeling. Figure 3-1 in Appendix A displays
the street cleaning zones in the City as described in Table 3-2. Areas not shown on Figure 3-1 as part
of the two street cleaning zones do not receive benefit from the street cleaning program. These
areas include streets without curb and gutter and areas that drain directly to a waterway without
entering a street (riparian areas).
City of Oshkosh Stormwater Quality Management Plan Section 3
3-5
Oshkosh SWMP Final
Table 3-2. Street Cleaning Program Details
Zone Cleaning Frequency Equipment
Downtown Weekly during Cleaning Season1 High Efficiency
Remainder of City Weekly - 1st 6 Weeks of Season1
Bi-weekly – Remainder of Season1
80% High Efficiency & 20% Mechanical – 1st 6 Weeks
100% High Efficiency (Mechanical as back-up) –
Remainder of Season
1Cleaning Season commences after spring snow melt (typically March) and continues until first snowfall (typically
end of November.
The City utilizes a mix of high efficiency and mechanical street cleaners in the areas outside of the
downtown street cleaning zone. The mechanical cleaner is used regularly during the intense six-week
cleaning program, and then occasionally as a back-up through the remainder of the season. To
evaluate the performance of the street cleaning program it was assumed that in areas outside of the
downtown zone 80-percent of the cleaning is completed by high efficiency equipment and
20-percent by mechanical sweepers. This assumption is conservative, consistent with the approach
from the 2014 SWMP, and needed due to limitations in the WinSLAMM software. The impact of the
pollutant reductions based on this assumption are minimal.
Table 3-3. Parking Density and Controls
Land Use Parking Density Parking Controls
Central Business District, UW Oshkosh Campus Extensive Short Term With Parking Controls
Cemetery, Golf Course, Suburban Residential,
Office Park, Shopping Center None With Parking Controls
Residential (high, medium and low), Park,
Industrial (light and medium), Strip Commercial Light With Parking Controls
Applying the WinSLAMM model and the two zones of street cleaning, the impact of the City’s street
cleaning program to reduce TSS and TP loads on each reachshed are shown on Table 3-4.
Table 3-4. Street Cleaning Program Pollutant Load Reduction Results
Reachshed Total Treated
Area (ac)
TSS Load
Reduction
(tons/year)
TSS Reduction %
(compared to “no
controls” total load)
TP Load
Reduction
(lbs/year)
TP Reduction %
(compared to “no
controls” total load)
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 2,326 48 13% 174 8%
Lake Butte des Morts 549 12 5% 38 3%
Fox River – Lake Butte
des Morts to Lake
Winnebago
2,902 78 14% 268 9%
Lake Winnebago 4,266 90 10% 307 6%
Totals 10,043 228 785
Lower Fox TMDL Reachshed
Neenah Slough 0 0 0% 0 0%
City of Oshkosh Stormwater Quality Management Plan Section 3
3-6
Oshkosh SWMP Final
3.3.2 Catch Basins with Sumps
During road reconstruction projects, the City installs catch basins with sumps as part of the storm
sewer drainage system to help reduce stormwater pollution. For this study, the analysis of catch
basins conducted as part of the 2014 SWMP was updated. Catch basins installed prior to 2014 were
incorporated from the 2014 SWMP and included the number of catch basins and catch basin
drainage areas. The City of Oshkosh provided GIS data identifying the location of all catch basins
installed between 2014 and 2020. Drainage areas to the new catch basins were delineated. The
WinSLAMM model from the 2014 SWMP was expanded to incorporate the new catch basins. Since
2014, there were approximately 900 catch basins installed that treat 485 ac. This results in a total
of 2,608 catch basins within the City, treating 1,730 ac. The catch basin parameters were verified
and include the following:
• Catch basin surface area = 6 square feet
• Outlet pipe diameter = 12 inches
• Sump depth = 18 inches
• Annual cleaning
The catch basins were analyzed within WinSLAMM to determine the pollution control achieved. The
WinSLAMM model from the 2014 SWMP was updated to include additional areas treated by catch
basins. In this model, all areas that are treated by catch basins are composited together and an
average catch basin density is utilized. A summary of the model results is provided in Table 3-5.
Figure 3-2 displays the locations of areas treated by catch basins. It should be noted that the results
in Table 3-5 display the impact of catch basins only. Most of the area treated by catch basins is also
treated by street cleaning. The effects of street cleaning and catch basin treatment in-series, as
calculated within the WinSLAMM model, is accounted for in the overall reductions shown in
Tables 3-9A and 3-9B.
Table 3-5. Catch Basin Pollutant Load Reduction Results
Reachshed Total Treated
Area (ac)
TSS Load
Reduction
(tons/year)
TSS Reduction %
(compared to “no
controls” total load)
TP Load
Reduction
(lbs/year)
TP Reduction %
(compared to “no
controls” total load)
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 239 5 1.5% 27 1.3%
Lake Butte des Morts 60 2 0.6% 7 0.5%
Fox River – Lake Butte
des Morts to Lake
Winnebago
583 17 3.0% 75 2.5%
Lake Winnebago 849 23 2.5% 103 2.0%
Totals 1,730 46 212
Lower Fox TMDL Reachshed
Neenah Slough 0 0 0% 0 0%
City of Oshkosh Stormwater Quality Management Plan Section 3
3-7
Oshkosh SWMP Final
3.3.3 Grass Swales
The City maintains small portions of its stormwater conveyance system as grassed swales.
Additionally, the Wittman Airport maintains an extensive system of grass swales. These swales treat
stormwater through filtration and infiltration of runoff.
3.3.3.1 City Grass Swales
The 2014 SWMP included eleven areas containing grass swales that were identified as 01 through
10 for swales in the City right-of-way, and a separate category for the airport swales. These swales
were categorized by geographic area, geometry, and longitudinal slope. Each of the City swales were
evaluated following the WDNR’s “Process to Assess and Model Grass Swales” to develop field
infiltration rates based on double-ring infiltrometer testing. The results of that effort were confirmed
with WDNR Staff (Gus Glazer). Supporting documentation from the infiltration testing was provided in
Appendix C of the 2014 SWMP.
As part of this study, the prior swale areas were reviewed with updated data provided by the City. As
part of this review, it was identified that some of the swales within Grass Swale Groups 3, 4, and 6
were removed.
• Group 3: Snell Road, east of STH 76 was converted to an urban road section as part of a street
reconstruction project and swales in this area were removed.
• Group 4: Sunnyview Drive, east of STH 76 has curb and gutter, swales in this area were removed
from the analysis.
• Group 6: Swales along West 9th Avenue from Oakwood Road, west to the City limits were
removed as part of a road reconstruction project.
3.3.3.2 Wittman Airport Grass Swales
Within Wittman Airport, the primary drainage system is grass swales. The presence of these swales
was identified during the 2014 SWMP and the pollution reduction capabilities of the Wittman Airport
swales was estimated. The 2014 analysis estimated the swale performance based on the City
roadside swale infiltration rate testing. As part of the current analysis, on-site grass swale testing and
evaluation was conducted.
Summary of Methods
Prior to field infiltration testing, a review of aerial photography, topographic data, and soils data was
conducted. An initial estimate for the location and relative dimensions of swales was developed.
Three proposed field infiltration testing sites were selected based on geographic location and the
size of the swales. The locations of proposed testing sites were submitted to the WDNR for review
and the locations were approved.
Field testing was conducted on November 11, 2021. Testing was conducted in accordance with the
WDNR’s “Process to Assess and Model Grass Swales.” During the testing, field measurements were
completed for swale geometry and a site tour of the entire Airport property was conducted to verify
the locations of swales and assess the relative shape (wide vs narrow). Supporting documentation
from the field testing is included in Appendix D. Measured infiltration rates ranged from 3.8- to
4.9-inches per hour. An average static infiltration rate of 4.4 inches per hour was calculated.
Following the completion of the field testing, the initial swale estimates for location and geometry
were revised, and a WinSLAMM model representing the airport and grass swales was developed. To
develop the model, swales were grouped into two main categories, one for the wide flat swales
common near the runway areas and another for the roadside ditch swales along the perimeter and
adjacent to on-site roads. Typical geometry for both types of swales were developed based on the
City of Oshkosh Stormwater Quality Management Plan Section 3
3-8
Oshkosh SWMP Final
field measurements performed during infiltration testing and City GIS data. Drainage areas to each
type of swale were delineated and used to develop a composite WinSLAMM model representing the
entire site. The composite WinSLAMM model includes the two separate swale types and the drainage
areas to each of the systems. The average static infiltration rate from the three tests performed in
the airport property was converted to a dynamic infiltration rate of 2.2 inches per hour and used for
both types of swales.
3.3.3.3 Grass Swales Results Summary
Analyzing the water quality treatment benefits provided by grassed swale areas is not done in the
same manner as some other SMPs where loads are based on application through treatment using
scaled standard land use files. The nature of swales requires that individual models be developed for
the swale treatment areas—much like individual models are developed for regional wet detention
ponds—to accurately predict treatment efficiencies. Furthermore, for areas where grassed swales are
tributary to a regional wet detention facility, the swales are modeled with the wet detention pond in
series to provide the most accurate representation of the combined treatment practices. Based on
this analysis, a total of 1,438 ac in the City are treated by swales as shown in Table 3-6 which
identifies the TSS and TP reductions for each swale area, by reachshed. Only reachsheds that have
analyzed swales are shown in the table. Figure 3-3 in Appendix A shows the locations of areas
treated by grass swales.
Table 3-6. City Grass Swale Pollutant Load Reduction Results
Reachshed Swale ID(s) in
Reachshed
Total Treated
Area (ac)
TSS Load
Reduction
(tons/year)
TSS Reduction %
(compared to “no
controls” total
load)
TP Load
Reduction
(lbs/year)
TP Reduction %
(compared to “no
controls” total load)
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 05, 06, 07, 08 45 6 1.7% 35 1.7%
Lake Butte des
Morts
01, 02, 03, 04, 05,
06 231 30 12.3% 145 10.5%
Fox River – Lake
Butte des Morts to
Lake Winnebago
07, 08 46 6 1.1% 25 0.8%
Lake Winnebago
02, 03, 04, 06, 08,
09, 10 490 62 7.2% 348 7.1%
Airport 626 27 93.1% 241 91.8%
Totals 1,438 104 795
Lower Fox TMDL Reachshed
Neenah Slough None 0 0 0% 0 0%
3.3.4 Regional SMPs
Regional wet detention basin SMPs that have been designed and constructed to treat stormwater
from developed (and developing) areas are a major part of improving stormwater quality in the City of
Oshkosh. Additionally, the City has two stormwater lift stations with sumps that serve as regional
SMPs. Within the City, regional SMPs are defined as City-owned practices designed to treat multiple
developments/parcels. Other practices treating a single parcel, or multiple parcels that are part of a
City of Oshkosh Stormwater Quality Management Plan Section 3
3-9
Oshkosh SWMP Final
common plan of development, such as a subdivision or industrial park, are considered non-regional
SMPs and are included in Section 3.3.6 below. The 2014 SWMP identified eight regional wet
detention basins and two stormwater lift stations that were in place at the time. Since 2014, one of
the regional wet detention basins (Mercy Hospital North) was reclassified as a non-regional SMP
based on additional information and an additional three regional wet detention basins have been
constructed by the City, resulting in a total of 12 regional SMPs that are included as part of this
study. The three new regional SMPs are identified as:
• 9th & Washburn Area Wet Detention Basin,
• Fernau Watershed – North Main Street Area Wet Detention Basin, and
• Libbey-Nicolet Watershed – North Main Street Area Wet Detention Basin.
Pertinent information (WinSLAMM model and detention basin tributary area) for each of these wet
detention basins was obtained from the City. The WinSLAMM models were executed in WinSLAMM
(version 10.4) for each facility. The TSS and TP reductions reported by the models were used for this
study. Details of regional facilities can be found in Table E-1 in Appendix E. This table lists the facility
ID, name, ownership (public or private), and TSS and TP removal efficiencies by reachshed. Table 3-7
lists TSS and TP removals associated with regional SMPs by TMDL reachshed. The locations of the
regional SMPs and their drainage areas are displayed on Figure 3-4 in Appendix A.
Table 3-7. Regional SMP Pollutant Load Reduction Results
Reachshed Total Treated
Area (ac)
Percent of Total
Reachshed
Area
TSS Load
Reduction
(tons/year)
TSS Reduction %
(compared to “no
controls” total
load)
TP Load
Reduction
(lbs/year)
TP Reduction %
(compared to “no
controls” total load)
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 423 16% 46 13.0% 203 9.7%
Lake Butte des Morts 0 0% 0 0.0% 0 0.0%
Fox River – Lake
Butte des Morts to
Lake Winnebago
1,184 34% 154 27.7% 644 21.3%
Lake Winnebago 868 12% 92 10.3% 358 6.9%
Totals 2,475 292 1,205
Lower Fox TMDL Reachshed
Neenah Slough 0 0% 0 0% 0 0%
3.3.5 Non-Regional SMPs
As described in Section 3.3.4, practices treating a single parcel, or multiple parcels that are part of a
common plan of development, such as a subdivision or industrial park, are considered non-regional
SMPs. Non-regional SMPs include biofilters, hydrodynamic separation devices (HSDs), catch basins,
small water quality ponds, and filtering devices. SMP treatment areas can range from less than an
acre to multiple acres. Non-regional SMPs are typically private; however, some SMPs, are public. The
2014 SWMP identified 50 non-regional SMPs as noted in Table 4-6 of that report. The information
for the non-regional SMPs in the 2014 SWMP (drainage area, pollution reduction percentages) were
generally utilized for this study unless a known change in condition warranted a different approach.
City of Oshkosh Stormwater Quality Management Plan Section 3
3-10
Oshkosh SWMP Final
Recent development and construction projects were reviewed by the City to identify non-regional
SMPs installed since 2014. A total of 116 new, non-regional, SMPs were identified. For these SMPs
the City provided WinSLAMM input/output data (PDFs) along with the parcel number(s) treated by
the SMPs, and the tributary area for the SMP. Additionally, the City researched operation and
maintenance (O&M) agreements for SMPs and provided information to the City.
Each of the non-regional SMPs (prior identified and new SMPs) were reviewed and categorized for
the purposes of inclusion into this study. The following process was utilized.
1. A GIS shapefile was developed to identify the spatial location of each SMP (note this file includes
regional SMPs described previously and non-regional SMPs). Pertinent data attributes including
SMP name and SMP type (wet detention basin, grass swale, biofilter, etc.) were also added to
this file.
2. The ownership of the SMP was classified as city-owned, privately owned, or owned by another
public entity, such as Winnebago County or UW-Oshkosh.
3. The status of an O&M agreement for the site was identified and classified into one of four
categories.
a. In Place: A recorded O&M agreement is on-file with the City.
b. In Progress: An O&M agreement is actively being worked on by the City and the owner. The
status of the agreement is being tracked in the City’s Evolve site plan review software and a
condition of final approval for the site is to have a signed O&M agreement in place.
c. Not Found: An O&M agreement could not be found as part of the City’s research for this
project. An agreement may exist, and the City is continuing to research existing practices
and the status of O&M for these sites as part of their MS4 program. For the purposes of this
study, sites in this category were excluded from the “with controls” analysis.
There were 86 sites where an O&M agreement could not be found. These sites are further
discussed in Section 4.1.1.
d. N/A: For sites owned by the City of Oshkosh a O&M agreement is not needed as they are the
responsible authority.
4. Pertinent site data provided by the City was reviewed and verified.
a. WinSLAMM model information generally included a PDF of model input/output. An exception
to this was city-owned non-regional SMPs where WinSLAMM mdb files were available. The
TSS and TP reduction achieved by each site was identified and assigned to the site. If TP
loads and reductions were not available as part of the original project file, typical rules of
thumb to estimate TP reductions based on TSS reductions were employed.
b. The treatment site and tributary area was also compared to the site development parcel(s)
and, if necessary, the percentage reduction for TSS and TP loadings were reduced on a total
area basis to not overestimate pollutant reductions for the site. The adjustment in treatment
reduction for the development was applied in lieu of creating individual SMP treatment
(tributary) areas and breaking up individual parcels due to the inefficiency of this exercise.
City of Oshkosh Stormwater Quality Management Plan Section 3
3-11
Oshkosh SWMP Final
As part of the data review portion of this plan development, Brown and Caldwell (BC) identified
23 additional locations where non-regional SMPs were observed, but data was not previously
provided and these sites were not included in the 2014 SWMP. These practices were generally wet
detention ponds that could be observed on aerial photography. Through further investigation it was
determined that these sites generally treated areas of new-development from between 2004 and
the 2014 SWMP. These sites were excluded from the 2014 SWMP, likely because areas developed
after 2004 are excluded from the NR 151 developed urban area standard (20 percent TSS reduction
requirement). The scope of work for this Study (and the grant associated with the project) included
effort to incorporate non-regional SMPs from sites developed after 2014. Additionally, data for sites
from this time period is more difficult to obtain because the City’s records for these sites are often
not digital. Also, current City workload did not allow for obtaining additional data for inclusion of
these sites into this plan. The sites that were identified are further discussed in Section 4.1.2. As a
future action, the City may further research these sites and incorporate the SMPs into the Citywide
SWMP to include the pollutant reduction they achieve.
Non-Regional SMP Summary
A total of 71 non-regional SMPs are incorporated into the “with controls” analysis. Table E-2 in
Appendix E contains details regarding the non-regional SMPs. This table lists the facility ID, name,
ownership (public or private), TSS and TP removal efficiencies, and O&M agreement status by
reachshed. The TSS and TP removals from non-regional SMPs are summarized by TMDL reachshed
in Table 3-8. The locations of the non-regional SMPs are shown on Figure 3-5 in Appendix A.
Table 3-8. Non-Regional SMP Pollutant Loading Results
Reachshed
Total
Treated
Area (ac)
TSS Load
Reduction
(tons/year)
TSS Reduction %
(compared to “no
controls” total load)
TP Load
Reduction
(lbs/year)
TP Reduction %
(compared to “no
controls” total load)
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 147 8 2.2% 39 1.9%
Lake Butte des Morts 438 18 7.5% 83 6.0%
Fox River – Lake Butte des
Morts to Lake Winnebago 92 5 0.9% 16 0.5%
Lake Winnebago 364 28 3.2% 90 1.7%
Totals 1,041 59 228
Lower Fox TMDL Reachshed
Neenah Slough 0 0 0.0% 0 0.0%
3.3.6 Results: “With Controls” Analysis
Following the individual analyses for street cleaning, catch basins, grass swales, regional SMPs, and
non-regional SMPs as presented in previous sections of this report, the treatment practices were
combined to evaluate their current collective impact on improving water quality. The most effective
practice was applied to each land area to avoid double counting where multiple practices treat the
same drainage area. The one exception to this is areas where street cleaning and catch basins are
both utilized. In these areas, WinSLAMM models were developed for the street cleaning and catch
basins operating in series. These practices function in tandem as they are both focused on street
areas. The street cleaning/catch basin models were used to determine the effect of those practices
in-series and these results were included in this analysis. Reachshed totals are therefore not equal
City of Oshkosh Stormwater Quality Management Plan Section 3
3-12
Oshkosh SWMP Final
to the sum of the individual treatment practices presented in prior tables. The results are shown,
sorted by reachshed and TMDL study area for TSS and TP in Table 3-9A and Table 3-9B, respectively.
The results of the analysis indicates that the City has met the TMDL TSS reduction targets for three
of the four Upper Fox/Wolf TMDL reachsheds. The target for Sawyer Creek is not met. Also, the TSS
reduction target for the Neenah Slough Reachshed in the Lower Fox River TMDL is not met.
The results also indicate that the City has not met the TMDL TP reduction targets for any of the five
TMDL reachsheds. As noted previously, the TP reduction targets are very challenging and will require
treatment of both dissolved and particulate forms of phosphorus. Current SMPs in Oshkosh primarily
address particulate phosphorus.
The Citywide “with controls” TSS and TP reductions of 31.4-percent and 24.2-percent, respectively,
represent an improvement of approximately, 2 percent from the 2014 SWMP. The 2014 SWMP only
considered TSS and TP reductions on a Citywide basis as TMDL reachsheds were not available in
2014. Thus, the reductions on a reachshed basis cannot be compared to the past plan. It should
also be noted that there are a number of non-regional SMPs that were included in the 2014 SWMP
which are not included in the current plan due to the uncertainty surrounding whether O&M
agreements are in place.
Graphically, the stormwater pollution control in the City is summarized on Figure 3-6 (“No Controls”
Total TP Load by Watershed), Figure 3-7 (“With Controls” Total TP Load by Watershed), Figure 3-8
(“No Controls” Unit TP Load by Watershed) and Figure 3-9 (With Controls Unit TP Load by
Watershed). These figures show the total TP loading and unit TP loading on a watershed basis in
both the “no controls” and “with controls” conditions. The “no controls” figure can be compared to
the “with controls” figure of the corresponding map to identify the benefit of the existing SMPs.
Additionally, the figures can be used to identify areas that generate large TP loads, and/or a high unit
load for targeting the location of future SMPs. Further, tabular results on a watershed basis are
included in Table E-3 in Appendix E.
Table 3-9A. “With Controls” TSS Reduction Results
Reachshed Total Area
(ac)
“No
Controls”
TSS Load
(tons/year)
“With Controls”
TSS Load
Reduction
(tons/year)
TMDL Target
TSS Load
Reduction %
“With Controls”
TSS Reduction %
(compared to
“no controls”
total load)
Is TSS Load
Reduction
Target Met?
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 2,707 354 98 58.4% 27.8% No
Lake Butte des Morts 2,137 242 56 20% 23.2% Yes
Fox River – Lake Butte des
Morts to Lake Winnebago 3,452 557 213 20% 38.3% Yes
Lake Winnebago 7,041 893 275 20% 30.8% Yes
Totals 15,336 2,045 643 31.4%
Lower Fox TMDL Reachshed
Neenah Slough 35 2 0 52% 0% No
City of Oshkosh Stormwater Quality Management Plan Section 3
3-13
Oshkosh SWMP Final
Table 3-9B. “With Controls” TP Reduction Results
Reachshed Total Area
(ac)
“No
Controls”
TP Load
(lbs/year)
“With Controls”
TP Load
Reduction
(lbs/year)
TMDL Target
TP Load
Reduction %
“With Controls”
TP Reduction %
(compared to
“no controls”
total load)
Is TP Load
Reduction
Target Met?
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 2,707 2,104 425 85.6% 20.2% No
Lake Butte des Morts 2,137 1,392 255 85.6% 18.3% No
Fox River – Lake Butte
des Morts to Lake
Winnebago
3,452 3,023 865 85.6% 28.6% No
Lake Winnebago 7,041 5,167 1,282 85.6% 24.8% No
Totals 15,336 11,685 2,827 24.2%
Lower Fox TMDL Reachshed
Neenah Slough 35 20 0 40.5% 0.0% No
3.3.7 Non-City MS4 TMDL Reachshed With Control Loads
The “with controls” loads from the other MS4s inside the City of Oshkosh municipal limits were also
calculated due to the pending status of agreements with these entities. These loads are summarized
in Tables 3-10A and 3-10B for TSS and TP, respectively. As previously noted in the “no controls”
section, these loads are also included in the Citywide results provided in Table 3-9A and Table 3-9B.
Table 3-10A. Other MS4s Within the City of Oshkosh Municipal Limits – “With Controls” TSS Reduction Results
Reachshed Entity Total Area
(ac)
“No Controls”
TSS Load
(tons/year)
“With Controls” TSS
Load (tons/year)
“With Controls” TSS
Reduction %
(compared to “no
controls” total load)
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek Winnebago County Highway 26 4 3 25.0%
Lake Butte des Morts
Winnebago County Highway 7 0 0 4.8%
Winnebago County – Large
Parcels 553 32 25 21.0%
Fox River – Lake Butte
des Morts to Lake
Winnebago
UW-Oshkosh 169 29 25 13.0%
Winnebago County Highway 13 3 1 73.2%
Winnebago County – Large
Parcels 20 4 2 46.1%
Lake Winnebago
Winnebago County - Airport 830 38 12 68.6%
Winnebago County Highway 14 3 2 15.5%
Winnebago County – Large
Parcels 541 47 39 15.6%
Lower Fox TMDL Reachshed
Neenah Slough Winnebago County – Large
Parcels 35 2 2 0.0%
City of Oshkosh Stormwater Quality Management Plan Section 3
3-14
Oshkosh SWMP Final
Table 3-10B. Other MS4s Within the City of Oshkosh Municipal Limits – “With Controls” TP Reduction Results
Reachshed Entity Total Area
(ac)
“No Controls” TP
Load (lbs/year)
“With Controls” TP
Load (lbs/year)
“With Controls” TP
Reduction %
(compared to “no
controls” total load)
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek Winnebago County Highway 26 21 18 16.8%
Lake Butte des Morts
Winnebago County Highway 7 4 4 2.5%
Winnebago County – Large
Parcels 553 238 193 19.2%
Fox River – Lake Butte
des Morts to Lake
Winnebago
UW-Oshkosh 169 168 155 7.5%
Winnebago County Highway 13 13 4 65.7%
Winnebago County – Large
Parcels 20 17 11 36.9%
Lake Winnebago
Winnebago County - Airport 830 347 109 68.6%
Winnebago County Highway 14 12 11 10.4%
Winnebago County – Large
Parcels 541 325 289 10.9%
Lower Fox TMDL Reachshed
Neenah Slough Winnebago County – Large
Parcels 35 20 20 0.0%
3.3.8 City MS4 Only TMDL Reachshed With Control Loads
The “with controls” loads from just the City of Oshkosh MS4 that excludes other MS4s within the City
municipal limits were also calculated. These loads are summarized in Tables 3-11A and 3-11B. It
should be noted that as with Tables 3-10A and 3-10B, these loads are also included in the Citywide
results provided in Tables 3-9A and 3-9B. Combining the loads from Tables 3-10A and 3-10B and 3-
11A and 3-11B will produce in the results in Tables 3-9A and 3-9B.
City of Oshkosh Stormwater Quality Management Plan Section 3
3-15
Oshkosh SWMP Final
Table 3-11A. “With Controls” TSS Reduction Results
Excluding Other MS4s Within the City of Oshkosh Municipal Limits
Reachshed Total Area
(ac)
“No
Controls”
TSS Load
(tons/year)
“With Controls”
TSS Load
Reduction
(tons/year)
TMDL Target
TSS Load
Reduction %
“With Controls”
TSS Reduction %
(compared to
“no controls”
total load)
Is TSS Load
Reduction
Target Met?
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 2,681 349.8 97.3 58.4% 27.8% No
Lake Butte des Morts 1,577 210.0 49.5 20% 23.5% Yes
Fox River – Lake Butte des
Morts to Lake Winnebago 3,250 520.7 205.2 20% 39.4% Yes
Lake Winnebago 5,655 805.1 241.1 20% 30.0% Yes
Totals 13,162 1,886 593.1 31.5%
Table 3-11B. “With Controls” TP Reduction Results
Excluding Other MS4s Within the City of Oshkosh Municipal Limits
Reachshed Total Area
(ac)
“No
Controls”
TP Load
(lbs/year)
“With Controls”
TP Load
Reduction
(lbs/year)
TMDL Target
TP Load
Reduction %
“With Controls”
TP Reduction %
(compared to
“no controls”
total load)
Is TP Load
Reduction
Target Met?
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 2,681 2,083 421 85.6% 20.2% No
Lake Butte des Morts 1,577 1,150 209 85.6% 18.2% No
Fox River – Lake Butte
des Morts to Lake
Winnebago
3,250 2,825 838 85.6% 29.7% No
Lake Winnebago 5,655 4,483 1,008 85.6% 22.5% No
Totals 13,162 10,541 2,476 23.5%
4-1
Oshkosh SWMP Final
Section 4
Alternative Stormwater
Management Practices Evaluation
The “with controls” analysis, documented in Section 3 of this report, indicated that the City’s
stormwater management program meets TSS goals in 3 of 5 reachsheds, however it does not meet
the TP goals in any of the reachsheds. To help the City understand potential avenues for
implementation of additional stormwater management practices, eight different practices or
approaches towards compliance are discussed in this study, and presented in the following sections.
4.1 Incorporation of Additional Existing Non-Regional SMPs
As described in Section 3.3.5, there are numerous non-regional SMPs located across the City. A
review of data and attributes of those SMPs identified that there was missing information and/or the
lack of operation and maintenance agreements for several of them. Generally speaking, these SMPs
are privately owned and were required by the City’s Municipal Code. These SMPs could be
incorporated into the City’s TMDL compliance plan, along with the other non-regional SMPs included
as identified in the “with controls” analysis, if the information gaps can be filled. The non-regional
SMPs can be categorized into two groups as described in the following sections.
4.1.1 SMPs with O&M Agreements Not Found
As part of the data collection for non-regional SMPs, the City researched O&M agreements for non-
City owned (private) SMPs. During this research, there were 87 SMPs where an O&M agreement
could not be located, but had the necessary information regarding the pollution control provided by
these sites, such as WinSLAMM input/output data (generally PDF files) and the area treated by the
SMP. The breakdown of sites and the area associated with them is listed in Table 4-1.
The estimated pollution control associated with these sites was calculated in a manner consistent
with the process outlined in Section 3.3.5. Table F-1 in Appendix F contains details regarding the
non-regional SMPs where O&M agreements could not be located. The potential additional TSS and
TP removals from these SMPs are summarized by TMDL reachshed in Tables 4-2A and 4-2B,
respectively. The locations of these SMPs are shown on Figure 4-1 in Appendix A.
Table 4-1. Additional Non-Regional SMPs with O&M Agreements Not Found Summary
Reachshed # of SMPs Area Treated (acres)
Sawyer Creek 14 256
Lake Butte des Morts 11 334
Fox River – Lake Butte des Morts to Lake
Winnebago 29 208
Lake Winnebago 33 730
City of Oshkosh Stormwater Quality Management Plan Section 4
4-2
Oshkosh SWMP Final
Table 4-2A. Additional Non-Regional SMPs with O&M Agreements Not Found Potential TSS Reduction Results
Reachshed
TMDL
Target
TSS Load
Reduction
%
Existing TSS
Reduction %
(compared to
“no controls”
total load)
Potential
Increased
TSS Load
Reduction
(tons/year)
Potential Increased
TSS Reduction %
(compared to “no
controls” total load)
Potential Total
TSS Reduction %
(compared to
“no controls”
total load)
Is TSS
Load
Reduction
Target
Met?
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 58.4% 27.8% 23 6.4% 34.1% No
Lake Butte des Morts 20% 23.0% 16 6.6% 29.8% Yes
Fox River – Lake Butte
des Morts to Lake
Winnebago
20% 38.3% 3 0.5% 38.8% Yes
Lake Winnebago 20% 30.8% 48 5.3% 36.1% Yes
Totals 31.6% 89 4.2% 35.8%
Lower Fox TMDL Reachshed
Neenah Slough 52% 0% 0 0% 0% No
Table 4-2B. Additional Non-Regional SMPs with O&M Agreements Not Found Potential TP Reduction Results
Reachshed
TMDL
Target TP
Load
Reduction
%
Existing TP
Reduction %
(compared to
“no controls”
total load)
Potential
Increased TP
Load
Reduction
(lbs/year)
Potential Increased
TP Reduction %
(compared to “no
controls” total load)
Potential Total
TP Reduction %
(compared to
“no controls”
total load)
Is TP Load
Reduction
Target
Met?
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 85.6% 20.2% 102 4.8% 25.0% No
Lake Butte des Morts 85.6% 18.3% 58 4.2% 22.5% No
Fox River – Lake Butte des
Morts to Lake Winnebago 85.6% 28.6% 9 0.3% 28.9% No
Lake Winnebago 85.6% 24.8% 199 3.9% 28.7% No
Totals 24.3% 367 3.0% 27.3%
Lower Fox TMDL Reachshed
Neenah Slough 40.5% 0.0% 0 0% 0% No
It should be noted that some of the additional non-regional SMPs where O&M agreements were not
found are located upstream of regional SMPs or grass swales. The incorporation of these sites does
not increase the overall pollutant reductions in the City and this is reflected in Table F-1. Priority to
identify, and/or obtain, additional O&M agreements should be given to sites that are in areas that do
not otherwise receive treatment by regional practices or grass swales.
4.1.2 Previously Unidentified Non-Regional SMPs
Through the course of the data review process, there were also 39 locations where an SMP was
observed on aerial photography, but was not identified in the 2014 SWMP, or within the data
provided by the City for recently implemented non-regional SMPs. It is believed these SMPs were
constructed as part of new developments after 2004, but prior to 2014. See section 3.3.5 for
additional information. Furthermore, there are likely additional SMPs that could not be observed via
City of Oshkosh Stormwater Quality Management Plan Section 4
4-3
Oshkosh SWMP Final
aerial photography that also exist. To account for these sites towards TMDL compliance, additional
research is needed to identify the pollution control they achieve and whether an O&M agreement
exists.
Figure 4-2 in Appendix A provides the location of the SMPs identified where data is not available. An
estimate of the pollution control associated with these sites could not be made due to lack of
information. As with the SMPs with O&M agreements not found, some of these sites are located
upstream of regional SMPs or grass swales. Again, priority should be given to further research sites
that were identified outside of areas that receive treatment by a regional practice or grass swale.
Three particular SMPs that fall into this category are the east, middle, and west ponds in the
Southwest Industrial Park. These are known ponds within the City, however, data does not exist
(WinSLAMM model or approved SWMP) to document the pollution removal efficiency of the ponds.
To incorporate these ponds into the analysis, WinSLAMM models will need to be developed to
identify the pollution control achieved.
4.2 Street Cleaning
The City of Oshkosh conducts a street cleaning program as presented in Section 3.3.1. The City’s
street cleaning program was evaluated in detail as part of the 2008 Citywide SWMP. As a result of
the analysis from the 2008 Citywide SWMP the current program was implemented, and the program
was determined to be optimized. No further analysis of the program was completed as part of this
study.
It should be noted that street cleaning is a component of the City’s leaf management program. The
leaf management program was also evaluated as part of this plan and is discussed in detail in
Section 4.3.
4.3 Leaf Management
The City of Oshkosh operates a bulk leaf collection program every fall. The program consists of
collecting leaves piled by residents on the street terrace. Following the collection of the leaves, the
City also conducts street cleaning to collect remaining leaf debris. One benefit of this program is that
it reduces phosphorus discharges to downstream waterbodies. In recent years, research regarding
the phosphorus reduction benefits of leaf management programs has been conducted by the WDNR,
USGS, and other partners. As a result, the WDNR has developed guidance (Municipal Phosphorus
Reduction Credit for Leaf Management Programs, February 2, 2022) to provide criteria for numeric
phosphorus reduction credit for leaf collection programs that can be applied by municipalities
towards compliance with TMDLs. A copy of the guidance document is included in Appendix G.
4.3.1 Eligible Areas for Numeric Credit from Leaf Management
Under WDNR guidance, there are conditions that define the area that is eligible for leaf management
credit. To be eligible, the area must have a residential land use, curb and gutter streets, a high level
of tree canopy, and not be treated by a downstream structural SMP (such as a pond). Table 4-3
summarizes the area eligible for leaf management credits. The location of the areas eligible for the
leaf management credit are shown on Figure 4-3.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-4
Oshkosh SWMP Final
Table 4-3. Area Eligible for Leaf Management Credit
Criteria Eligible Area
Land use is residential 6,231 acres
Above criteria and curb & gutter street section 5,983 acres
Above criteria and high level of tree canopy 23 acres
Above criteria and not treated by a structural SMP 17 acres
To determine whether there is a high level of tree canopy, there are two options provided by the
WDNR as follows:
• Option A: An average of one or more medium to large canopy trees located between the sidewalk
and the curb for every 80 linear feet of curb.
• Option B: An average of 40 percent or greater leaf canopy over the pavement, or 45 percent tree
canopy or greater over the right-of-way determined using leaf-on aerial photography.
The analysis was conducted using Option A, utilizing the City of Oshkosh GIS tree dataset. This
dataset represents trees within City property which includes the right-of-way and parks. The dataset
includes various attributes regarding trees, including the tree diameter at breast height. It was
assumed that a diameter at breast height of 6-inches or greater equated to a medium to large
canopy. In conjunction with the tree data, the City’s street centerline GIS file was utilized. The street
centerline file was clipped to areas meeting the land use and street section criteria. The number of
medium or large trees along each segment (intersection to intersection) was then counted. The
length of the street segment was then multiplied by two to account for curb and gutter on both sides
of the street. This length was divided by the count of trees along each segment to calculate the
average medium or large tree spacing. If the tree spacing was less than 80-feet the segment was
identified as eligible.
The amount of land eligible for leaf management credit is a small percentage of the overall
residential area within the City. Initial expectations were that a much larger area of the City would be
eligible. The underlying data, analysis process, and alternative data sources were considered to
further review whether the procedures utilized were reasonable and appropriate. The following items
were considered:
1. The City’s tree dataset was reviewed in further detail. Figure 4-4 shows the location of trees
within the City’s dataset categorized by the tree size. In total, the City’s dataset has
approximately 10,800 trees, of which 73-percent are less than 6-inches in diameter at breast
height.
2. Google street view was utilized to spot check residential areas throughout the City. It was
generally observed that the images in street view correlated with the tree dataset. There were
many areas where no trees in the terrace are observed. In other areas, the trees were generally
small and appeared to be installed as part of recent street reconstruction projects. Other areas
showed occasional large tree canopy; however, they were typically isolated with a small number
of trees on a single block, and would not equate to a medium level of tree canopy.
3. A portion of the leaf management studies conducted by the USGS occurred in the City of
Oshkosh. The data associated with the study area was reviewed to determine if it conflicted with
the analysis conducted as part of this study. The USGS study did not show significant TP
reduction (less than 15 percent TP reduction) from the leaf management operations in the study
area. Additionally, the tree canopy in the study area was lower than the 40-percent high canopy
threshold identified by the WDNR.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-5
Oshkosh SWMP Final
4. The WDNR community tree canopy mapping application
(https://dnr.wisconsin.gov/topic/urbanforests/ufia/plan-treecanopy) was reviewed. This
mapping data showed a city-wide tree canopy of 9.2 percent across the entire City. The data
could be further reviewed at a detailed level. At the “Block” level, the tree canopy was up to
53 percent within residential areas of the City. However, the 53 percent appears to be an outlier
and lower values of a 20- to 30-percent tree canopy was generally seen. Additionally, this data
includes the entire tree canopy, both within the right-of-way and over private parcels. Looking at
the detailed level of tree canopy did not show significant areas with a medium/high level of
canopy over the streets.
Based on the review of the various additional datasets, it was believed that, in fact, there are likely
relatively few areas of the City that currently qualify for leaf management credit. It should be noted
that the leaf management credit criteria may be revised in the future as additional data becomes
available. Also, trees continue to grow, and the City’s tree planting program may mature and result in
additional areas with significant levels of tree canopy. This topic can be revisited as tree growth
occurs, additional information becomes available, and/or if WDNR policy changes.
4.3.2 Existing Leaf Management Program and WDNR Guidance Criteria
In addition to the criteria regarding areas that are eligible for leaf management credit, the WDNR
guidance document established leaf management programmatic criteria. The following section
describes the requirements of the WDNR guidance document and how the City’s program compares:
1. WDNR Criteria #1: The municipality has an ordinance prohibiting residents from placement of
leaves in the street.
a. The City’s Municipal Code Chapter 14 (Storm Water Management) and Chapter 25 (Streets
and Sidewalk) have provisions that prohibit the placement of leaves in the street.
2. WDNR Criteria #2: The municipality has a policy that leaves are placed by residents on the street
terrace, and collected at a specified frequency and timing. As part of the collection, the leaves
are collected by loading them into an enclosed vehicle without being left in the street overnight.
a. The City’s “2022 Curbside Brush & Loose Leaf Collection Guidelines” (included in Appendix
G) describes the City’s policies related to the placement of leaves in the terrace and
specifically identifies that they should not be placed in the street or gutter. The policy also
identifies leaf collection dates for areas of the City that correlate to the City’s garbage
collection schedule.
3. WDNR Criteria #3: If on street parking densities are greater than “light”, there is an ordinance or
enforceable policy to restrict parking during leaf collection and street cleaning.
a. Within residential areas of the City, the parking densities are light.
4. WDNR Criteria #4: The leaf collection program starts no later than October 1 each year. It should
be noted that the guidance document identifies that the exact timing of leaf fall varies each year.
The guidance document should be consulted for further information regarding when street
cleaning and bulk collection activities associated with street cleaning begins.
a. The “2022 Curbside Brush & Loose Leaf Collections Guidelines” identify a start date of
October 17 for the leaf collection program.
b. To comply with the WDNR guidance, the City would potentially need to modify their program
to comply with the start date of the guidance. Experience of City staff indicates that leaf fall
does not occur at a high enough rate to trigger the start of the program until mid-October.
Based on the WDNR guidance, the leaf accumulation conditions in the street will need to be
monitored, and collection and street cleaning activities may need to begin earlier.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-6
Oshkosh SWMP Final
5. WDNR Criteria #5: The leaf collection program occurs three to four times throughout October
and November.
a. The City’s program occurs five times on a weekly basis between mid-October and mid-
November as per the “2022 Curbside Brush & Loose Leaf Collection Guidelines”.
b. It is believed that the City complies with this criteria as the adequate number of collection
cycles is completed. It is possible that the City’s program may need to be extended to the
end of November to meet the requirements. The WDNR should be consulted to verify how
long collection activities should occur.
With meeting the criteria above, there are two levels of TP reduction that can be achieved by leaf
management activities under the current guidance document. These levels are described below.
1. Numeric Credit Option #1: Within 24-hours of leaf collection the streets within the collection area
are cleaned with either a mechanical or high-efficiency street cleaner. A 17 percent TP reduction
credit is achieved under this option.
2. Numeric Credit Option #2: Weekly street cleaning occurs with high efficiency street cleaners in
addition to the loose leaf collection. A 25 percent TP reduction credit is achieved under this
option.
The City’s street cleaning program fully meets numeric credit option #1 currently. In addition, weekly
street cleaning occurs in the downtown zone of the City. Furthermore, it is believed that the program
could likely be modified to achieve Credit Option #2 for areas that would be eligible for the leaf
management credit.
4.3.3 Phosphorus Reduction Credit from Leaf Management
The potential phosphorus reduction credit that could be achieved through the City’s leaf
management program was calculated. The “with controls” database was utilized to calculate the
pollutant loads from eligible areas and the associated numeric credit was applied. As part of the
analysis, it was assumed that the requirements for WDNR Numeric Credit Option #2 would be
followed for eligible land use areas. The results are summarized in Table 4-4.
Table 4-4. Potential Phosphorus Reduction Credit (WDNR Numeric Credit Option #2)
Reachshed
TMDL
Target TP
Load
Reduction
%
Existing TP
Reduction %
(compared to
“no controls”
total load)
Eligible
Area
(acres)
Potential
Increased
TP Load
Reduction
(lbs/year)
Potential
Increased TP
Reduction %
(compared to
“no controls”
total load)
Potential Total
TP Reduction
% (compared
to “no
controls” total
load)
Is TP Load
Reduction
Target
Met?
Upper Fox/Wolf TMDL Reachsheds
Sawyer Creek 85.6% 20.2% 16.5 1.98 0.1% 20.2% No
Fox River – Lake Butte
des Morts to Lake Winnebago 85.6% 28.6% 0.8 0.09 <0.00% 28.6% No
Totals 24.2% 17.3 2.07
4.4 Regional SMPs
The City of Oshkosh currently has 13 regional SMPs treating stormwater discharges from over
16 percent of the area analyzed in this study, scattered across the City, as presented in Section
City of Oshkosh Stormwater Quality Management Plan Section 4
4-7
Oshkosh SWMP Final
3.3.4 of this report. The City has successfully used this technique to reduce stormwater pollutant
discharges and will continue to evaluate locations of potential future practices; however, finding
locations to put regional detention where there is not already existing development or where
hydraulics work well is challenging.
Regional SMPs were also evaluated as part of past Citywide SWMP efforts in 2008 and 2014. As
part of these plans, an SMP identification number and name were given to each site considered. This
study continues to use the numbers from the past studies. Sites from the 2008 and 2014 Citywide
plans had identification numbers from 1 through 36.
Potential regional SMP sites considered as part of past studies were considered and incorporated
into this study. As part of these previous studies there were sites identified that were removed from
further consideration during those studies. These sites were not considered for regional SMPs as
part of the current study. Table H-1 in Appendix H provides a summary of the sites that were
previously considered but were removed from consideration. Figure H-1 in Appendix H provides a
location of those sites.
In the 2014 Citywide SWMP, a total of 12 regional sites were evaluated and considered for
implementation. Since that plan, three SMPs were implemented (South Park Basins Expansion [SMP
ID 4], 9th Ave & Washburn St [SMP ID 31], Libbey Ave/Nicolet Ave [SMP ID 36]). The nine remaining
sites were considered as the starting point for the current analysis. In addition, as part of this current
study, a review of other potential regional SMP sites was conducted throughout the City. This review
was conducted by:
1. Considering recent flood studies and reviewing the potential for pollution reduction from flood
mitigation practices recommended in those studies.
2. Reviewing GIS data and aerial photography to identify open space where regional SMPs could be
constructed.
3. Discussions with City staff regarding their local knowledge and ideas for new SMP sites.
The evaluation of regional SMPs included considering the potential for retrofitting existing practices.
Retrofits that were considered as part of this effort included; the feasibility of converting existing dry
detention basins into wet detention basins and the potential to expand existing wet detention basins
into adjacent open space. Through this process, a total of 11 potential new sites were identified.
These sites were identified as SMP identification numbers 37 through 47.
A feasibility screening of the potential sites, including those from the 2014 Citywide SWMP and
newly identified sites, was conducted to determine potential barriers to implementation. The
screening included consideration of WDNR wetlands/waterways, FEMA floodplains, potential for
environmental contamination, potential for natural heritage concerns, tailwater, whether they are in-
series with other SMPs, and major utility conflicts such as ANR pipelines or ATC power lines. These
sites were then discussed with, and reviewed by, City staff to gather additional input and insight into
the potential for implementation. As a result of the screening and discussions, six newly identified
sites were identified for further evaluation. All of the sites from the 2014 Cityside SWMP were also
advanced for further evaluation.
In addition to the six new sites that were evaluated, five other sites that were identified did not have
a detailed analysis completed for various reasons. Table H-2 and Figure H-2 in Appendix H provides
the location of these sites and the reason a detailed analysis was not completed.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-8
Oshkosh SWMP Final
4.4.1 Regional SMP Evaluation
The nine sites from the 2014 Citywide SWMP and six additional new sites were advanced and
evaluated further as part of this study. Their locations are shown on Figure 4-5. The following tasks
were completed for each SMP.
1. Available data from past studies were collected and utilized as part of the regional SMP
evaluation.
a. For all sites evaluated as part of the 2014 Citywide SWMP the data from that plan was
utilized as a starting point.
b. Washburn St/Westowne Ave Basin (SMP ID 6): This SMP was identified and evaluated as
part of the 2008 and 2014 Citywide SWMPs. A WDNR grant application was previously
prepared, and the City has completed a design for the basin expansion. The land acquisition
for the basin is currently ongoing. The WinSLAMM model from the grant application was
utilized as part of this study. The model was updated to reflect the current design as part of
this study.
c. Pheasant Creek Dry Basin (SMP ID 7): This SMP was identified and evaluated as part of the
2008 and 2014 Citywide SWMPs. The site was also evaluated as part of the West 9th
Avenue Reconstruction Storm Water analysis. The West 9th Avenue reconstruction project
considered the potential to retrofit this dry basin and provide storm water pollution control
for the West 9th Avenue reconstruction. Drainage basin delineations and WinSLAMM
models were developed as part of the prior project and were utilized as part of this study.
d. Hoffmaster East and West (SMP IDs 37 and 38): The concept for these wet detention basins
was developed as part of the Fernau Avenue Watershed Regional Stormwater Management
Plan. This plan was a detailed hydrologic and hydraulic analysis of the Fernau Avenue
Watershed that also included stormwater pollution planning and analysis elements.
Drainage basin delineations and WinSLAMM models were developed as part of the prior
project which were utilized as part of this study.
e. Lakeshore Park Ponds (SMP ID 39): The hydrologic and hydraulic performance of the
existing Lakeshore Park ponds were evaluated as part of the TID #34 and #35 Stormwater
Analysis. Stormwater pollution benefits from these ponds were not considered at that time.
Drainage basin delineations were developed as part of the prior project which were utilized
as part of this study.
2. The drainage area for each site was delineated. For sites previously evaluated, the drainage area
delineation from the prior projects was reviewed and updated as needed.
3. The available space for a potential SMP was considered and a conceptual stage-area
relationship was developed. The relationship developed utilized the “Create Pond Stage-Area
Values” tool within WinSLAMM. The stage area was developed based on the available area (top
area of the pond) and the pond depth required based on site topography and storm sewer depth.
A pond side slope of 4:1 above the normal water level, 10-foot safety shelf, and side slope of 3:1
below the normal water level was assumed.
4. The potential pollution control that could be achieved by a site was evaluated in WinSLAMM. As
part of the 2014 Cityside SWMP, the potential pollution control was evaluated using the
permanent pool guidelines from Appendix A of WDNR Technical Standard 1001. The stage-area
relationship developed for each site was used in the model.
A summary of the estimated pollution reduction that could be achieved by the potential regional
SMPs is provided in Table 4-5. Additional detail regarding the site screening and technical feasibility
is provided in Table H-3 in Appendix H. Details regarding the WinSLAMM modeling for the regional
City of Oshkosh Stormwater Quality Management Plan Section 4
4-9
Oshkosh SWMP Final
SMPs is included in Table H-4 in Appendix H. Figures H-3 through H-16 show the drainage area and
concept area of each potential regional SMP in Appendix H.
Table 4-5. Potential Regional Stormwater Management Practices Performance Summary
TMDL
Reachshed
Potential Regional Practice
Name and SMP ID
Drainage
Area (ac)
TSS
Reduction
(tons/year)
TSS
Reduction
(%)
TP
Reduction
(lbs/year)
TP
Reduction
(%)
Sawyer Creek Pheasant Creek (SMP 7) 241.0 3.3 62% 18.0 43%
Miles Kimball (SMPs 16A &
16B) 36.4 6.2 82% 15.8 57%
Oakwood & 20th Ave (SMP
29A) 60.4 9.4 81% 25.7 57%
Fox Tail Lane (SMP 29B) 162.1 15.0 80% 55.6 56%
Oakwood & 20th Ave/Fox Tail
Lane (SMPs 29A & 29B) 162.1 15.7 83% 56.1 56%
Westhaven Golf Course West
(SMP 35) 235.2 15.3 82% 91.1 61%
Sawyer Creek – Abbey Ave
(SMP 42) 81.2 6.6 80% 6.8 62%
Sawyer Creek – Golden Ave
(SMP 43) 76.2 6.0 77% 32.1 58%
Reachshed Totals1* 719.5 40.9 198.8
Lake Butte des
Morts
Washburn St / Westowne Ave
(SMP 6) 77.3 1.9 73% 0.1 50%
Lakeshore Park (SMP 39) 73.9 4.7 95% 29.4 68%
Riverside – North (SMP 40) 101.4 4.3 82% 24.6 60%
Reachshed Totals 252.6 10.9 54.1
Lake
Winnebago Island View Estates (SMP 15) 45.4 2.2 93% 13.0 62%
26-Bowen Street (SMP 26) 229.1 12.8 59% 52.5 40%
Hoffmaster - East & West
(SMPs 37 & 38) 173.1 20.9 74% 58.4 53%
Reachshed Totals 447.6 35.9 123.9
1Reachshed totals include SMPs 7, 29A/29B, 35 and 43. Other SMPs are upstream of the SMPs included.
4.4.2 Regional SMP Cost Considerations
Cost estimates were developed for each of the sites considered. For each site, a construction cost,
land acquisition cost, annual operation and maintenance cost, and dredging cost was developed.
Table 4-6 summarizes the annualized cost information for comparison. Construction cost estimates
were prepared based on unit costs from similar past construction projects. Average unit costs were
developed by BC and reviewed by City staff. Further details on the cost estimates including capital
cost to construct the facility, land acquisition cost, annual maintenance cost, and future dredging
cost are included in Appendix H as Tables H-5 and H-6.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-10
Oshkosh SWMP Final
Table 4-6. Potential Regional Stormwater Management Practices Cost Summary
Pond Name
TSS
Reduction
(tons/year)
TP
Reduction
(lbs/year)
Total
Annualized
Cost
Annual Cost
per Ton of TSS
Removed
Annual Cost
per Pound of
TP Removed
6-Washburn St/Westowne Ave Basin 1.9 0.1 $21,461 $11,295 $214,606
7-Pheasant Creek Dry Basin 3.3 18.0 $50,967 $15,444 $2,831
15-Island View Estates Dry Basin 2.2 13.0 $52,780 $23,991 $4,060
16A– Miles Kimball Dry Basin 3.6 9.1 $25,116 $6,977 $2,760
16B– Miles Kimball Dry Basin 2.1 5.5 $23,049 $10,976 $4,191
26-Bowen Street 12.8 52.5 $87,997 $6,875 $1,676
29A-Oakwood & 20th Ave 9.4 25.7 $92,524 $9,843 $3,600
29B-Fox Tail Lane 15.0 55.6 $53,426 $3,562 $961
29A/29B-Oakwood & 20th Ave/ Fox
Tail Lane 15.7 56.1 $145,950 $9,296 $2,602
35-Westhaven Golf Course West Basin 15.3 91.1 $96,584 $6,313 $1,060
37/38-Hoffmaster - East & West 20.9 58.4 $279,007 $13,350 $4,778
39-Lakeshore Park Ponds 4.7 29.4 $44,688 $9,508 $1,520
40-Riverside - North 4.3 24.6 $32,307 $7,513 $1,313
42–Sawyer Creek – Abbey Ave 6.6 33.6 $56,803 $8,607 $1,691
43-Sawyer Creek – Golden Ave 6.0 32.1 $29,210 $4,868 $910
4.4.3 Regional SMP Feasibility Summary
Following the evaluation of the regional SMPs, the sites were discussed further with City staff to
review feasibility and identify any additional concerns. As a result of these discussions, the following
conclusions were made.
• The Riverside – North (SMP ID 40) site was eliminated from further consideration for
implementation. Internal City discussions identified that the area targeted for this SMP is
planned for future cemetery expansion.
• The Sawyer Creek – Abbey Ave (SMP ID 42) and Sawyer Creek - Golden Ave (SMP ID 43) sites
are located within City park land. Construction of a pond in either of these locations would
require tree removal. An evaluation of tree species, sizes, and quality would need to be
conducted prior to the project proceeding. Additionally, input would be needed from the City’s
Advisory Park Board. Both of these sites are also located in proximity to ATC power lines. In
particular, the Sawyer Creek – Golden Ave (SMP ID 43) site would likely require the relocation of
a power pole for the lines. These factors would need to be considered and addressed as part of
a preliminary engineering study for these sites.
• The other sites considered are believed to be feasible. Unique situations are present with each
site and considerations are noted in the tables provided in the appendix.
4.5 Enhanced Settling for Phosphorus Removal
Conventional stormwater treatment ponds trap particulate pollutants when stormwater is held for a
period of time and allowed to settle out. The amount of particulate pollutants that are trapped
depends on several factors, including the residence time of the pond and the density of the particles.
For TP, a stormwater pond generally traps only the particulate form of phosphorus, and most of the
dissolved form is not retained. The dissolved form of phosphorus can account for 50 percent or more
of the TP load in stormwater.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-11
Oshkosh SWMP Final
A method to increase the phosphorus trapping efficiency of stormwater ponds is to use coagulants.
Aluminum-based coagulants have been shown to enhance removal of both particulate and dissolved
phosphorus by causing flocculation. Coagulant treatment of stormwater was first used in the
southeast United States in the late 1980’s. Typical systems for coagulant treatment of stormwater
consists of the following:
1. A coagulant injection system to add a coagulant, in the proper dose, to raw stormwater
2. A rapid mixing chamber to achieve thorough and complete mixing of the coagulant with the
stormwater
3. A pond to settle and trap the flocculant
4. Treated water discharge from the settling pond
The treatment system generally is housed in a small building with power, pumps, instrumentation,
and storage tanks for the coagulant.
Before implementing a coagulant treatment system, pilot testing of specific coagulant compounds
for a site’s stormwater is conducted to determine the optimum treatment. Testing has shown that
TP reductions in stormwater of 85 to 95 percent can be achieved. This is in comparison to the
conventional stormwater pond TP treatment reductions of 40 to 60 percent. To be conservative, a
TP reduction of 85.6 percent (equal to the TP reduction required to comply with the Upper Fox/Wolf
TMDL) will be assumed for pollutant removal and cost effectiveness analyses. Testing has also
shown that TSS reductions of greater than 90 percent can be achieved and this value was assumed
for the analysis.
4.5.1 Enhanced Settling Site Selection & Performance Analysis
An initial screening of potential sites to implement this practice was conducted by reviewing each of
the regional SMPs for the potential to retrofit them with a treatment system. The potential removal
that could be achieved through enhanced settling was estimated and site attributes were
considered. This is summarized in Table H-7 in Appendix H. The sites were discussed with the City
and four locations, Fair Acres/Murdock, Libbey-Nicolet, Fernau Watershed – North Main Street Area,
and 9th & Washburn regional SMPs, were selected for additional evaluation. The following
paragraphs describe the steps that were taken to evaluate the four sites. The results of this
evaluation are summarized in Table 4-7 and additional details are provided in Table H-8 in Appendix
H.
• The residence time of the pond was calculated. Three hours of residence time is considered a
minimum value; however, for conservative design purposes, a minimum residence time of six
hours is used. The residence time was calculated using the total storage volume (including all
volume below the emergency spillway). The design flow rate was identified as the maximum
pond inflow rate from the WinSLAMM detailed output file. For planning purposes, the five highest
inflow rates in the WinSLAMM model were considered. To calculate the residence time, the
inflow rate is multiplied by the desired residence time to calculate the volume required.
The results of the residence time calculations are summarized in Table H-8. Based on this
evaluation, the Fair Acres/Murdock wet detention basin would not be a feasible location for
enhanced settling because of inadequate storage volume. The Libbey-Nicolet, Fernau Watershed
– North Main Street Area, and 9th & Washburn sites appear feasible. The 6-hour residence time
criteria is not met for the largest storm event, but is met for all other events. The largest event is
significantly larger than other rainfalls in the rainfall series. System controls could be utilized to
turn off the treatment system during extreme rainfall events. Additionally, it may be feasible to
deepen the 9th & Washburn basin to provide additional volume.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-12
Oshkosh SWMP Final
• A capital cost estimate for each treatment system was developed. Many of the costs associated
with an enhanced settling treatment system are consistent between projects. For instance, the
equipment building, system telemetry, and water quality monitoring stations are anticipated to
be the same across all projects. Other costs are anticipated to vary based on the site
characteristics. Pertinent characteristics that influence cost include the number of inlets, where
the equipment building can be located on-site, and the distance from the building to inlet
locations. Construction drawings for each site were reviewed and cost estimates were
developed. Detailed information on the construction cost estimates is provided in Appendix H in
Table H-9.
• An annual operation and maintenance cost estimate for each treatment system was developed.
The operation and maintenance costs include fixed costs such as weekly site visits, testing, and
supplies, and, also, variable costs such as coagulant purchase, floc removal (dredging), and
power costs. Detailed information on the operation and maintenance cost estimates is provided
in Appendix H. It should be noted that dredging equipment is needed to complete floc removal.
The cost for this equipment (currently estimated at $250,000) is not included in the current
estimates as this item could be shared among facilities.
• Potential site constraints for each location were identified and are summarized on Table H-8 in
Appendix H.
Table 4-7 summarizes the potential TSS and TP reductions and the annualized costs associated with
the treatment systems considered.
Table 4-7. Potential Enhanced Settling Analysis Summary
SMP Name Treatment
Area (ac)
Potential
TSS
Reduction
(tons/year)
TSS
Reduction
(%)
Potential
TP
Reduction
(lbs/year)
TP
Reduction
(%)
Total
Annualized
Cost
Annual
Cost per
Ton of
TSS
Removed
Annual
Cost per
Pound of
TP
Removed
Fair Acres/Murdock 93.0 3.1 90% 26.4 85.6% $80,712 $26,017 $3,061
Fernau Watershed –
North Main Street Area 151.1 0.9 90% 29.5 85.6% $92,697 $107,967 $3,148
Libbey-Nicolet 418.6 10.4 90% 105.9 85.6% $144,246 $13,828 $1,362
9th & Washburn 366.2 2.2 90% 60.1 85.6% $86,168 $39,148 $1,434
The annual cost per ton of TSS removal varies significantly in the sites considered. A large factor in
this variability is the high level of existing TSS reduction that is achieved by the existing SMPs. For
example, the Fernau Watershed – North Main Street Area detention basin already reduces TSS by
87 percent in existing conditions. Enhanced settling will not increase the TSS reduction rate of this
pond much. The estimated annual cost per pound of TP reduction ranges from $1,300 to $3,200 per
annual pound of TP reduction. This cost is similar to the most cost effective traditional regional wet
ponds considered as part of this study.
Enhanced settling is an emerging technology in Wisconsin and a system has not been implemented
in Wisconsin at this time. One limitation is the lack of WDNR guidance on the technology, along with
the inability to model the practice in WinSLAMM. The WDNR is in the beginning stages to develop a
technical standard and/or guidance related to enhanced settling. This guidance may result in
changes to assumptions in the analysis and changes to the results. It is recommended that future
guidance and standards be further reviewed when available and this analysis can then be updated.
Additionally, the analysis assumes that floc generated by the facility can be disposed of to the
City of Oshkosh Stormwater Quality Management Plan Section 4
4-13
Oshkosh SWMP Final
sanitary sewer, and ultimately, the City’s wastewater treatment plant. This type of disposal has been
successful and accepted by other wastewater treatment plants in locations where these systems
exist. The feasibility of this disposal method will need to be further evaluated and verify that disposal
does not create issues for the wastewater treatment plant. Alternatively, floc can be removed from a
pond, dewatered, and disposed of. In this case, a disposal location would need to be identified.
4.6 Engineered Swales
The 2014 Citywide SWMP considered the potential for creation of engineered swales. Engineered
swales consist of excavating soil from the bottom of the existing swale (approximately 3 feet), placing
an underdrain pipe, and replacing the native soil with an engineered soil. The underdrain pipe is then
connected to an existing storm sewer. As part of the 2014 Citywide SWMP, engineered swales were
identified in the areas currently identified as Swale Groups 05 (located north of STH 21, along Omro
Rd) and 07 (along Washburn St between 20th Ave and Dickinson Ave).
All of the swales included as part of the existing conditions were evaluated for the feasibility / benefit
of conversion to engineered swales. The analysis considered the following information.
• Swales achieving a TP reduction greater than 85.6 percent (the reduction target associated with
the Upper Fox/Wolf TMDL) were eliminated from consideration as they were already providing
pollution control in excess of the required target. This eliminated all swales except Swale Groups
05 and 07.
− Swale Group 05 is located in the Lake Butte des Morts reachshed and achieves a TSS
reduction of 41.4-percent and a TP reduction of 35.4-percent.
− Swale Group 07 is located in the Fox River and Sawyer Creek reachsheds and achieves a
TSS reduction of 62.8-percent and a TP reduction of 58.7-percent. However, this swale
group is located upstream of the existing 9th & Washburn and Armory regional wet
detention basins. The detention basins achieve higher levels of control (Armory = 92.7-
percent TSS/79-percent TP, 9th & Washburn = 83.2-percent TSS/61.1-percent TP).
• WDNR guidance for pollution reduction from filtering through engineered soil were considered.
The guidance document “Modeling Post-Construction Storm Water Management Treatment,”
February 2020, provides details regarding allowable TSS and TP reduction credits associated
with engineered soil. This guidance document is included in Appendix B.
− If an engineered soil mix (consisting of compost and sand) meeting WDNR Technical
Standard 1004 (Bioretention) is utilized, a TSS removal credit of 80-percent is given. No TP
reduction credit (0-percent removal) is given.
− As opposed to engineered soil, a sand filter could be utilized, which is given a filtering credit
of 80-percent for TSS and 35-percent for TP.
− The guidance document notes that the WDNR and USGS are trying to develop an engineered
soil mix that will reduce TP through filtering.
Thus, based on current guidance, engineered swales are not a feasible practice to increase the TP
removal above what is achieved by the current grass swales.
4.7 Biofilters and Rain Gardens
The use of biofilters and rain gardens to achieve pollution control targets was considered in both the
2008 and 2014 Citywide SWMPs. Both plans identified the use of biofilters to treat industrial lands
as a means to meet pollution reduction targets. The prior analysis evaluated biofilters and rain
gardens at a land use/regional level. Meaning that specific locations for these practices were not
City of Oshkosh Stormwater Quality Management Plan Section 4
4-14
Oshkosh SWMP Final
considered, instead the analysis focused on the impacts to pollution reductions if practices were
implemented on a large scale across the City.
The prior analysis was reviewed and updated as part of this study. The analysis is described in the
following sections.
4.7.1 Rain Gardens
Rain gardens are “a shallow depression planted with a dense cover of vegetation, designed to
capture storm water runoff from a small drainage area and infiltrate it into the underlying soil”
(WDNR Technical Standard 1009). Most frequently rain gardens are implemented in residential
settings to treat roof runoff. WDNR Technical Standard 1009 provides technical criteria for siting,
sizing, and implementing rain gardens to comply with infiltration criteria, a copy of this technical
standard is included in Appendix B. There are various additional resources that provide information
regarding rain garden design and construction.
To evaluate the potential pollution reductions that could be achieved by rain gardens, WinSLAMM
models were developed. The analysis was conducted using the 100-acre Medium Density
Residential – No Alleys (MDRNA) standard land use file and assumed different levels of rain garden
implementation. Rain gardens were sized following WDNR Technical Standard 1009 to infiltrate
approximately 90 percent of runoff volume from a portion of the roofs within the analysis area.
Table 4-8 summarizes the results of the analysis and includes assumptions/key parameters
included in the analysis.
Table 4-8. Rain Garden Evaluation - Potential Annual Pollution Reductions (per 100 acres)
Ratio of Rain
Gardens per Parcel
Number of Rain
Gardens % TSS Reduction1 TSS Removed per
100 acres (tons/yr) % TP Reduction1 TP Removed per
100 acres (lbs/yr)
Every House 400 2.8% 0.3 3.2% 2.6
50% of Houses 200 1.4% 0.2 1.6% 1.3
25% of Houses 100 0.7% 0.1 0.8% 0.7
Assumptions.
1. Land use is Medium Density Residential – No Alleys and the average lot size is ¼ acre.
2. Average roof area is 1,635 sq. ft. per lot. Rain gardens treat ¼ of the total roof area.
3. Rain Garden Sizing / Parameters
a. Area = 100 sq. ft.
b. 0.25-ft ponding depth
c. Infiltration Rate = 0.15 inches/hour for Clay Loam soils as per WDNR Technical Standard 1009
1Percent pollutant reductions are reported per 100-acres. Rain gardens infiltrate 93-percent of runoff volume from the tributary area (410
sq. ft. of roof area)
4.7.2 Biofilters
Biofilters are a widely used SMP that consist of a planted engineered soil area consisting of compost
and sand. Below the engineered soil area is an underdrain pipe and stone storage area. Runoff is
directed to the device and flows through the engineered soil. The runoff then either infiltrates into
the native soil or is collected by the underdrain pipe and discharged from the biofilter. Pollutants are
removed through either filtering in the engineered soil area or by infiltrating into the native soil. The
WDNR has Technical Standard 1004 (included in Appendix B) for biofilters and there is additional
City of Oshkosh Stormwater Quality Management Plan Section 4
4-15
Oshkosh SWMP Final
guidance in the document “Modeling Post-Construction Storm Water Management Treatment,”
February 2020.
Research has recently shown that biofilters using the engineered soil mix in WDNR Technical
Standard 1004, which includes 15 to 30 percent compost, does not achieve a reduction of TP. As
per WDNR guidance “Modeling Post-Construction Storm Water Management Treatment,” February
2020, if an engineered soil mix meeting WDNR Technical Standard 1004 is utilized, a TSS removal
credit of 80-percent is given. No TP reduction credit (0-percent removal) is given. In lieu of
engineered soil, a sand filter could be utilized, which is given a filtering credit of 80 percent for TSS
and 35 percent for TP. For the purposes of this study, the biofilter evaluation assumes a sand filter is
utilized and a 35-percent TP filtering reduction is achieved. This is the highest TP reduction that can
be achieved following current guidance.
The potential pollution reduction that could be achieved by biofilters was evaluated on a per acre
basis. Biofilters would be targeted to treat land uses that produce higher amounts of pollutants.
Thus, this analysis considered commercial, industrial, and institutional land uses. A representative
standard land use from each of these generalized land use categories was identified. A biofilter was
then sized to provide 80-percent TSS treatment from one-acre of that land use. Model input
parameters consistent with WDNR Technical Standard 1004 and the WDNR modeling guidance were
used. The biofilter sizing and associated potential pollutant reductions are summarized in Table 4-9.
Table 4-9. Biofilter Evaluation - Potential Annual Pollution Reductions (per acre)
Land Use Biofilter Size
(sq. ft.) % TSS Reduction TSS Removed per
Acre (tons/yr) % TP Reduction1 TP Removal per
Acre (lbs/yr)
Shopping Center 1025 80.2% 0.2 43% 0.4
Light Industrial 800 80.4% 0.2 42% 0.4
School 650 80.4% 0.1 42% 0.4
Biofilter Design Parameters.
1. Engineered Soil: Depth = 3-ft, Porosity = 0.27, Infiltration Rate = 3.6-inches/hour, TSS Reduction = 80%
2. Stone Storage: Depth = 1-ft, Porosity = 0.33
3. Outlets: 6-inch underdrain at 0.5-ft depth, 12-inch standpipe at 5-ft, overflow weir at 5.5-ft
4. Native Soil Infiltration Rate = 0.07 inches/hour
1Filtering reduction through engineered soil = 35%, infiltration reduction = 100%
One item that can cause a significant difference in the results of the analysis is the assumed
infiltration rate. The infiltration rate selected with the analysis follows WDNR Technical Standard
1002 and is representative of clay soils without field measurements. Field measurements from
swale testing has shown higher infiltration rates present in the City. It is possible that field testing for
infiltration through biofilters would show higher infiltration rates. This could result in higher TP
removals, in excess of 80 percent, as any volume that infiltrates results in a 100-percent pollutant
reduction. There are differences between the grass swales where infiltration testing occurred and
potential biofilter locations. Biofilters would be implemented within developed sites and are
frequently implemented in areas such as parking lots (by removing a portion of the lot) or the
perimeter of lots. These areas are often compacted by prior construction activities. The grass swales
have been in existence for a significant period of time and are vegetated, which likely allowed
compaction from construction to be mitigated. This item could be considered in the future to further
evaluate biofilters as a mechanism for TMDL compliance.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-16
Oshkosh SWMP Final
4.7.3 Biofilter and Rain Garden Widespread Implementation Impacts & Summary
To consider the potential impact of widespread implementation of biofilters, the “with controls”
database was utilized to identify areas not otherwise treated with existing structural SMPs. The level
of pollution control that could then be achieved by implementing biofilters onto a percentage on
these lands was then calculated by reachshed.
Construction costs associated with biofilters from past City construction projects were reviewed. Bid
results from the City Lakeshore Park Four Seasons Building (constructed in 2022) were utilized to
develop a construction cost estimate of approximately $32 per square foot of biofilter footprint. An
operation and maintenance cost estimate per biofilter was developed based on guidance from the
Minnesota Storm Water Manual.
Research into typical costs for rain gardens was also conducted. Rain gardens are frequently
constructed by homeowners as do-it yourself projects at a limited cost. In this case, the only cost
associated with rain garden construction is the purchase of native plant plugs, which typically ranges
from $3 to $5 each (source: “UW-Extension; How To Build a Rain Garden”). Landscape contractors
also construct rain gardens at costs in the range of $1,000 to $2,500 (sources: UW-Extension and
the City of Madison).
The costs of rain gardens and biofilters and the annualized cost of TSS control is summarized in
Table 4-10. A more detailed evaluation of the amount of pollution control (TSS and TP) that could
potentially be obtained and the annualized costs is included in Table I-1 in Appendix I.
Table 4-10. Biofilter/Rain Garden Cost Evaluation
Land Use TSS Removed per
Acre (tons/yr)
Construction Cost
per Rain
Garden/Biofilter
Estimated Annual
Maintenance Cost
Total Annualized
Cost
Annualized Cost
per ton of TSS
Removal
Residential 0.001 $1,250 $0 $40 $50,000
Shopping Center 0.2 $25,600 $3,150 $3,962 $19,000
Light Industrial 0.2 $20,800 $2,850 $3,509 $25,000
School 0.1 $32,800 $3,500 $4,540 $30,000
The results of the analysis showed that costs associated with rain gardens are higher than costs for
other SMPs for TSS reduction. In addition, the total pollution reduction associated with rain gardens
is small. Even with large-scale implementation of rain gardens, the associated pollution reductions
are limited. For example, in the Sawyer Creek watershed, if rain gardens are installed on 25 percent
of residential properties not treated by existing SMPs, an annual TP reduction of 1 pound per year
would be achieved (see Table I-1). This is due to the rain gardens treating what is generally a clean
source of runoff (residential roofs). This limits the benefits associated with rain gardens in terms of
complying with the TMDL requirements.
Biofilters can produce higher reductions from industrial, institutional, and commercial lands than
rain gardens. Generally, the cost of pollution removal from biofilters is higher than wet detention
ponds. Additionally, the analysis of rain gardens and biofilters was a widescale planning level
analysis. Individual site constraints and costs were not considered and can result in wide
fluctuations in costs. Site conditions such as needing to remove pavement for construction or
installing piping for an outlet can greatly increase project costs. Site conditions can also result in
areas where these practices cannot be implemented. For example, there are areas of the City that
are only slightly higher than the normal pool level of Lake Winnebago, the Fox River, and Lake Butte
City of Oshkosh Stormwater Quality Management Plan Section 4
4-17
Oshkosh SWMP Final
des Morts. Biofilters would need to be located at an elevation where the underdrain is above the
pool level to function properly.
The use of biofilters can be a tool to assist in meeting TMDL requirements. However, the limitation in
the TP reduction that can be achieved (only a 35-percent reduction for water filtered through the soil)
is an impediment to implementation of a wide-scale application. The use of biofilters on a case-by-
case basis as opportunities arise can be pursued (such as during redevelopment projects), and
biofilters will likely continue to be a SMP used by the development community.
The WDNR and USGS are trying to develop an engineered soil mix that will reduce TP through
filtering. One potential mechanism that could be utilized in the future is iron-enhanced sand
filtration. Research into this technology has been conducted by the University of Minnesota St.
Anthony Falls Laboratory. Currently, the “Minnesota Stormwater Manual” cites a 74-percent
reduction in TP from iron enhanced sand filters that meet their level 2 sizing criteria (providing full
water quality treatment, pretreatment, and a filter bed size that is greater than 5 percent of the
drainage area). This represents a large increase in the TP reduction that can currently be achieved
with a sand filter; however, it is still less than the 85.6-percent TP reduction needed to meet the
Upper Fox / Wolf TMDL. This technology, and other possible engineered soil mixtures, can be
monitored and the results of this analysis updated to reflect potential increased TP reductions.
4.8 Projected Development Pollution Control
As described in Section 3.3.5, there are numerous non-regional SMPs spread throughout the City of
Oshkosh. These non-regional SMPs were typically constructed as part of development projects that
were required to provide post-construction pollution reductions in accordance with City of Oshkosh
Municipal Code Chapter 14 and/or Wisconsin Administrative Code NR 151. As development
continues to occur within the City, there will continue to be additional non-regional SMPs installed.
Municipal Code Chapter 14 requires pollution control from both new development (80-percent TSS
reduction) and redevelopment (40-percent TSS reduction) sites. As per Municipal Code Chapter 14,
redevelopment and new development have the following definitions.
• Redevelopment means that portion of a post-construction site where impervious surfaces are
being reconstructed, replaced, or reconfigured. Any disturbance where the amount of impervious
area for the post-development condition is equal to or less than the pre-development condition
is classified as redevelopment.
• New development means that portion of a post-construction site where impervious surfaces are
being created or expanded. Any disturbance where the amount of impervious area for the post-
development condition is greater than the pre-development condition is classified as new
development.
For purposes of Chapter 14, a post-construction site is classified as new development,
redevelopment, or some combination of these classifications. Frequently sites are a combination of
these two development types and this results in what is called “mixed developments”. An example of
this would be a site where a parking lot is reconstructed (redevelopment) and a building expansion
and new parking lot is created (new development). In the case of mixed development, the pollution
reduction standards are pro-rated between the types of development.
As part of this Citywide stormwater quality plan, it was desired to understand the impacts that new
development, redevelopment, and mixed development will have on water quality pollutant loadings.
As the City grows and redevelops, there will be incremental impact, either positively or negatively, on
the City’s overall level of pollutant reduction which can provide some insight into how ordinance
changes could impact future pollution reductions. Some municipalities are changing their ordinances
City of Oshkosh Stormwater Quality Management Plan Section 4
4-18
Oshkosh SWMP Final
to require levels of pollution control/reduction consistent with TMDL requirements from new
development and redevelopment sites. These changes can provide incremental improvements in
water quality but also impact developers.
The evaluation of projected development pollution control considered the current Chapter 14
requirements, and, also, two ordinance modification scenarios. The scenario details and potential
impacts are summarized in Table 4-11. The analysis considered a 30-year planning horizon, with
interim results at 10- and 20-years.
Table 4-11. Projected Development Pollution Control Scenarios
Current Requirements Scenario #1 Scenario #2
Category TSS TP TSS TP TSS TP
Redevelopment 40% 27% 58.4% 39.4% 52% 35%
Mixed Development 60% 40.5% 72% 48% 71% 48%
New Development 80% 54% 85% 57.4% 90% 61%
Scenario Development Notes:
Current Code
Redevelopment & New
Development
TSS reduction requirements based on current code requirements.
TP reduction is assumed based on the treatment credit associated with 40% or 80% TSS reduction for a wet
pond. Current ordinance does not have a TP reduction requirement.
Scenario #1
Redevelopment Require TSS control of 58.4%. Equivalent to the TSS reduction required for Sawyer Creek reachshed.
Required TP reduction is calculated based on TP reduction associated with typical wet pond performance.
New Development
Increase TSS reduction by 5% as a "step-up" in reduction requirement. Requirement is slightly higher than reduction achieved by average new development site from 2014 - 2022.
Required TP reduction is calculated based on TP reduction associated with typical wet pond performance.
Scenario #2
Redevelopment Require a TP control of 35%. Based on feasible technology available per WDNR Technical Standards.
Required TSS reduction is calculated based on TP reduction associated with typical wet pond performance.
New Development
Increase TSS reduction by additional 5% over Scenario #1 as an additional "step-up" in reduction
requirement. This level was achieved by six sites from 2014 - 2022.
Required TP reduction is calculated based on TP reduction associated with typical wet pond performance.
All Scenarios
Mixed Development Requirement would be site specific. For analysis assume an equal ratio of redevelopment and new
development.
Average Pollution Reduction from Recent Development
Projects (2014 - 2022)
Category TSS TP
Redevelopment 47% 32%
Mixed Development 72% 49%
New Development 84% 60%
Typical reductions from past projects are above the current Municipal Code requirements. New development (and mixed development sites) are
required to also meet peak reduction requirements. The peak reduction requirements are typically the controlling factor in sizing of SMPs as part
of a development site and result in pollution reductions above target levels.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-19
Oshkosh SWMP Final
4.8.1 Redevelopment/Mixed Development
Redevelopments and mixed developments occur within the developed portion of the city limits. Both
of these types of projects are common, and have occurred throughout the city, since the 2014
Citywide SWMP. The impact of future redevelopment and mixed development areas on the City’s
ability to make progress towards meeting the various TMDL reachshed goals was evaluated. The
evaluation considered the current Municipal Code requirements, and, also, two potential scenarios
where the Municipal Code is modified to require increased TSS and/or TP reductions.
To evaluate the impact of redevelopment and mixed development, past data was utilized to estimate
the annual area associated with these types of developments. The projected TSS and TP reductions
that would be associated with these developments was then applied to understand the potential
Citywide impact of redevelopment and mixed development. The following steps summarize how the
analysis was conducted.
1. The analysis considered non-regional SMPs implemented since the 2014 Citywide SWMP. The
TSS reduction associated with each non-regional SMP was utilized to categorize the type of
development that each SMP was associated with.
a. If the TSS reduction was greater than 80 percent, the project was assumed to be new
development and it was removed from this analysis.
b. If the TSS reduction was less than 60 percent, the project was assumed to be
redevelopment.
c. If the TSS reduction was between 60 percent and 80 percent, the project was assumed to
be mixed development.
2. The area within the WinSLAMM model for each non-regional SMP was then tabulated to
calculate the area of both redevelopment and mixed development since 2014. Additionally, each
project was categorized into the reachshed where the project occurred. The total areas were
then converted into an average annual redevelopment and mixed development rate. Table 4-12
summarizes the areas of redevelopment and mixed development.
3. To evaluate the scenarios described above, the database used to develop the “with controls”
condition for this project was assessed. Then potential redevelopment or mixed development
areas were extracted for land uses that had no existing SMPs or had existing SMPs that were
underperforming the reductions required under the City’s ordinance (an existing TSS reduction of
less than 40 percent). Additionally, the database was further filtered to extract the areas
summarized in the following paragraphs. The available potential redevelopment area is shown
on Figure 4-6 and summarized in Table 4-12.
a. The existing land use was considered. Single family residential, open space, park, and
railroad lands were excluded from the available redevelopment area. Open space land
would be subject to new development requirements and the other lands are not typically
redeveloped.
b. Parcels that were less than 20,000 square feet were excluded. The Municipal Code is
applicable to projects with 20,000 square feet of impervious area impacts or greater. Thus,
parcels less than 20,000 square feet would not be impacted. An exception to this is if
parcels are aggregated; however, due to the planning level nature of this study, this
potential nuance was disregarded.
c. Right-of-way areas were removed as these areas are not typically subject to the current
municipal code.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-20
Oshkosh SWMP Final
Table 4-12. Average Annual Redevelopment & Mixed Development Area
Reachshed
2014-2022
Redevelopment
Area
Average Annual
Redevelopment
Area
2014-2022
Mixed
Development
Area
Average
Annual Mixed
Development
Area
Potential
Redevelopment
Area
(acres) (acres/year) (acres) (acres/year) (acres)
Sawyer Creek 13.0 1.9 17.9 2.6 727
Lake Butte des Morts 0.8 0.1 15.1 2.2 500
Fox River – Lake Butte
des Morts to Lake
Winnebago
157.7 22.5 8.2 1.2 694
Lake Winnebago 31.6 4.5 60.8 8.7 1,451
Totals 203.1 29.0 102.0 14.6 3,372
Analysis Methodology Notes
1. Utilized dataset of non-regional SMPs implemented after 2014 Citywide SWMP.
2. Identified SMPs installed as part of redevelopment of mixed development projects. Assumed redevelopment are projects with a TSS
reduction of less than 60%. Assumed mixed development is projects with a TSS reduction of 60% to 80%.
3. Calculated the area of each type of development by reachshed. Area of development is assumed to be equal to the WinSLAMM model
area.
4. Projects that had a TSS reduction of greater than 80% were assumed to be new development and were excluded from this analysis.
5. The Neenah Slough reachshed is excluded from analysis. Area within Neenah Slough reachshed would be considered new
development.
6. Potential redevelopment area is area currently achieving less than a 40% TSS reduction. Existing reductions from SMPs such as street
cleaning and catch basins is accounted for in the analysis.
Table 4-12 shows that on average, there are 29 acres of redevelopment and 15 acres of mixed
development on an annual basis Citywide. There are also about 3,370 acres of land available for
redevelopment or mixed development. At the recent rate of redevelopment and mixed
development this equates to about 75 years of development activity before the available land
would be expended. However, in the Fox River reachshed, the rate of development would expend
the available land in about 30 years. This is a result of recent large redevelopment projects in
the reachshed. To address this issue, the expected annual redevelopment area was adjusted to
eliminate that model area from the largest redevelopment project, which was considered an
outlier. This resulted in an adjusted redevelopment rate of 7.3 acres/year which was used for
planning projections.
4. The “no controls” and “with controls” TSS and TP loads from potential redevelopment areas
were calculated. For each of the scenarios considered, the incremental additional pollutant
reductions associated with the projected redevelopment and mixed development were then
calculated. The impact was summarized on a 10-, 20-, and 30-year projection for TSS and TP by
reachshed. A summary table (Table 4-13) below is provided showing the results from the
different scenarios at the 30-year projection. Detail tables (Tables J-1, J-2, and J-3) for each
scenario are included in Appendix J. The analysis assumed that no maximum extent practicable
(MEP) relief from the requirements is granted, but it is acknowledged that this may happen.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-21
Oshkosh SWMP Final
Table 4-13. Redevelopment Analysis Summary
Total Suspended Solids
Reachshed
Current Conditions 30-year Projection (2022 – 2051)
Total
Analyzed
Area (ac)
TMDL Target
TSS Load
Reduction %
With-Controls
TSS Reduction
% (compared to
“no controls”
total load)
Is TSS Load
Reduction
Target Met?
Current Code Scenario #1 Scenario #2
Incremental TSS
Reduction %
Future
Reachshed TSS
Reduction %
Incremental TSS
Reduction %
Future
Reachshed TSS
Reduction %
Incremental TSS
Reduction %
Future
Reachshed TSS
Reduction %
Is TSS Load
Reduction
Target Met?
Sawyer Creek 2,707 58.4% 27.8% No 3.0% 30.7% 4.0% 31.8% 3.8% 31.6% No
Lake Butte des Morts 2,137 20% 23.2% Yes 3.2% 26.3% 3.8% 27.0% 3.8% 27.0% Yes
Fox River – Lake
Butte des Morts to Lake Winnebago 3,452 20% 38.3% Yes 2.9% 41.2% 4.4% 2.7% 3.9% 42.2% Yes
Lake Winnebago 7,041 20% 30.8% Yes 3.9% 34.7% 5.1% 35.9% 4.9% 35.7% Yes
Total Phosphorus
Reachshed
Current Conditions 30-year Projection (2022 – 2051)
Total
Analyzed
Area (ac)
TMDL Target TP
Load
Reduction %
With-Controls
TP Reduction %
(compared to
“no controls”
total load)
Is TP Load
Reduction
Target Met?
Current Code Scenario #1 Scenario #2
Incremental TP
Reduction %
Future
Reachshed TP
Reduction %
Incremental TP
Reduction %
Future
Reachshed TP
Reduction %
Incremental TP
Reduction %
Future
Reachshed TP
Reduction %
Is TP Load
Reduction
Target Met?
Sawyer Creek 2,707 85.6% 20.2% No 1.6% 21.7% 2.1% 22.3% 2.0% 22.2% No
Lake Butte des
Morts 2,137 85.6% 18.3% No 1.7% 20.0% 2.0% 20.3% 2.0% 20.3% No
Fox River – Lake
Butte des Morts to
Lake Winnebago
3,452 85.6% 28.6% No 1.7% 30.3% 2.6% 31.2% 2.3% 30.9% No
Lake Winnebago 7,041 85.6% 24.8% No 2.0% 26.8% 2.6% 27.4% 2.4% 27.3% No
Note: Analysis projected the rate of redevelopment and mixed development and potential redevelopment areas were identified. Increased “no controls” loads and pollutant reductions associated with redevelopment were calculated for the
various Municipal Code Scenarios and these were applied to the loads from the potential redevelopment areas. These pollutant loads were added to the “no controls” and “with controls” pollutant loads calculated in this analysis and the change
in Citywide pollution reduction was calculated. Details regarding the steps completed, assumptions and inputs are provided in Section 4.8.1 and Appendix J.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-22
Oshkosh SWMP Final
The impact of redevelopment and mixed development does not result in any reachshed achieving a
TMDL goal within the 30-year planning horizon. In general, under Scenario #2, an incremental
increase in TP reduction by about 2 to 3 percent is projected from redevelopment and mixed
development.
It should also be noted that the potential redevelopment area accounts for land treated by existing
regional and non-regional SMPs. However, it does not account for potential regional SMPs which
were evaluated and discussed above in Section 4.4 that could be installed. In addition, the amount
of redevelopment area is far greater than the pace of development, and it will take many years
before available redevelopment land is expended. It is also assumed that the redevelopment occurs
outside of areas that are treated by regional SMPs. If redevelopment occurs within these areas, the
impact of the pollution control from redevelopment will be reduced.
4.8.2 New Development
The WDNR “TMDL Guidance for MS4 Permits: Planning, Implementation and Modeling Guidance”
requires the TMDL analysis area to include all land areas within its corporate boundary unless it is
listed as optional (e.g., riparian areas). Therefore, as the City grows, so will its “no controls” and “with
controls” pollutant loadings.
The Upper Fox/Wolf TMDL report states that a reserve capacity of 5 percent was set aside for future
discharges, changes in current discharge loading, and other sources not defined through the TMDL
associated with controllable loads (does not include background or general permitted baseline
loads); however, there is no direct application or allowance of new development to individual
municipalities or other sources of pollutant loads. When reviewing the Lower Fox River TMDL report,
that document states that the analysis did not include any reserve capacity for future growth of
municipalities. The two main factors attributed to the lack of any reserve capacity for MS4
communities are: (1) the expectation that often growth is attributed to the conversion of agricultural
land into urban land uses (which the report suggests TP and TSS loads may remain the same or
decrease but is not guaranteed), and (2) the need to comply with NR 151 and NR 216 requiring new
development to reduce pollutant loads.
As the City boundary expands or open land within the current City boundary develops (for areas not
already identified as developed), the impacts will be incorporated into future water quality plan
updates. The City of Oshkosh Comprehensive Plan Update 2040 was utilized to assist in projecting
future development. The City also provided a GIS dataset for future land use correlating with the
comprehensive plan. This data was used on the basis to evaluate the potential impact from new
development on pollution control in the City of Oshkosh. Similar to the analysis of redevelopment,
this project considered the impacts under the current Municipal Code and also the same two
alternative scenarios described in Section 4.8. The steps taken to complete the analysis are
described in the following paragraphs.
1. Areas within the current City limits that could potentially be developed were identified. The
existing conditions database for the project was utilized to calculate the area of land that is
currently identified as open space or agricultural land.
2. Potential development areas outside of the City limits were identified and categorized by
reachshed. The City-provided future land use dataset was used as the basis for this step. Maps
4-3A, 4-3B, 4-3C, and 4-3D from the Comprehensive Plan Update are included in Appendix J and
show the land use categories.
a. Protected areas were excluded from the analysis. Additionally, areas classified as rural
residential were eliminated from the analysis.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-23
Oshkosh SWMP Final
b. For the purposes of this study, the planning area was assumed to end at James Rd on the
west and Indian Point Rd on the north. The area is bounded by Lake Winnebago on the east
and protected areas to the south.
c. Rural residential land correlates with maximum housing densities of 1 unit per 35 acres and
represent housing in adjacent towns.
The data from the first two steps was tabulated to calculate the total available area for
development. The areas are shown in Figure 4-7.
3. The projected growth of the City was evaluated using two available datasets.
a. The change in the analyzed area between the prior (2014) and current (2022) SWMP was
compared. This showed an increase of approximately 720 acres over seven years. This
equates to slightly more than 100 acres per year of new development.
b. The project growth as per the “City of Oshkosh Comprehensive Plan Update 2040” was
considered. Chapter 4 of the plan includes projects on future land use consumption
(detailed in text starting on page 4-9 of the plan, and in tables 4-7 and 4-8 which provide low
and high estimates for projected growth). The low estimate for land use consumption is
66 acres, while the high estimate is 83 acres. This land use consumption is broken down
into different land use categories (commercial, industrial, and single and multi-family
residential). This projected growth does not account for right-of-way areas that are included
within the analyzed area of the 2014 and current Citywide SWMPs.
4. Based on the available data regarding the projected growth and in discussion with the City, a
projected new development rate of 80 acres per year was selected. This selection is based on
the growth since the 2014 plan and the City’s comprehensive plan.
5. Table J-4 in Appendix J provides the background data associated with the projected growth
analysis described in Steps 1 – 4.
6. The future land uses for undeveloped areas were categorized with a corresponding WinSLAMM
land use. This categorization was based on the descriptions of the land use provided in
Table 4-9 of City’s “Comprehensive Plan Update 2040”. The undeveloped areas were also
tabulated by reachshed, both in total area and by land use. Using the percentage of land use
within each reachshed, an average pollutant unit load associated with the new development
area was calculated for each reachshed. This step is summarized in Table J-5 in Appendix J.
7. It was assumed that new development would occur both within and outside of the City limits on
an annual basis. Currently, there is almost 2,000 acres of undeveloped land within the City
limits. This would equate to about 20 years of development growth at the projected growth rate
solely within the City limits. It is known that growth does occur outside of the City limits. Thus, it
was assumed that the development of the undeveloped area within the City limits would occur
evenly through the 30-year planning horizon. Thus, approximately 80 percent of the new growth
would occur outside the City limits and 2/3 would occur within.
8. The estimated annual new development rate was calculated for each reachshed based on the
available development land in the reachshed (i.e., if 29 percent of the available development
area is within the Sawyer Creek reachshed, 24 acres per year of growth would occur within this
reachshed).
9. The annual increase in base load from new development areas was calculated using the unit
load determined in Step 6. This unit load was reduced based on the base load from open space
areas within the City limits that are accounted for in the analysis.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-24
Oshkosh SWMP Final
10. The annual new development load reduction from new development areas was then calculated
for each scenario (i.e., the TSS base load was multiplied by the TSS reduction requirement from
the Municipal Code to calculate the load removed).
11. Table J-6 in Appendix J provides the background data associated with Steps 6 – 10.
12. Using the data generated in the steps above, the projected analyzed area, projected base load,
projected “with controls” load reduction, and projected “with controls” percent pollution
reduction was calculated for each of the three Municipal Code scenarios.
13. Table 4-14 below summarizes the results of the new development analysis over the 30-year
planning horizon. Tables J-7, J-8, and J-9 in Appendix J provide more detailed information
regarding the projections at the 10-, 20-, and 30-year points. This analysis shows that the TMDL
requirements for the Neenah Slough reachshed can be met through new development occurring
in this reachshed.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-25
Oshkosh SWMP Final
Table 4-14. New Development Analysis Summary
Total Suspended Solids
Reachshed
Current Conditions
Estimated
Annual New
Development
Area
30-year Projection (2022 - 2051)
Total
Analyzed
Area (ac)
TMDL Target
TSS Load
Reduction %
With-Controls
TSS Reduction
% (compared to
“no controls”
total load)
Current Code Scenario #1 Scenario #2
Projected
Analyzed
Area
Projected “With
Controls” TSS
Load Reduction
%
Is TSS Load
Reduction
Target Met
Projected
Analyzed
Area
Projected “With
Controls” TSS
Load Reduction
%
Is TSS Load
Reduction
Target Met
Projected
Analyzed
Area
Projected “With
Controls” TSS
Load Reduction
%
Is TSS Load
Reduction
Target Met
(acres) (acres) (acres)
Sawyer Creek 2,707 58.4% 27.8% 24 2,834 42.1% No 2,834 43.4% No 2,834 44.8% No
Lake Butte des Morts 2,137 20% 23.2% 30 2,296 41.2% Yes 2,296 42.7% Yes 2,296 44.2% Yes
Fox River 3,452 20% 38.3% 2 3,462 38.9% Yes 3,462 38.9% Yes 3,462 39.0% Yes
Lake
Winnebago 7,041 20% 30.8% 23 7,165 36.3% Yes 7,165 36.9% Yes 7,165 37.4% Yes
Neenah
Slough 35 52% 0% 2 45 61.3% Yes 45 65.2% Yes 45 69.0% Yes
Total 15,371 80 17,771 17,771 17,771
Total Phosphorus
Reachshed
Current Conditions
Estimated
Annual New
Development
Area
30-year Projection (2022 - 2051)
Total
Analyzed
Area (ac)
TMDL Target
TP Load
Reduction %
With-Controls
TP Reduction %
(compared to
“no controls”
total load)
Current Code Scenario #1 Scenario #2
Projected
Analyzed
Area
Projected “With
Controls” TP
Load Reduction
%
Is TP Load
Reduction
Target Met
Projected
Analyzed
Area
Projected “With
Controls” TP
Load Reduction
%
Is TP Load
Reduction
Target Met
Projected
Analyzed
Area
Projected “With
Controls” TP
Load Reduction
%
Is TP Load
Reduction
Target Met (acres) (acres) (acres)
Sawyer Creek 2,707 85.6% 20.2% 24 2,834 28.6% No 2,834 29.4% No 2,834 30.1% No
Lake Butte
des Morts 2,137 85.6% 18.3% 30 2,296 31.5% No 2,296 32.7% No 2,296 33.9% No
Fox River 3,452 85.6% 28.6% 2 3,462 29.1% No 3,462 29.1% No 3,462 29.2% No
Lake
Winnebago 7,041 85.6% 24.8% 23 7,165 28.2% No 7,165 28.5% No 7,165 28.9% No
Neenah
Slough 35 40.5% 0.0% 2 45 38.5% No 45 40.9% Yes 45 43.3% Yes
Total 15,371 80 17,771 17,771 17,771
Note: Analysis projected the future annual growth rate and calculated the estimated increased pollutant loads associated with new development. Pollutant reductions associated with the various Municipal Code Scenarios were then applied to the
loads from new development areas. These pollutant loads were added to the “no controls” and “with controls” pollutant loads calculated in this analysis and the change in Citywide pollution reduction was calculated. Details regarding the steps
completed, assumptions and inputs are provided in Section 4.8.2 and Appendix J.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-26
Oshkosh SWMP Final
4.8.3 Site Specific Analysis
The Municipal Code scenarios considered above would implement numeric TP reduction
requirements under the current code. Under the scenarios considered, an increased level of both
TSS and TP control would be required. These increased requirements would result in increased
pollution reduction to step towards compliance with the TMDLs as described above. However, there
would also be an impact to developments that would need to comply with the modified code. To
evaluate the potential impact of Municipal Code changes, some past development sites were
considered. Past sites were selected to represent redevelopment and new development examples
and the SMPs installed as part of those projects were evaluated and modified in WinSLAMM to
understand if the various code scenarios could be met.
4.8.3.1 Redevelopment Site
As part of this analysis two recent City projects were considered that both fit into the category of
redevelopment. The first site was the Ceape/Otter Parking lot reconstruction project (construction
occurred in two phases across 2018 and 2019). This project was the reconstruction of an existing
parking lot including removal of the existing pavement, reconfiguration, and installation of new
pavement. This reconstruction would be similar to many private projects where parking lots are
reconstructed. To meet the Municipal Code requirements, porous pavement was installed.
To evaluate the site, a WinSLAMM model was built to replicate the model created at the time of the
site design. The model was built based on input files included in the approved SWMP for the project.
The model was then revised to meet current WDNR guidance for porous pavement, including to set
the TSS reduction associated with runoff that flows through the porous pavement underdrain to
65 percent (a corresponding TP reduction of 35 percent is applied). The WinSLAMM model was
executed, and the results were evaluated. The site achieves a TSS reduction of 63.2 percent and a
TP reduction of 34.7 percent. This exceeds the current Municipal Code requirements for both TSS
and TP, and the TSS requirements under Scenarios #1 and #2. However, the TP requirement is not
met for either scenario.
The potential to modify the site was considered to achieve the TP requirements of the two scenarios.
Based on the type of SMP utilized for the site (porous pavement), there are limited modifications that
can be made to achieve compliance in either scenario. The considerations for the site are described
below.
• Nearly the entire site is treated by porous pavement. Based on the layout and topography of the
site, the vast majority of runoff was directed to the porous pavement areas. It is not practical to
divert additional area to the current porous pavement or to add new porous pavement areas.
Under different sites, it may be possible to increase the treatment levels by treating more of the
project area.
• Under WDNR guidance, porous pavement is credited with 65-percent TSS reduction and
35-percent TP reduction for water that drains through the pavement and out of the underdrain.
Runoff that is infiltrated into the ground is credited with 100-percent reductions for both
pollutants. If other criteria are met for the pavement design (particularly the infiltration rate
needs to be maintained above 10-inches/hour) this reduction continues to be met. If the criteria
is not met, the pavement is considered to be non-functional and needs to be reconstructed to
restore the infiltration capability. Thus, increasing the size of the pavement will not increase the
TSS or TP reduction achieved.
• Related to this factor is the ability to infiltrate runoff into the native soil below the pavement.
Infiltrated water achieves a 100-percent reduction in pollutants and can assist in meeting higher
required levels of TP control. As described previously in the report, the majority of areas within
City of Oshkosh Stormwater Quality Management Plan Section 4
4-27
Oshkosh SWMP Final
the City are comprised of clay soils with low infiltration rates. The infiltration rate identified for
part of the porous pavement system in the northern part of the parking lot is 0.04 inches/hour,
which correlates with silty clay loam soils. The southern part of the parking lot has an infiltration
rate of 0.00 inches/hour as an impermeable liner is included due to contaminated soil. Another
limiting factor to infiltration in this area is tailwater from the Fox River. The site is only a few feet
above the typical summer water level in the river and portions of the storm sewer system
draining the site are submerged. The proximity to the water level will limit the ability for
infiltration to occur. It can also be noted that conducting infiltration rate testing could reveal
higher infiltration rates and result in increased reduction.
• Under different soils / groundwater conditions, a higher level of pollution control could be met. A
hypothetical analysis of infiltration rates was completed to determine what soil conditions would
be needed to meet the different code scenarios. This analysis was conducted to consider
whether the porous pavement could be utilized to meet the redevelopment requirements in the
code scenarios. The analysis increased the infiltration rate to various rates and is summarized in
Table 4-15 below.
Table 4-15. Ceape/Otter Parking Lot Alternative Evaluation & Ordinance Scenario Compliance Summary
Current Design Alternative 1 Alternative 2 Alternative 3
TSS Reduction 63.2% 64.1% 64.8% 65.7%
TP Reduction 34.7% 36.4% 37.8% 39.4%
Is Municipal Code Met?
Current Code
TSS = 40% / TP = 27%
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
Scenario #1
TSS = 58.4% / TP = 39.4%
TSS = Yes
TP = No
TSS = Yes
TP = No
TSS = Yes
TP = No
TSS = Yes
TP = Yes
Scenario #2
TSS = 52% / TP = 35%
TSS = Yes
TP = No
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
Alternative 1 = Changed native soil infiltration rate to equal 0.04 inches/hour for all porous pavement areas. Infiltration
rate equal to WDNR standard for silty clay loam or sandy clay soil.
Alternative 2 = Changed native soil infiltration rate to equal 0.07 inches/hour for all porous pavement areas. Infiltration
rate equal to WDNR standard for clay soil.
Alternative 3 = Changed native soil infiltration rate to equal 0.11 inches/hour for all porous pavement areas. Infiltration
rate equal to WDNR standard for sandy clay loam soil.
The second site considered was the City’s Field Operations Facility reconstruction. This project was a
complete reconstruction of an institutional/industrial facility. The Field Operations Facility houses
much of the City’s public works equipment and includes building area, parking areas, and outside
storage areas. The project was entirely a redevelopment project (it actually resulted in a decrease in
the impervious area at the site). For SMPs the site includes two underground wet detention basins,
four 2-foot-by-3-foot inlets with sumps, two 4-foot diameter catch basins with sumps, a grass swale,
and four biofilters.
A WinSLAMM model previously built for the site by BC was utilized as the starting point for the
analysis. The model was built to support a Stormwater Utility credit application for the site. This
model was revised to remove untreated building and landscaped areas on the site. Municipal Code
requirements apply to parking lot and driveway redevelopment areas. Thus, building and landscaping
areas can be excluded if they do not drain to a SMP. The analysis previously only accounted for TSS.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-28
Oshkosh SWMP Final
The model was updated to also include TP. Under this scenario a TSS reduction of 57.8-percent and
TP reduction of 23.1 percent is achieved. This meets the TSS requirements of the current Municipal
Code, and also Scenario #2. However, the TSS reduction for Scenario #1 is not met and the
TP reductions are not met for any scenario. Potential site changes that could be made to achieve the
requirements were considered. Steps taken in the analysis are described below.
• The existing biofilters include an engineered soil mixture that has a six-inch top layer of
85-percent sand and 15-percent compost. Currently WDNR guidance does not allow
TP reduction credit from engineered soil that includes compost. A 35-percent TP reduction can
be achieved if 100-percent sand is used. Alternative #1 assumed that the biofilters were
converted to use 100-percent sand. Beyond this conversion there are no additional
modifications that can be made to increase the pollutant removal of the biofilters. The detailed
model output shows that all of the runoff drains through the underdrain. The biofilters are also
lined and infiltration is not allowed due to contaminated soils. This is a similar situation to the
porous pavement discussion previously for the Ceape/Otter parking lot. An evaluation of
modifying the native soil infiltration rate was not considered for this site as other treatment
modification options exist. This change results in meeting the TP requirements for the current
code and Scenario #2; however, the TSS and TP requirements for Scenario #1 remain unmet.
• The inlet and catch basins with sumps at the site could be increased in size to raise the level of
TSS and TP control provided. Alternatives 2 through 4 considered increasing the size of the inlets
and catch basins. By increasing the size of the catch basins, the TSS and TP reductions
requirements can be met.
• The size of the underground storage could also be increased in size to increase the pollution
control. Alternative 5 considered doubling the size of the underground storage. In this alternative
all TSS reduction requirements would be met; however, the TP reduction for Scenario #1 would
not be met. There is limited benefit from increasing the size of the underground storage further.
Removing additional levels of TP from the drainage area to the underground storage is difficult.
The results of this analysis are summarized for the Field Operations Facility site in Table 4-16.
Table 4-16. Field Operations Facility Alternative Evaluation & Ordinance Scenario Compliance Summary
Current Design Alternative 1 Alternative 2 Alternative 3 Alternative 4 Alternative 5
TSS Reduction 56.8% 56.8% 57.2% 60.5% 61.2% 59.4%
TP Reduction 23.1% 36.1% 36.6% 39.3% 39.9% 38.3%
Is Municipal Code Met?
Current Code
TSS = 40% / TP = 27%
TSS = Yes
TP = No
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
Scenario #1
TSS = 58.4% / TP = 39.4%
TSS = No
TP = No
TSS = No
TP = No
TSS = No
TP = No
TSS = Yes
TP = No
TSS = Yes
TP = Yes
TSS = Yes
TP = No
Scenario #2
TSS = 52% / TP = 35%
TSS = Yes
TP = No
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
Alternative 1 = Conversion of biofilters to sand filter to allow for TP reduction credit.
Alternative 2 = same as Alternative 1, plus convert 2’x3’ inlets with sumps to 4’ diameter catch basins with sumps
Alternative 3 = same as Alternative 1, plus convert inlets and catch basins to 8’ diameter catch basins with sumps
Alternative 4 = same as Alternative 1, plus convert inlets and catch basins to 8’x8’ square catch basins with sumps
Alternative 5 = same as Alternative 1, plus convert 2’x3’ inlet with sumps to 4’ diameter catch basins with sumps, plus double size of
underground wet detention
City of Oshkosh Stormwater Quality Management Plan Section 4
4-29
Oshkosh SWMP Final
For both sites, alternative practices were conceptually considered. Utilizing a proprietary storm water
filtration device would not be feasible at either of these sites due to the lack of topographic relief and
the proximity to the Fox River. Proprietary filters include a minimum of 18 inches of head to function,
which is not available at either site. Additionally, they need to be located above tailwater to allow the
filters to dry out between storm events and continue to function. This is not feasible at both sites.
The use of these products is feasible in other areas of Oshkosh, and proprietary filters have been
incorporated into private redevelopment sites. These products can achieve TP reductions in excess
of a 50-percent.
The use of a wet detention basin would also not be feasible. At the Ceape/Otter Parking lot, there is
not sufficient space to include a wet detention basin within the site. The Field Operations Facility is a
larger site; however, a wet detention basin would not fit at this site as the operational requirements
of the site do not allow space to be allocated for a wet detention basin (hence, why an underground
wet detention basin was used in the site design).
The analysis of both of these sites shows that increased pollutant reduction can be achieved.
However, increased reductions become increasingly difficult. This is particularly true for meeting
TP reduction requirements. Two SMPs routinely used in redevelopment projects (porous pavement
and biofilters) can only achieve a maximum of a 35-percent TP reduction. (Note that this assumes
that a sand filter is used in lieu of a biofilter.) Reaching levels above 35-percent becomes
increasingly difficult when site constraints are considered.
The use of emerging technologies such as prairie treatment systems, using iron filings as part of an
enhanced sand filter, or incorporating iron filings or slag into porous pavement systems may allow for
higher TP removals. Additionally, as mentioned previously, alternative engineered soil mixtures may
be developed. However, guidance for these technologies has not been provided by the WDNR and
they are not incorporated into WinSLAMM.
4.8.3.2 New Development
To consider potential impacts on new development projects, a multi-family residential site was
selected for the analysis. The City has seen a number of multi-family new development projects
recently. It was felt that selecting one of these projects would be representative and informative. For
the analysis, a site named “The Wit” was utilized. The site is an 18.5-acre site with 12 apartment
buildings, garages, and a clubhouse building. A wet detention basin was used to meet pollution
reduction requirements for the site, and also peak flow control requirements. A WinSLAMM model
was built for the site based on the WinSLAMM input files included in the approved SWMP for the site.
No updates to the WinSLAMM model for recent WDNR guidance or WinSLAMM model changes was
required. Under the current site design, a TSS reduction of 85.5-percent, and a TP reduction of 62.7-
percent are achieved. This exceeds the current code requirements, and also meets TSS and TP
reductions for Scenario #1. Under Scenario #2, the site would meet TP reductions but not TSS.
The level of pollution reduction achieved is likely increased above the minimum requirements
because of the City’s peak flow reduction requirements for new development. New developments
must reduce the 100-year post development peak flow rate to less than the 10-year pre-
development peak flow rate. It was observed in reviewing the recent new developments that a
number of them achieve TSS reductions well in excess of the 80-percent requirement. The average
reduction from recent new development sites was 84-percent.
To evaluate the potential impact of ordinance changes, the sizing of the wet detention basin was
increased as needed to meet code Scenario #2, the stage-area relationship of the wet pond was
increased incrementally until a TSS reduction of 90-percent was achieved. A 55-percent increase
was needed to reach this requirement.
City of Oshkosh Stormwater Quality Management Plan Section 4
4-30
Oshkosh SWMP Final
An additional evaluation was also conducted to evaluate the wet detention basin size needed to
more closely meet the current code requirements. The wet detention basin stage-area was
decreased incrementally until a TSS reduction of closer to 80-percent was achieved. A 30-percent
reduction in the pond size resulted in an 80.8-percent TSS reduction. It should be noted that the
reduced detention basin size would likely result in the peak discharge reduction requirements not
being met for the site. Table 4-17 shows a summary of the analysis.
Table 4-17. The Wit New Development Alternative Evaluation & Ordinance Scenario
Compliance Summary
Current Design Alternative 1 Alternative 2
TSS Reduction 85.5% 90.2% 80.8%
TP Reduction 62.7% 66.4% 59.0%
Is Municipal Code Met?
Current Code
TSS = 80% / TP = 54%
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
Scenario #1
TSS = 85.5% / TP = 57.4%
TSS = Yes
TP = Yes
TSS = Yes
TP = Yes
TSS = No
TP = Yes
Scenario #2
TSS = 90% / TP = 61%
TSS = No
TP = Yes
TSS = Yes
TP = Yes
TSS = No
TP = No
Alternative 1 = 55-percent increase in stage-area relationship for wet detention basin
Alternative 2 = 30-percent decrease in stage-area relationship for wet detention basin
The use of SMPs, other than a wet detention basin, would likely not be feasible as part of new
developments under modified Municipal Code scenarios. By including a TP reduction requirement
commensurate with TSS reduction required in the current code, other SMPs (based on currently
available technology) are not able to meet the TP requirements. As described previously,
TP reductions in excess of 35 percent can be difficult to achieve. The only practices that can feasibly
achieve higher reductions are proprietary filters, wet detention basins, or new technologies that do
not currently have WDNR guidance associated with them.
4.9 Considerations for Other Potential SMPs
One requirement of the MS4 permit (Section C.4.3 a.) is that the City evaluate all SMPs for which a
WDNR Technical Standard exists. Within this SWMP and past Citywide SWMPs, wet ponds (Technical
Standard 1001), biofilters (Technical Standard 1004), rain gardens (Technical Standard 1009), and
vegetated swales (Technical Standard 1005) were evaluated in detail. The use of infiltration basins
(Technical Standard 1003) and infiltration trenches (Technical Standard 1007) were eliminated from
consideration as the soils found within the City generally do not support infiltration. This is evidenced
by soils data shown in Section 2.6. Additionally, as part of the implementation of projects including
regional SMPs, non-regional SMPs associated with parking lots reconstruction projects, and road
reconstruction, the City routinely conducts geotechnical investigations. These investigations have not
shown subsurface conditions (soils and groundwater level) suitable for infiltration. On a site-by-site
basis, there may be an opportunity for constructing infiltration practices; however, these practices
are not anticipated to be feasible from a planning level perspective.
Catch basins with sumps were incorporated into this SWMP and are utilized by the City as part of
street reconstruction projects. These are similar to proprietary storm water sedimentation devices
City of Oshkosh Stormwater Quality Management Plan Section 4
4-31
Oshkosh SWMP Final
(Technical Standard 1010). The use of catch basins provides a limited incremental benefit in TSS
and TP reductions on a Citywide basis when considered in conjunction with the City’s street sweeping
program. The City plans to continue constructing catch basins with sumps as part of street
reconstruction projects as they trap coarse sediment and prevent it from settling in downstream
storm sewers, SMPs, or waterbodies. Additionally, as part of the 9th Avenue Reconstruction
Stormwater Evaluation, the use of catch basins with sumps of varying sizes were considered. It was
found that using larger catch basins can potentially increase pollution reduction; however, there are
construction feasibility constraints with using larger structures. Specifically, there are additional
conflicts with other City and private utilities. On a case-by-case basis, the use of larger catch basins
may be feasible; however, they still will not produce pollutant reduction levels required by the TMDL.
In the 9th Avenue study, if 4-foot diameter catch basins with sumps could be implemented, a TSS
reduction of 30-percent was estimated. The associated TP reduction would have been less (TP was
not evaluated as part of the study). This is far below the TP reduction level required and, thus, catch
basins are not a feasible SMP for achieving TMDL compliance.
Non-regional SMPs were incorporated into this SWMP and these non-regional SMPs include other
practices including proprietary storm water filtration devices (Technical Standard 1010) and
permeable pavements (Technical Standard 1008). Permeable pavement was discussed above as
part of the site-specific redevelopment site analysis. This SMP has been utilized as part of various
private developments in Oshkosh and by the City as part of their parking lot reconstruction program.
The City has found this practice to be a cost-effective practice that is well suited for incorporation
into parking lot reconstructions. However, as described in the above section, there are limitations to
the pollution control achieved with a maximum of 65-percent TSS and 35-percent TP reductions,
unless infiltration occurs. Thus, this practice is also not feasible for achieving TMDL compliance. It is
a practice that can be incorporated into redevelopment sites to meet Municipal Code requirements.
Proprietary storm water filtration devices have been incorporated into several private development
sites to assist in meeting pollution reduction requirements for the site. These developments have
identified them as cost-effective practices to meet their requirements. However, as described
previously in this report, they must be located outside of tailwater conditions, and they require head
to be available in the system. Both of these issues occur frequently in the City. Additionally, an
evaluation of the use of these devices by the City identified them as not being cost-effective,
particularly when maintenance costs are required. These devices were also evaluated in the 9th
Avenue Reconstruction Stormwater Study. As part of this study the devices would have removed 1.2
tons of TSS annually. The construction cost was estimated to be $300,000 and the annual
maintenance cost was estimated at $18,000. This would equate to an annualized cost of about
$32,000 (based on a 35-year lifespan of the filter system with annual replacement of filter
cartridges). This cost is higher than other SMPs considered as part of this study. Again, this is a
practice that may be suitable for certain situations and conditions; however, they are not a feasible
practice for widespread use to meet the TMDL requirements.
5-1
Oshkosh SWMP Final
Section 5
Miscellaneous MS4 Permit Items
As part of the Citywide study as outlined in the WDNR grant, the City reviewed various components of
their stormwater management program to verify compliance with their MS4 permit. The review of
these items is documented in this section.
5.1 Ordinance Review
City of Oshkosh Municipal Code Chapter 14 was reviewed as compared to MS4 permit requirements
for construction site pollutant control (permit section 2.4.1) and post-construction stormwater
management (permit section 2.5.1). The Municipal Code was previously revised in 2014 to comply
with the prior MS4 permit.
5.1.1 Construction Site Pollutant Control
MS4 permit section 2.4.1 was reviewed and the requirements were compared to Municipal Code
Chapter 14, in particular, Article III: Construction Site Erosion Control. The review of the code verified
that the MS4 permit requirements were met. It should be noted that the erosion and sediment
control plan requirements in NR 216.46, as referenced in permit section 2.4.1.d., are not explicitly
addressed within the Municipal Code; however, the City’s Site Plan Review Checklist includes
requirements meeting NR 216.46.
5.1.2 Post-Construction Stormwater Management
MS4 permit section 2.5.1 was reviewed and the requirements were compared to Municipal Code
Chapter 14; in particular, Article IV: Post-Construction Storm Water Management. The review of the
code verified that the MS4 permit requirements were met.
5.2 MS4 Map Review
An additional component of the SWMP update was to review the MS4 map for compliance with the
requirements under Section 2.8 of the City’s MS4 permit. The MS4 map, dated February 18, 2022,
that was submitted as part of the 2021 Annual Report (submitted to WDNR in March, 2022) was
obtained and reviewed in comparison to the requirements of Section 2.8 (items 2.8.1 through 2.8.8).
The map largely meets the requirements of Section 2.8; however, BC identified several modifications
that should be made to the MS4 map to fully comply with the permit.
• To address Section 2.8.1, BC suggests the following revisions.
− Adding the symbol for lakes/large rivers to the legend (a light blue polygon) and increasing
the size of the text identifying Lake Butte Des Morts, Fox River, and Lake Winnebago.
− The classification of receiving waters should be identified, it is suggested to add a footnote
to the legend with the classification.
− Lake Butte Des Morts and Lake Winnebago should be identified as impaired waters. It is
suggested to complete this with a footnote in the legend.
− The map should identify the locations of swales that are part of the City’s MS4, similar to
how storm sewers are identified.
City of Oshkosh Stormwater Quality Management Plan Section 5
5-2
Oshkosh SWMP Final
• To address Section 2.8.4, BC suggests that the map distinguish between WPDES permits for
construction sites and industrial facilities. The location of WPDES permits are identified on the
map. From the map, it appears two locations correspond with WPDES construction site permits
that were active at the time the map was updated. The map should also identify industrial permit
holders within the City.
• To address Section 2.8.5, public and private stormwater management practices identified on the
map should be updated to be consistent with the practices incorporated in this study. The labels
identifying practices on the map should also be reviewed and adjusted appropriately. Many of
them are offset from the location of the practice.
• To address Section 2.8.7, BC suggests the following revisions.
− Within the Field Operations Facility, the central garage, salt storage, and yard waste areas
are identified. It appears the locations of the salt storage and yard waste area should be
revised to reflect their locations more accurately within the facility.
− Snow storage areas are not identified on the map. These areas should be added as public
works facilities.
6-1
Oshkosh SWMP Final
Section 6
Implementation Plan
Under the City’s MS4 General Permit, Section 1.5 describes the requirements for compliance with
“approved TMDLs”. For the City of Oshkosh, this includes both the Lower Fox River TMDL and the
Upper Fox/Wolf River TMDL. One of the permit requirements is the development of an
implementation plan if the stormwater pollution analysis shows that the current pollution control
level is not meeting the pollutant reduction requirements for each reachshed in the MS4. The permit
states that the implementation plan schedule may extend beyond the expiration date of the current
permit, and no ultimate implementation deadline is specified. The analysis conducted in Section 3 of
this report concludes that the City’s existing management practices do not fully achieve the TSS or
TP reduction targets for all reachsheds and, therefore, the City must develop an implementation
plan.
This report has evaluated multiple potential actions that the City could take and stormwater
management practices that the City could implement to move towards future compliance with the
TMDL reduction targets as outlined in Section 4. The WDNR requires that MS4 permittees show
continued progress towards achieving the pollution reduction targets. This section discusses
components that have been selected by the City for implementation.
6.1 Implementation Plan Components
As previously stated, the current MS4 Permit does not require the City to set a firm deadline for when
the pollution reduction targets will be met. The permit language states that the City must “make
progress toward achieving compliance”. This plan provides a clear approach to “make progress
toward achieving compliance”. This plan provides an initial schedule for implementation of SMPs
and the corresponding impact on pollutant loadings to the various reachsheds and is contained in
Appendix K. Where applicable, the impacted area associated with a specific practice being
implemented is noted. The schedule was developed to be achievable within the technologies
currently available and with an eye on cost effectiveness of practices and approaches overall.
General details of the implementation plan components are described in the following sections.
One requirement from the MS4 permit (Section C.4.3 b.) is that the “schedule should aim to achieve,
to the maximum extent practicable, a level of reduction that achieves at least 20% of the remaining
reduction needed beyond baseline to achieve full compliance in TSS and a level of reduction that
achieves at least 10% of the remaining reduction needed beyond baseline to achieve full compliance
in TP over the next permit term.” The permit further identifies that these reductions can occur across
the entire MS4 and are not specific to each reachshed. The City’s level of TSS and TP reduction from
existing SMPs currently meets this requirement. A summary of the current level of control and
compliance with the incremental TSS and TP reduction requirements for the next permit term (2024
to 2029) is provided in Table K-1 in Appendix K.
To assist in comparing SMPs and developing the implementation plan, a table comparing the
potential SMPs from this study was prepared (included as Table K-2 in Appendix K). This table
provided metrics to compare the performance and cost-effectiveness of SMPs. The table was
reviewed by the City and discussed as part of the implementation plan development process.
Ultimately, the projects were prioritized and scheduled. Notes are included in the table summarizing
the selection process.
City of Oshkosh Stormwater Quality Management Plan Section 6
6-2
Oshkosh SWMP Final
Additionally, the implementation plan includes items that are not specific structural SMPs. These
projects are items that are either already part of the City’s stormwater management program that
work towards addressing TMDL goals, or were items specifically identified as part of this planning
process. These various projects were discussed with the City and organized to fit into the
implementation plan in the next eight years. This horizon is consistent with when the next Citywide
SWMP update is scheduled to occur. Completing these projects in that timeline will assist in the next
Citywide SWMP update. Table K-3 in Appendix K was prepared to summarize the results of the
project planning with the City. Many of these items are already part of City projects and including
them as part of this implementation plan helps to show the various planning efforts the City is
undertaking to meet TMDL requirements.
Based on Tables K-2 and K-3, an implementation plan was then developed for each reachshed as
Tables K-4 through K-8 in Appendix K. The plans list the initial projects identified and the scheduled
dates for implementation. Remaining SMPs are identified for potential future implementation
without a scheduled date. In addition, the non-measurable items are included in the implementation
plan.
It should be noted that reachshed implementation plans will not result in compliance with
TP reduction requirements for the Upper Fox/Wolf River TMDL. The TP reduction requirement of 85.6
percent are in excess of the reductions that are feasible with current technologies. This plan lays out
steps that considered current technologies and how feasible it would be to implement these
projects. The implementation plan identifies the initial six highest priority structural SMPs and
stretches over six MS4 permit terms (30 years). It is believed that this detailed planning duration
represents the limit at which planning can reasonably be completed. The SMPs that are not included
in the initial planning remain to be considered for future implementation. Further, it is expected that
over the course of this time, the available technology will change and this SWMP will be updated to
account for changes to both technology and physical changes within the City. As the SWMP is
updated, the implementation schedule will be reviewed and updated based on any new information
available.
Also, project opportunities and challenges are expected to arise within the implementation plan. This
may result in the implementation plan being revised to meet the opportunities or challenges. It is
anticipated that the plan will be reviewed/revised as part of the City’s annual Capital Improvement
Program (CIP) update.
6.1.1 Existing Non-Regional SMPs – Additional Research and Action
As described in Section 4.1 of this report, there are non-regional SMPs missing Operation &
Maintenance Agreements, or missing data, that prevents some non-regional SMPs from being
incorporated into the City pollutant load reductions towards TMDL compliance. As an action under
the implementation plan, the City will further research these existing SMPs in order to collect the
data necessary to account for them. As research indicates, additional action towards obtaining
Operation & Maintenance Agreements will be taken to the extent practicable. As necessary,
additional analysis to evaluate the pollution reduction of sites will be completed.
6.1.2 Leaf Management
There are small areas within the Sawyer Creek and Fox River reachsheds that meet the criteria for
eligibility under the WDNR’s leaf management guidance. To obtain credit, minor operational changes
would need to be made by the City. However, given the limited impact in pollution reduction credit
these areas would provide, the City will continue to utilize the current leaf collection program. The
City has scheduled a more detailed analysis in 2027 to evaluate if there may be additional eligible
City of Oshkosh Stormwater Quality Management Plan Section 6
6-3
Oshkosh SWMP Final
areas by investigating additional and/or updated information and considering any additional
guidance/studies.
6.1.3 Regional Stormwater Management Practices
The City currently has many regional SMPs located throughout the various reachsheds that provide
reliable and proven stormwater treatment. The City is continuing to provide routine maintenance to
allow these practices to continue to function appropriately.
This plan evaluated 14 potential locations in detail for future regional SMPs and the implementation
plan has scheduled six practices for installation. Projects are generally scheduled for development
over a 5-year period to allow for land acquisition, environmental investigations, engineering design,
and construction. Projects are scheduled sequentially through 2054. The remaining projects are
identified for future implementation and will be scheduled as part of future planning efforts.
6.1.4 Enhanced Settling for Phosphorus Removal
As part of this study, the City has considered the use of coagulant treatment of stormwater runoff to
provide enhanced settling for pollutant removal. This study considered the potential to retrofit
existing regional SMPs to provide a greater level of pollutant reduction. An initial evaluation of each
regional SMP was completed, and then four regional SMPs were evaluated at a planning level to
determine the potential feasibility of a retrofit for enhanced settling.
At this time, there remains uncertainty regarding the use of this practice in Wisconsin, including
requirements associated with using the practice and associated costs. It appears that the WDNR
may be planning to develop technical guidance for the use of coagulants in stormwater that could
reduce some of the uncertainty with implementing this technology. Thus, the implementation plan
includes an additional study of enhanced settling for phosphorus removal to be conducted after
additional guidance becomes available. This study is tentatively scheduled for 2028 to 2029.
Currently, the implementation plan includes the first wet detention pond augmentation project
starting in 2039. It is possible that the establishment of WDNR guidance for this practice, and the
results of the preliminary engineering study, may result in a recommendation to adjust the schedule
and incorporate enhanced settling differently. These possibilities will be considered as part of future
planning efforts and schedule updates.
6.1.5 Municipal Code Modifications
This study included an evaluation of the impact of modifying the City’s current post-construction
stormwater management code to incorporate increased pollution (TSS and TP) reduction
requirements (note that maximum extent practicable can still be requested) that will positively
impact TMDL reachsheds for new development and redevelopment.
The evaluation of Municipal Code modifications showed that changes would result in a step towards
reaching TMDL requirements (a higher reduction from current code requirements). However, the
shortcomings of available technology that can meet the TP reduction requirements from the Upper
Fox/Wolf Rivers TMDL is a limitation. Based on the analysis conducted as part of this project, and
discussions with City Staff, the implementation plan includes additional evaluation of potential
Municipal Code modifications. This would include outreach to other stakeholders and is scheduled
for 2023-2024.
An initial concept for code modifications would be to include TMDL specific requirements for TSS,
such as, increasing the TSS reduction requirement for redevelopment in the Sawyer Creek
reachshed to 58.4 percent. A TP reduction requirement would likely also be included in the
Municipal Code and would be based on further consideration of the site specific analysis conducted
City of Oshkosh Stormwater Quality Management Plan Section 6
6-4
Oshkosh SWMP Final
as part of this study and future evaluations. Currently small developments less than 20,000 square
feet are not typically subject to pollution control requirements, but they must “collect and convey”
stormwater from their site. Another option for Municipal Code modifications is to require these small
developments to install catch basins with sumps as part of the conveyance system.
6.1.6 Incorporation of Non-Regional SMPs from Future Development
As described above, the study considered the potential for Municipal Code modification to result in
increased pollution reduction from future development (new development and redevelopment). The
implementation plan includes estimated pollutant reductions that would be associated with
development projects. The pollutant reductions are estimated based on the prior rate of
development and projected pollutant reductions that would be associated with the development.
This study considered a 30-year planning cycle for development and the implementation plan
incorporates these theoretical improvements over this period. The actual reductions associated with
redevelopment and new development is subject to change based on actual development that
occurs. It should be noted that new development also results in a modification to the “no controls”
pollutant loads. An estimate for this modification was incorporated; however, it is an additional
variable that will change as development occurs. The impacts of redevelopment and new
development will be reviewed and summarized as part of future Citywide SWMP updates. For
projections in the implementation plan, the reductions associated with development are assumed to
be based on current Municipal Code requirements.
6.1.7 Rain Gardens & Biofilters
In the prior 2014 Citywide SWMP, biofilters and rain gardens were investigated as ways to treat more
dispersed areas when regional facilities could not be implemented. This analysis was updated as
part of this study. While the evaluation was conducted on a high level, it generally resulted in a
higher cost per ton of TSS or pound of TP that regional SMPs. There are some individual regional
SMPs that result in higher costs per ton of TSS or pound of TP; however, on average, rain gardens
and biofilters result in higher costs. Additionally, it is believed that the cost estimating methodology
for rain gardens and biofilters did not include all of the costs that would typically be seen on a project
if implemented as a stand-alone project by the City. These practices are challenging to implement
because they would largely be on private lands that require easement or acquisition, be impacted by
owner willingness and/or ability to give up the space and allow the project to proceed, topographic
and/or utility challenges that are unique to a given property/project, and the overriding concerns
over cost effectiveness and future maintenance. As part of the current implementation plan, rain
gardens and biofilters are identified as potential future implementation items. Additionally, it is
believed that they will continue to be used as non-regional SMPs as part of future new and re-
development activities as they can be more cost effectively incorporated into grading and
landscaping as part of a larger project.
6.1.8 Non-measurable Implementation Plan Components
In addition to various components of the implementation plan providing measurable progress
towards meeting the various TMDL reachshed goals, there are numerous other items identified in
the plan that do not provide direct quantifiable/measurable progress toward stormwater goals, but
are instrumental to a wholistic stormwater management program. The following list contains
implementation plan components that contribute toward improving stormwater quality and how they
are relevant to the implementation plan.
• Model development. Confirms existing SMP effectiveness and completes WinSLAMM model
library which will allow the City to incorporate additional City-owned non-regional SMPs into the
SWMP.
City of Oshkosh Stormwater Quality Management Plan Section 6
6-5
Oshkosh SWMP Final
• Stormwater utility billing database updates. Allows accurate billing charges and supports
revenue needed to implement the plan.
• Incorporation of SMPs into other City projects. There are several implementation plan items
associated with the review and evaluation to implement SMPs into other projects that are
completed by the City, including road construction projects, flood control projects, and other City
projects (such as parking lot reconstruction). These efforts work towards maximizing
opportunities to implement stormwater controls that would work toward TMDL goals.
• Screening of developments for added pollution reduction opportunities. This effort is focused
on creating opportunities to enhance the pollution removal achieved from non-regional SMPs.
• Plan updates. Allows the City to quantify progress towards meeting TMDL goals and evaluate
emerging technologies.
6.1.9 Implementation Plan Component Limitation and Opportunities
In development of this report and the resulting implementation plan, there are several qualifications
or limitations that should be understood and are listed in the following items:
• Identified implementation practice feasibility. The planning team made an effort to consider
potential hurdles and challenges to the implementation of the various practices evaluated. All
practices were discussed, evaluated, and identified for implementation with the support of City
staff and are believed to be implementable. Preliminary engineering will be needed to further
evaluate the specifics of each project, including detailed environmental evaluation and
permitting as needed.
• TSS and TP reduction estimates. Estimates are based on WinSLAMM modeling to the extent
possible. Final reductions achieved by a specific practice will be determined following design
and, ultimately, construction in some instances. There may be site constraints that cannot be
mitigated which lower the TSS and TP reductions achieved by a site or that results in a site being
deemed not feasible.
• Leaf Management reductions. Leaf management reductions on TP loads were calculated based
on an assessment of tree density and size (spacing) throughout the City, and current WDNR
guidance and limitations (such as applicability only to residential land use areas). Future
enhancements to the WDNR guidance and further understanding of tree cover/canopy may
allow expansion to current identified land use areas and/or include other land use areas to
increase TP credit. The leaf canopy in the City is currently expanding as the City has begun to
plant trees within the street terrace more routinely. Growth of trees and other potential impacts,
such as tree removal due to disease, will also contribute to change and evolution of this
practice. A leaf management analysis is identified for 2027 to investigate this practice further.
• Enhanced TP reductions through coagulant treatment. Estimates on performance and cost
associated with enhanced TP treatment as an augmented practice to wet detention ponds was
based on previous studies. The WDNR appears to be poised to develop technical guidance that
could reduce some of the unknowns with applying this technology. Furthermore, it is
recommended that additional research into this practice be conducted including pilot testing of
stormwater samples and coagulants and close coordination with City of Oshkosh Wastewater
Utility staff to evaluate any impact to WWTP operations and to further define both construction
and annual treatment and disposal costs.
• Financial. Cost estimates were developed from a number of sources including City provided
studies, labor costs, equipment costs, bid tables, and outside sources. An annual inflation value
of 3 percent was used to estimate the value of operation and maintenance activities to
determine present worth for cost efficiency comparisons, as well as to project the cost of
City of Oshkosh Stormwater Quality Management Plan Section 6
6-6
Oshkosh SWMP Final
identified construction implemented in future years. Market volatility and other factors can
impact the actual rate of inflation.
• Variability of development. The location and amount of development is difficult to predict and
variable in nature. The assumptions in this report are based on past development. However, if
future development (both new and re-development) occurs in a different pattern, the pollutant
reduction associated with that development will differ from the assumptions made in this plan.
Additionally, pollution reduction estimates are based on full compliance with the current or
future post-construction stormwater management ordinances, and does not include any
allowance for potential reduction in effectiveness due to approved maximum extent practicable
(MEP) that may be allowed to developers based on challenging site considerations, technological
limitations, or financial hardship/cost effectiveness reasons.
• Overlap of treatment practices. This plan accounts for existing SMPs that operate in series and
considered practices in-series as part of the alternatives analysis. However, it is not able to
consider how future development may occur. Development that occurs within areas tributary to
existing, or future, regional SMPs will have a more limited impact than development that occurs
in untreated areas.
6.2 Implementation Plan Results
The implementation plan provides details for the proposed activities as a result of this Citywide
SWMP Update. The plan results in meeting the Upper Fox/Wolf TMDL for TSS in the Sawyer Creek
reachshed. For the Upper Fox/Wolf TMDL reachsheds (Sawyer Creek, Fox River, Lake Butte des
Morts, and Lake Winnebago) the implementation plan does not meet, nor does the plan identify a
way to achieve, the 85.6 percent TP reduction goal. The implementation of practices from this plan
will step towards compliance and reduce the required TP reduction gap. The reduction target is
extremely aggressive and would require advanced treatment of stormwater runoff that is
technologically a challenge and can be extremely costly.
The implementation plan envisions the potential to meet Neenah Slough TMDL reduction targets
from the Lower Fox TMDL for TSS and TP as a result of new development.
City of Oshkosh Stormwater Quality Management Plan
A-1
Oshkosh SWMP Final.docx
Appendix A: Figures
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
o
x River
Lake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Sawyer CreekFigure 1-1TMDL ReachshedsCity of OshkoshStormwater Quality Management Plan
Legend
City Limits (July 2020)
Upper Fox/Wolf River TMDLReachsheds
Sawyer Creek
Lake Butte des Morts
Fox River - Lake Butte des Mortsto Lake Winnebago
Lake Winnebago
Lower Fox TMDL Reachsheds
Neenah Slough
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 1-1 TMDL Reachsheds.mxdCity limits are as of July 2020. Annexations afterthis date are not incorporated current study.These areas will be accounted for as part offuture SWMP updates.
0 8,0004,000
Feet
±
9/21/2022
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
o
x River
Lake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Sawyer CreekFigure 2-1TMDL Excluded AreasCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
TMDL Excluded Area
Agriculture
Quarry - Permitted Industrial
WisDOT Right-of-Way
Open Water
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 2-1 TMDL Excluded Areas_v2.mxd4/26/20220 8,0004,000
Feet
±
4/26/2022
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
o
x River
Lake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Sawyer CreekFigure 2-2Other MS4 Areas within Analyzed AreaCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Other MS4 Areas
UW Oshkosh
Winnebago Cty - Airport
Winnebago Cty - Highway
Winnebago Cty - Other
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 2-2 Other MS4 Areas.mxd4/26/20220 8,0004,000
Feet
±
4/26/2022
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
o
x River
Lake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Sawyer CreekFigure 2-3TMDL Land Use CategoryCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Land Use Category
Commercial
Industrial
Institutional
Parks and Open Space
Residential
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 2-3 Land Use Category.mxd4/26/20220 8,0004,000
Feet
±
4/26/2022
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
o
x River
Lake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Sawyer CreekFigure 2-4WinSLAMM Soil CategoryCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
WinSLAMM SoilCategory
Clay
Sand
Silt
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 2-4 Soils.mxd5/2/20220 8,0004,000
Feet
±
5/2/2022
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
o
x River
Lake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Sawyer CreekFigure 3-1Street Cleaning ZonesCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Street Cleaning Zones
Downtown (Once per Week)
Remainder of City (Once perweek for six weeks, then everyother week)Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 3-1 Street Cleaning Zones.mxd5/2/20220 8,0004,000
Feet
±
5/2/2022
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
o
x River
Lake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Sawyer CreekFigure 3-2Catch Basin Drainage AreasCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Catch Basin Drainage Areas
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 3-2 Catch Basins.mxd4/26/20220 8,0004,000
Feet
±
4/26/2022
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
o
x River
Lake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Sawyer CreekFigure 3-3City Grass Swale AreasCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Grass Swale DrainageArea by Group
Group 01
Group 02
Group 03
Group 04
Group 05
Group 06
Group 07
Group 08
Group 09
Group 10
Airport
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 3-3 City Swales.mxd5/3/20220 8,0004,000
Feet
±
5/3/2022
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
!!
!
!
!
!
!
!
!
!
!
!
F
o
x RiverSawyer CreekLake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Reg-7
Reg-6
Reg-4
Reg-8
Reg-5
Reg-9
Reg-2
Reg-3Reg-1
Reg-10
Reg-12
Reg-11
Figure 3-4Regional SMPsCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
!Regional SMP Locations
Regional SMP Trbutary Areas
9th & Washburn (Reg-10)
Armory (Reg-1)
City Hall (Reg-2)
E Nevada Ave (Reg-4)
Fair Acres/Murdock (Reg-5)
Fernau Watershed - North MainStreet Area (Reg-6)
Libbey-Nicolet (Reg-7)
Melvin Ave (Reg-8)
North High School Area (Reg-9)
Oakwood Road (Reg-11)
South Park (Reg-3)
Westhaven Club House (Reg-12)Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 3-4 Regional SMPs.mxd9/21/20220 5,0002,500
Feet
±
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(!(
!(!(
!(
!(!(
!(
!(
!(
!(
!(!(
!(!(
!(
!(
!(
!(
!(
!(
!(!(!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(!(
!(
8
3
6
9
1
4
7
5
2
48
57 68
69
14
51
17
18
21
29
33
58 59
45
56
35
19
72
39
25
2350
47
15
44
13
38
30
62
36
24
28
2720
11
43
40
55
54
31
65 70
3426
66
22
42
10
49
60 32
71 53
63
46 4161
12
37
52
16
67
64 64
F
o
x River
Lake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Sawyer CreekFigure 3-5Non-Regional SMPsCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
!(Non-Regional SMP Locations
Non-Regional SMP Parcels
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 3-5 Non-Regional SMPs.mxd9/15/20220 5,0002,500
Feet
±
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
o
x RiverSawyer CreekLake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Figure 3-6"No Controls" Total TP Load by WatershedCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Watershed Boundaries
"No Controls" TP Load (lbs/yr)
Less than 200
200 - 400
400 - 600
600 - 800
Greater than 800
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 3-6 No Controls TP Load by Watershed.mxd9/15/20220 5,0002,500
Feet
±
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
o
x RiverSawyer CreekLake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Figure 3-7"With Controls" Total TP Load by WatershedCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Watershed Boundaries
"With Controls" TP Load (lbs/yr)
Less than 200
200 - 400
400 - 600
600 - 800
Greater than 800
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 3-7 With Controls TP Load by Watershed.mxd9/15/20220 5,0002,500
Feet
±
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
o
x RiverSawyer CreekLake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Figure 3-8"No Controls" TP Load Per Acre by WatershedCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Watershed Boundaries
"No Controls" TP Load perAcre (lbs/ac/yr)
Less than 0.6
0.6 - 0.7
0.7 - 0.8
0.8 - 0.9
Greater than 0.9
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 3-8 No Controls TP Load Per Acre by Watershed.mxd9/15/20220 5,0002,500
Feet
±
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
o
x RiverSawyer CreekLake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Figure 3-9"With Controls" TP Load Per Acre by WatershedCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Watershed Boundaries
"With Controls" TP Load perAcre (lbs/ac/yr)
Less than 0.6
0.6 - 0.7
0.7 - 0.8
0.8 - 0.9
Greater than 0.9
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 3-9 With Controls TP Load Per Acre by Watershed.mxd9/15/20220 5,0002,500
Feet
±
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
!(
!(!(
!(!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(!(!(
!(
!(!(
!(!(
!(
!(
!(
!(!(
!(!(
!(
!(
!(
!(
!(
!(
!(!(!(!(
!(!(
!(
!(!(!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
Add-NR-89
Add-NR-5
Add-NR-7
Add-NR-8
Add-NR-2
Add-NR-6
Add-NR-9
Add-NR-3
Add-NR-1
Add-NR-4
Add-NR-88
Add-NR-33
Add-NR-56
Add-NR-30
Add-NR-74
Add-NR-63
Add-NR-53
Add-NR-14
Add-NR-64
Add-NR-40
Add-NR-22
Add-NR-39
Add-NR-34
Add-NR-11
Add-NR-36
Add-NR-21
Add-NR-57
Add-NR-23
Add-NR-35
Add-NR-85
Add-NR-15
Add-NR-77
Add-NR-32
Add-NR-13
Add-NR-25
Add-NR-38 Add-NR-55
Add-NR-10
Add-NR-41
Add-NR-60
Add-NR-44Add-NR-37
Add-NR-17Add-NR-18
Add-NR-78
Add-NR-82
Add-NR-31
Add-NR-79
Add-NR-68
Add-NR-72
Add-NR-76
Add-NR-75
Add-NR-45
Add-NR-83
Add-NR-84
Add-NR-86
Add-NR-49
Add-NR-50
Add-NR-47 Add-NR-48
Add-NR-20
Add-NR-46
Add-NR-16
Add-NR-81
Add-NR-80
Add-NR-24
Add-NR-65
Add-NR-29Add-NR-28
Add-NR-54
Add-NR-62
Add-NR-19
Add-NR-66
Add-NR-12
Add-NR-61
Add-NR-52
Add-NR-51
Add-NR-42
Add-NR-43
Add-NR-87
Add-NR-73
Add-NR-71
Add-NR-69
Add-NR-27Add-NR-26
Add-NR-59 Add-NR-58
F
o
x River
Lake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
91
44
21
45
45
76
45
Sawyer Creek44
Figure 4-1Non-Regional SMPs with O&M Agreements Not FoundCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
!(Non-Regional SMPs withoutO&M Agreements
Non-Regional SMPs withoutO&M Agreement Parcels
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 4-1 Added Non-Regional SMPs-NoOM.mxd9/21/20220 5,0002,500
Feet
±
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(!(
!(!(
!(
!(
!(!(
!(!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
F
o
x RiverSawyer CreekLake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Figure 4-2Previously Unidentified Non-Regional SMPsCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
!(Previously Unidentified Non-Regional SMPs
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 4-2 Post2004 Non-Regional SMPs.mxd7/15/20220 5,0002,500
Feet
±
Æ%
Æ%
Æ%
Æÿ
Æ%
F
o
x RiverSawyer CreekLake Butte des Morts
E
44
21
45
45
Figure 4-3Areas Eligible for Leaf Management CreditCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Eligible Areas
Untreated Areas
Treated by D/S SMP
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 4-3 Trees_EligibleAreas.mxd8/9/20220 2,0001,000
Feet
±
!(
!(
!(
!(
!(!(
!(
!(!(!(!(!(!(
!(!(!(
!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(
!(!(!(!(
!(!(!(!(!(!(!(!(!(
!(!(!(
!(!(!(!(
!(!(!(
!(!(!(
!(!(
!(!(!(!(
!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(
!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(
!(!(!(!(!(!(!(!(!(!(
!(!(!(
!(!(!(
!(!(!(!(!(!(!(!(
!(!(!(!(
!(!(!(!(!(
!(
!(
!(
!(
!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(
!(!(!(!(
!(
!(!(!(!(
!(
!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(
!(!(!(!(
!(
!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(
!(!(!(!(
!(!(!(!(
!(!(
!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(
!(!(
!(!(!(!(!(
!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(
!(
!(!(
!(!(!(
!(!(!(!(!(
!(
!(!(
!(!(!(!(!(!(
!(
!(!(!(!(
!(!(!(!(!(
!(!(!(
!(!(
!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(
!(!(!(
!(!(!(
!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(
!(
!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(
!(!(!(!(!(!(!(!(
!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(
!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(
!(!(
!(!(!(
!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(
!(!(!(!(!(
!(!(!(!(
!(!(!(!(
!(!(
!(
!(!(!(!(
!(!(!(!(
!(!(!(!(!(
!(
!(
!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(
!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(
!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(
!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(
!(
!(
!(!(
!(
!(!(!(!(!(
!(!(!(!(
!(!(!(!(!(
!(!(
!(!(!(!(
!(
!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(
!(!(
!(!(!(!(!(
!(!(!(
!(!(
!(!(
!(!(
!(!(!(!(!(!(!(!(
!(!(
!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(
!(!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(
!(!(!(!(
!(
!(!(!(!(!(!(!(!(
!(!(!(!(
!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(
!(!(
!(
!(!(!(!(!(!(
!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(
!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(
!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(
!(!(!(!(!(
!(!(
!(!(!(
!(!(!(!(!(!(!(!(
!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(
!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(
!(!(!(!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(
!(!(!(
!(!(
!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(
!(!(
!(!(
!(!(!(!(
!(
!(!(
!(
!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(
!(
!(!(!(!(!(!(
!(!(
!(!(!(!(!(
!(
!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(
!(!(!(!(
!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(
!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(
!(
!(
!(
!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(
!(!(!(!(!(!(!(!(
!(
!(
!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(
!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(
!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(
!(
!(!(!(!(!(!(!(
!(!(
!(
!(!(!(!(
!(
!(!(!(!(!(!(
!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(
!(!(!(
!(!(!(!(!(!(
!(
!(!(!(
!(
!(!(
!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(
!(!(!(!(
!(
!(
!(!(
!(
!(!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(!(
!(!(
!(
!(
!(
!(
!(
!(
!(!(
!(!(
!(!(!(!(
!(
!(
!(
!(!(!(!(!(!(
!(
!(!(
!(!(
!(
!(!(
!(
!(
!(!(
!(
!(
!(!(!(
!(!(
!(
!(
!(
!(
!(
!(
!(!(!(
!(!(
!(!(
!(!(!(
!(!(
!(!(
!(
!(
!(
!(
!(
!(!(!(!(!(!(
!(!(!(!(
!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(!(!(!(
!(
!(!(!(!(!(
!(!(
!(
!(
!(
!(!(
!(
!(
!(!(
!(
!(
!(!(
!(
!(!(
!(
!(
!(
!(!(!(!(!(
!(
!(!(
!(
!(!(
!(!(
!(
!(!(
!(!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(!(!(!(
!(
!(
!(
!(!(!(!(
!(
!(!(
!(!(
!(!(
!(
!(!(!(!(!(!(!(
!(!(
!(
!(!(
!(
!(!(!(!(!(
!(!(!(!(!(
!(!(!(
!(!(!(!(!(
!(
!(
!(
!(
!(
!(
!(!(!(
!(
!(
!(
!(!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(!(
!(
!(!(
!(!(
!(
!(
!(
!(!(
!(
!(!(
!(
!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(
!(
!(
!(!(
!(
!(!(!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(!(
!(
!(!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(!(
!(!(!(!(
!(!(!(!(!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(!(!(
!(
!(
!(!(!(!(!(
!(!(
!(
!(
!(
!(!(!(!(!(!(!(
!(!(
!(
!(!(!(!(
!(!(!(!(!(
!(
!(
!(!(
!(
!(
!(!(!(
!(
!(!(!(
!(
!(
!(
!(!(!(
!(
!(
!(!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(!(
!(!(
!(
!(
!(
!(!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(
!(!(
!(
!(!(!(
!(
!(
!(
!(
!(
!(!(
!(!(
!(
!(
!(
!(
!(
!(!(
!(
!(!(
!(!(
!(
!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(
!(
!(!(!(!(!(!(
!(
!(
!(
!(
!(!(!(
!(
!(
!(!(!(!(!(!(!(
!(
!(
!(
!(
!(
!(
!(
!(!(!(!(!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(!(
!(
!(
!(
!(!(
!(!(!(!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(
!(
!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(
!(
!(!(
!(
!(!(
!(!(
!(
!(
!(!(
!(
!(!(
!(
!(
!(
!(!(!(
!(
!(!(
!(!(
!(
!(
!(!(!(
!(
!(!(!(
!(!(!(!(!(
!(!(
!(!(!(!(!(!(!(
!(!(
!(!(!(!(
!(!(!(
!(
!(!(
!(
!(
!(
!(
!(
!(!(!(!(!(!(
!(
!(
!(
!(!(
!(!(!(
!(!(!(
!(!(!(!(!(!(!(!(
!(!(
!(
!(!(!(!(!(
!(!(!(
!(!(!(!(
!(
!(
!(
!(!(
!(
!(
!(!(!(
!(
!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(
!(!(
!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(!(!(!(
!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(
!(
!(
!(
!(!(!(!(
!(
!(
!(
!(!(!(!(!(
!(!(
!(!(!(!(
!(
!(!(!(!(
!(
!(!(
!(
!(
!(!(
!(
!(
!(
!(!(
!(!(!(
!(!(
!(
!(!(!(!(
!(!(!(
!(!(!(
!(!(
!(
!(
!(!(
!(!(!(!(
!(
!(!(
!(
!(
!(
!(
!(
!(!(!(!(!(
!(!(
!(
!(
!(
!(!(
!(
!(
!(!(
!(
!(
!(!(!(
!(!(
!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(
!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(
!(
!(!(
!(!(!(!(
!(
!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(
!(
!(!(!(
!(!(
!(
!(
!(!(!(!(
!(!(
!(!(!(!(!(!(!(
!(
!(!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(!(!(
!(!(!(
!(
!(!(!(
!(
!(
!(!(
!(!(
!(
!(!(
!(
!(
!(!(!(
!(
!(
!(
!(
!(
!(!(
!(!(!(!(
!(!(
!(
!(!(!(
!(!(
!(
!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(
!(!(!(
!(!(!(!(!(!(!(!(!(
!(
!(!(!(
!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(
!(
!(!(!(!(
!(!(
!(
!(
!(
!(!(!(
!(!(!(
!(!(
!(
!(
!(
!(!(!(!(!(
!(
!(
!(
!(
!(
!(
!(
!(!(!(!(
!(!(
!(!(
!(
!(!(
!(!(
!(!(!(!(!(
!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(
!(
!(!(
!(
!(!(
!(!(!(!(
!(!(!(!(!(!(!(!(
!(!(!(!(!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(!(!(
!(
!(
!(!(!(!(!(!(!(
!(!(
!(
!(!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(!(
!(!(
!(
!(
!(!(!(!(!(!(!(!(!(!(
!(
!(
!(
!(
!(!(!(
!(!(!(!(!(!(
!(
!(
!(
!(!(
!(!(!(!(
!(
!(!(!(
!(!(!(
!(
!(!(!(
!(!(
!(!(!(!(
!(
!(
!(
!(!(
!(!(
!(
!(
!(
!(!(
!(
!(!(
!(
!(
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
o
x RiverSawyer CreekLake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Figure 4-4City Trees by SizeCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Tree Size - Diameter at Breast Height (in)
!(Unknown
!(Less than 6-inches
!(Greater than or Equal to 6-inches
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 4-4 Tree Size.mxd7/15/20220 5,0002,500
Feet
±
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
^_
^_
^_
^_
^_
^_
^_
^_
^_
^_^_
^_
^_
^_^_
F
o
x RiverSawyer CreekLake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
7
15
16b
16a
43 42
40
38 37
35
26
29b
29a
6
39
Figure 4-5Potential Regional SMP LocationsCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Potential Regional SMPs
^_Dry Pond Retrofit
^_New Wet Pond
^_Wet Pond Retrofit
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 4-5 - Potential Regional SMPs.mxd7/25/20220 5,0002,500
Feet
±
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
o
x RiverSawyer CreekLake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Figure 4-6Potential Redevelopment AreasCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Potential RedevelopmentAreas by TMDL Reachshed
Fox River
Lake Butte des Morts
Lake Winnebago
Sawyer Creek
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 4-6 - Potential Redevelopment Areas.mxd7/19/20220 5,0002,500
Feet
±
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
F
ox Riv
er
Lake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Sawyer CreekFigure 4-7Potential New Development AreasCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Potential New Development Areasby Land Use
Conservation Residential
General Commercial
Industrial
Interstate Commercial
Light Density Residential
Medium & High DensityResidential
Mixed Use
Park
Areas outside City -Excluded from Analysis
Existing Developed
Rural Residential
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure 4-7 - Potential New Redevelopment Areas.mxd9/15/20220 6,0003,000
Feet
±
City of Oshkosh Stormwater Quality Management Plan
B-1
Oshkosh SWMP Final.docx
Appendix B: WPDES MS4 Permit & WDNR Guidance
1. WPDES Permit
Page 1 of 59 WPDES Permit No. WI-S050075-3-1
STATE OF WISCONSIN
DEPARTMENT OF NATURAL RESOURCES
GENERAL PERMIT TO DISCHARGE UNDER THE WISCONSIN POLLUTANT
DISCHARGE ELIMINATION SYSTEM
WPDES PERMIT NO. WI-S050075-3-1
In compliance with the provisions of ch. 283 Wis. Stats., and chs. NR 151 and 216, Wis. Adm. Code,
owners and operators of municipal separate storm sewer systems are permitted to discharge storm
water from all portions of the
MUNICIPAL SEPARATE STORM SEWER SYSTEM
owned or operated by the municipality to waters of the state in accordance with the conditions set forth
in this permit.
With written authorization by the Department, this permit will be used to cover a municipal separate
storm sewer system initially covered under a previous version of a municipal separate storm sewer
system general permit. The Start Date of coverage under this permit is the date of the Department
letter sent to the municipality authorizing coverage under this permit. The Department is required to
charge an annual permit fee to owners and operators authorized to discharge under this permit in
accordance with s. 283.33(9), Wis. Stats., and s. NR 216.08, Wis. Adm. Code.
State of Wisconsin Department of Natural Resources
For the Secretary
12/7/2021
By __________________________ ________________________________
Jill Schoen, Deputy Director Date Permit Signed/Issued
Bureau of Watershed Management
External Services Division
PERMIT EFFECTIVE DATE: May 1, 2019 EXPIRATION DATE: April 30, 2024
PERMIT MODIFICATION DATE: December 7, 2021
Page 2 of 59 WPDES Permit No. WI-S050075-3-1 TABLE OF CONTENTS
SECTION PAGE
1. APPLICABILITY CRITERIA 3
1.1 Permitted area 3
1.2 Authorized Discharges 3
1.3 Water Quality Standards 3
1.4 Outstanding and Exceptional Resource Waters 3
1.5 Impaired Waterbodies and Total Maximum
Daily Load Requirements 4
1.6 Wetlands 5
1.7 Endangered and Threatened Resources 5
1.8 Historic Property 5
1.9 General Storm Water Discharge Limitations 5
1.10 Obtaining Permit Coverage 6 1.11 Transfers 6
1.12 Exclusions 6
1.13 Compliance with Permit Requirements 7
2. PERMIT CONDITIONS 7
2.1 Public Education and Outreach 7
2.2 Public Involvement and Participation 9
2.3 Illicit Discharge Detection and Elimination 10
2.4 Construction Site Pollutant Control 12
2.5 Post-Construction Storm Water Management 15
2.6 Pollution Prevention 16
2.7 Storm Water Quality Management 21
2.8 Storm Sewer System Map 22
2.9 Annual Report 22
2.10 Cooperation 23
2.11 Amendments 24
2.12 Reapplication for Permit Coverage 24
3. COMPLIANCE SCHEDULE 24
4. GENERAL CONDITIONS 27
5. DEFINITIONS USED IN THIS PERMIT 30
APPENDICES
Appendix A: MS4 Permittees Subject to a TMDL Approved Prior to May 1, 2014 including
Applicable Updates 34 Appendix B: MS4 Permittees Subject to Milwaukee River Basin TMDL 46
Appendix C: MS4 Permittees Subject to a TMDL Approved After May 1, 2019 56
Page 3 of 59 WPDES Permit No. WI-S050075-3-1 1. APPLICABILITY CRITERIA
1.1 Permitted Area
This permit covers all areas under the ownership, control or jurisdiction of the permittee that contribute
to discharges from a municipal separate storm sewer system (MS4) that receives runoff from any of the
following:
1.1.1 An urbanized area, adjacent developing areas and areas whose runoff is connected or will
connect to a municipal separate storm sewer regulated under subch. I of NR 216, Wis. Adm.
Code; or
1.1.2 An area associated with a municipal population of 10,000 or more and a population
density of 1,000 or more per square mile, adjacent developing areas and areas whose runoff is
connected or will connect to an MS4 regulated under subch. I of NR 216, Wis. Adm. Code; or
1.1.3 An area that drains to an MS4 that is designated for permit coverage pursuant to s. NR
216.02(2) or 216.025, Wis. Adm. Code.
1.2 Authorized Discharges
This permit authorizes storm water point source discharges from the MS4 to waters of the state in the
permitted area. This permit also authorizes the discharge of storm water co-mingled with flows
contributed by process wastewater, non-process wastewater, and storm water associated with
industrial activity, provided the discharges are regulated by other WPDES permits or are discharges
which are not considered illicit discharges pursuant to section 2.3.1 of this permit.
1.3 Water Quality Standards
1.3.1 This permit specifies the conditions under which storm water may be discharged to waters
of the state for the purpose of achieving water quality standards contained in chs. NR 102
through 105, NR 140, and NR 207, Wis. Adm. Code. For the term of this permit, compliance with
water quality standards will be addressed by adherence to the requirements in this permit.
1.3.2 This permit does not authorize discharges that the Department determines will cause or
have reasonable potential to cause or contribute to an excursion above any applicable water
quality standards. Where such determinations have been made, the Department may notify the
municipality that an individual permit is necessary. However, the Department may authorize
coverage under this permit where the storm water management programs required under this
permit will include appropriate controls and implementation procedures designed to bring the
storm water discharge into compliance with water quality standards.
1.4 Outstanding and Exceptional Resource Waters
1.4.1 The permittee shall determine whether any part of its MS4 discharges to an outstanding
resource water (ORW) or exceptional resource water (ERW). ORWs and ERWs are listed in ss. NR
102.10 and 102.11, Wis. Adm. Code.
Note: An unofficial list of ORWs and ERWs may be found on the Department’s Internet site at:
https://dnr.wi.gov/topic/SurfaceWater/orwerw.html
Page 4 of 59 WPDES Permit No. WI-S050075-3-1 1.4.2 The permittee may not establish a new MS4 discharge of pollutants to an ORW or an ERW
unless the storm water management programs required under this permit are designed to
ensure that any new MS4 discharge of pollutants to an ORW or ERW will not exceed background
concentration levels within the ORW or ERW.
1.4.3 If the permittee has an existing MS4 discharge to an ORW, it may increase the discharge of
pollutants, either at the existing point of discharge or a new location, provided all of the
following are met:
a. The pollutant concentration within the receiving water and under the influence of the
existing discharge would not increase as compared to the level that existed prior to
coverage under this permit.
b. The increased discharge would not result in a violation of water quality standards.
1.4.4 If the permittee has an existing MS4 discharge to an ERW, it may increase the discharge of
pollutants if the increased discharge would not result in a violation of water quality standards.
1.5 Impaired Waterbodies and Total Maximum Daily Load Requirements
1.5.1 By March 31 of each odd-numbered year, the permittee shall determine whether any part
of its MS4 discharges to an impaired waterbody listed in accordance with section 303(d)(1) of
the federal Clean Water Act, 33 USC § 1313(d)(1)(C), and the implementing regulation of the US
Environmental Protection Agency, 40 CFR § 130.7(c)(1). For a permittee that determines that
any part of its MS4 does discharge to a listed impaired waterbody but for which there is no
United States Environmental Protection Agency (USEPA) approved Total Maximum Daily Load
(TMDL) for the pollutant of concern, the permittee shall include a written section in its storm
water management program that discusses the management practices and control measures it
will implement as part of its program to reduce, with the goal of eliminating, the discharge of
pollutants of concern that contribute to the impairment of the waterbody. This section of the
permittee’s program shall specifically identify control measures and practices that will
collectively be used to try to eliminate the MS4’s discharge of pollutants of concern that
contribute to the impairment of the waterbody.
Note: Every two years, the Department updates and publishes a list of waters considered
impaired under the Clean Water Act. The list is updated in even-numbered years. A list of
Wisconsin impaired waterbodies may be found on the Department’s Internet site at:
http://dnr.wi.gov/topic/impairedwaters/
1.5.2 For a permittee with an MS4 discharge of a pollutant of concern to a waterbody subject to
an USEPA approved TMDL under which the permittee is assigned a Wasteload Allocation (WLA),
the permittee shall meet the following requirements, in addition to the minimum control
measures described within Section 2 of the permit:
a. For a permittee subject to an USEPA approved TMDL approved prior to May 1, 2014,
the permittee shall comply with the provisions in Appendix A. Appendix A provides the
permit conditions for permittees subject to the Rock River Basin TMDL, Lower Fox River
Page 5 of 59 WPDES Permit No. WI-S050075-3-1 Basin and Lower Green Bay TMDL, Lake St. Croix Nutrient TMDL, Red Cedar River
(Tainter Lake, Menomin Lake) TMDL, or Beaver Dam Lake TMDL.
b. For a permittee subject to an USEPA approved TMDL approved after May 1, 2014,
and before May 1, 2019, the permittee shall comply with the provisions in Appendix B.
Appendix B provides the permit conditions for permittees subject to the Milwaukee
River Basin TMDL.
c. For a permittee subject to an USEPA approved TMDL approved after May 1, 2019, the
permittee shall comply with the provisions in Appendix C.
Note: The reports for Department and USEPA approved TMDLs are available from the
Department’s Internet site at: https://dnr.wi.gov/topic/TMDLs/tmdlreports.html
1.5.3 After the effective date of this permit, the permittee may not establish a new MS4
discharge of a pollutant of concern to an impaired waterbody or increase the discharge of a
pollutant of concern to an impaired waterbody unless the new or increased discharge causes
the receiving water to meet applicable water quality standards, or the USEPA have approved a
TMDL for the impaired waterbody.
1.6 Wetlands
The permittee’s MS4 discharge shall comply with the applicable wetland water quality standards
provisions in ch. NR 103, Wis. Adm. Code.
1.7 Endangered and Threatened Resources
The permittee’s MS4 discharge shall comply with the endangered and threatened resource protection
requirements of s. 29.604, Wis. Stats., and ch. NR 27, Wis. Adm. Code.
1.8 Historic Property
The permittee’s MS4 discharge may not affect any historic property that is listed property, or on the
inventory or on the list of locally designated historic places under s. 44.45, Wis. Stats., unless the
Department determines that the MS4 discharge will not have an adverse effect on any historic property
pursuant to s. 44.40(3), Wis. Stats.
1.9 General Storm Water Discharge Limitations
In accordance with s. NR 102.04, Wis. Adm. Code, practices attributable to municipal, industrial,
commercial, domestic, agricultural, land development or other activities shall be controlled so that all
surface waters including the mixing zone meet the following conditions at all times and under all flow
and water level conditions:
1.9.1 Substances that will cause objectionable deposits on the shore or in the bed of a body of
water, shall not be present in such amounts as to interfere with public rights in waters of the
state.
1.9.2 Floating or submerged debris, oil, scum or other material shall not be present in such
amounts as to interfere with public rights in waters of the state.
Page 6 of 59 WPDES Permit No. WI-S050075-3-1 1.9.3 Materials producing color, odor, taste or unsightliness shall not be present in such
amounts as to interfere with public rights in waters of the state.
1.9.4 Substances in concentrations or combinations which are toxic or harmful to humans shall
not be present in amounts found to be of public health significance, nor shall substances be
present in amounts which are acutely harmful to animal, plant or aquatic life.
1.10 Obtaining Permit Coverage
1.10.1 The owner or operator of an MS4 covered under a previous version of an MS4 permit
before the effective date of this permit shall be covered by this permit pursuant to written
authorization by the Department.
Note: The Department will notify in writing the owner or operator of an MS4 covered under a
previous version of an MS4 permit that this permit has been reissued and that the MS4 is
covered under it. However, the City of Madison and the City of Milwaukee are not eligible for
coverage under this permit.
1.10.2 Coverage under this permit does not become effective until the Department sends the
owner or operator a letter expressly authorizing coverage under this permit.
1.11 Transfers
Coverage under this permit is not transferable to another municipality without the express written
approval of the Department. If the permittee’s MS4 is annexed into another municipality, the permittee
shall immediately notify the Department by letter of the change. If the permittee ceases to own or
operate any MS4 regulated under this permit, the Department may terminate its coverage under this
permit.
1.12 Exclusions
The following are excluded from coverage and are not authorized under this permit:
1.12.1 Combined Sewer and Sanitary Sewer Systems
Discharges of water from a sanitary sewer or a combined sewer system conveying both sanitary
and storm water. These discharges are regulated under s. 283.31, Wis. Stats, and require an
individual permit.
1.12.2 Agricultural Facilities and Practices
Discharges from agricultural facilities and agricultural practices. “Agricultural facility" means a
structure associated with an agricultural practice. “Agricultural practice" means beekeeping;
commercial feedlots; dairying; egg production; floriculture; fish or fur farming; grazing; livestock
raising; orchards; poultry raising; raising of grain, grass, mint and seed crops; raising of fruits,
nuts and berries; sod farming; placing land in federal programs in return for payments in kind;
owning land, at least 35 acres of which is enrolled in the conservation reserve program under 16
USC § 3831 to 3836; and vegetable raising.
1.12.3 Other Excluded Discharges
Storm water discharges from industrial operations or land disturbing construction activities that
require separate coverage under a WPDES permit pursuant to subchs. II or III of ch. NR 216, Wis.
Page 7 of 59 WPDES Permit No. WI-S050075-3-1 Adm. Code. For example, while storm water from industrial or construction activity may
discharge to an MS4, this permit does not satisfy the need to obtain any other permits for those
discharges. This exclusion does not apply to the permittee’s responsibility to regulate
construction sites within its jurisdiction in accordance with sections 2.4 and 2.5 of this permit.
1.12.4 Indian Country
Storm water discharges within Indian Country. The federal Clean Water Act requires owners and
operators of storm water discharges within Indian Country in Wisconsin to obtain permit
coverage directly from the USEPA.
1.12.5 Non-MS4 Discharge
Storm water discharges that do not enter an MS4.
1.13 Compliance with Permit Requirements
Compliance with the requirements contained in this permit including the applicable appendices shall not
be contingent upon receiving financial assistance from the Department or any other public or private
grant or loan program.
2. PERMIT CONDITIONS
This permit establishes the following measurable goals, with a compliance schedule in section 3, for the
permittee to maintain compliance with the minimum control measures for their storm water
management program described under sections 2.1 through 2.6. The following permit conditions apply
to the permittee, unless the Department issues a written determination that a condition is not
appropriate under the circumstances. The permittee shall have a written storm water management
program that describes in detail how the permittee intends to comply with the permit’s requirements
for each minimum control measure.
2.1 Public Education and Outreach
The permittee shall maintain its public education and outreach program to increase the awareness of
storm water pollution impacts on waters of the state and to encourage changes in public behavior to
reduce such impacts. The permittee shall implement the following measurable goals:
2.1.1 Topics. The permittee shall address all eight topics at least once during the permit term
with a minimum of six topics being addressed each year. Topics may be repeated as necessary.
Permittees shall select from the following topic areas (Table 1):
Page 8 of 59 WPDES Permit No. WI-S050075-3-1 Table 1: Public Education and Outreach Topic Areas and Descriptions
# Topic Area Description
1 Illicit Discharge Detection
and Elimination
Promote detection and elimination of illicit discharges
and water quality impacts associated with such
discharges from municipal separate storm sewer
systems.
2
Household Hazardous Waste
Disposal/Pet Waste
Management/Vehicle
Washing
Inform and educate the public about the proper
management of materials that may cause storm water
pollution from sources including automobiles, pet waste,
household hazardous waste and household practices.
3
Yard Waste
Management/Pesticide and
Fertilizer Application
Promote beneficial onsite reuse of leaves and grass
clippings and proper use of lawn and garden fertilizers
and pesticides.
4 Riparian Corridor
Protection/Restoration
Promote the management of streambanks and
shorelines by riparian landowners to minimize erosion
and restore and enhance the ecological value of
waterways.
5 Water Conservation Promote infiltration of residential storm water runoff
from rooftop downspouts, driveways and sidewalks.
6
Construction
Sites/Infrastructure
Maintenance
Inform and educate those responsible for the design,
installation, and maintenance of construction site
erosion control practices and storm water management
facilities on how to design, install and maintain the
practices.
7 General Storm Water
Management Information
Identify businesses and activities that may pose a storm
water contamination concern, and educate those
specific audiences on methods of storm water pollution
prevention.
8 Green Infrastructure/Low
Impact Development
Promote environmentally sensitive land development
designs by developers and designers, including green
infrastructure and low impact development.
Note: Additional information on green infrastructure and low impact development may be
found on the USEPA’s Internet site at: https://www.epa.gov/green-infrastructure
Page 9 of 59 WPDES Permit No. WI-S050075-3-1 2.1.2 Delivery mechanism. The permittee shall use at least four public education delivery
mechanisms each year, and at least two shall be from the Active/Interactive Mechanisms
column in the Table 1:
Table 1: Public Education and Outreach Delivery Mechanisms (Active and Passive)
Active/Interactive Mechanisms Passive Mechanisms
• Educational activities (school
presentations, summer camps)
• Informational booth at event
• Targeted group training (contractors,
consultants, etc.)
• Government event (public hearing,
council meeting)
• Workshops
• Tours
• Passive print media (brochures at
front desk, posters, etc.)
• Distribution of print media (mailings,
newsletters, etc.) via mail or email
• Media offerings (radio and TV ads,
press release, etc.)
• Social media posts
• Signage
• Website
2.1.3 Target audience. The permittee shall identify the target audience for each public
education and outreach topic. Target audiences may include the general public, public
employees, residents, business, restaurants, contractors, developers, industries, agricultural,
and/or other appropriate audiences.
2.2 Public Involvement and Participation
The permittee shall maintain its public involvement and participation program, in compliance with
applicable state and local public notice requirements, to notify the public of activities required by this
permit and to encourage input and participation from the public regarding these activities. The
permittee shall implement the following measurable goals:
2.2.1 Permit activities. The permittee shall provide a minimum of one opportunity annually for
the public to provide input on each of the following permit activities: annual report, storm water
management program, and adoption or amendment of storm water related ordinances if
applicable.
2.2.2 Delivery mechanism. The permittee shall identify the public involvement and participation
delivery mechanism for each permit activity mentioned in section 2.2.1. Delivery mechanisms
may include public workshop, presentation of storm water information, government event
(public hearing, council meeting, etc.), citizen committee meeting, or website.
2.2.3 Volunteer activities. The permittee shall implement at a minimum one of the following
volunteer activities per year: group best management practice (BMP) installation, storm drain
stenciling, planting community rain garden, clean up event, stream monitoring, citizen
committee meeting, public workshop, presentation of storm water information, or other hands-
on event.
2.2.4 Target participants. The permittee shall identify the targeted participants for each permit
activity and volunteer activity. Participants may include general public, public employees,
Page 10 of 59 WPDES Permit No. WI-S050075-3-1 residents, business, restaurants, contractors, developers, industries, agricultural, and/or other
appropriate audience.
2.3 Illicit Discharge Detection and Elimination (IDDE)
The permittee shall continue to implement and enforce its program to detect and remove illicit
connections and discharges to the MS4. The permittee shall implement the following measurable goals:
2.3.1 IDDE control measures. An ordinance or other regulatory mechanism to prevent and
eliminate illicit discharges and connections to the MS4. At a minimum, the ordinance or other
regulatory mechanism shall:
a. Prohibit illicit discharges and the discharge, spilling or dumping of non-storm water
substances or materials into waters of the state or the MS4.
b. Identify non-storm water discharges or flows that are not considered illicit discharges.
Categories of non-storm water discharges that are not considered illicit discharges
include water line flushing, landscape irrigation, diverted stream flows, uncontaminated
groundwater infiltration, uncontaminated pumped groundwater, discharges from
potable water sources, foundation drains, air conditioning condensation, irrigation
water, lawn watering, individual residential car washing, flows from riparian habitats
and wetlands, fire-fighting and discharges authorized under a WPDES permit. However,
the occurrence of a discharge listed above may be considered an illicit discharge on a
case-by-case basis if the permittee or the Department identifies it as a significant source
of a pollutant to waters of the state.
c. Establish inspection and enforcement authority.
Note: Chapter NR 815, Wis. Adm. Code, regulates injection wells including storm water injection
wells. Construction or use of a well to dispose of storm water directly into groundwater is
prohibited under s. NR 815.11(5), Wis. Adm. Code.
2.3.2 IDDE field screening. On-going dry weather field screening shall be conducted at 100% of
the total major outfalls at least once during the term of the permit. Additionally, the permittee
shall select minor outfalls for annual on-going dry weather field screening during the term of the
permit. The permittee shall develop a prioritization procedure to assist with selecting minor
outfalls and consideration shall be given to hydrological conditions, total drainage area of the
site, population density of the site, traffic density, age of the structures or buildings in the area,
history of the area and land use types when selecting outfalls for annual field screening. At a
minimum, field screening shall be documented and include:
a. Visual Observation - A narrative description of visual observations including color,
odor, turbidity, oil sheen or surface scum, flow rate and any other relevant observations
regarding the potential presence of non-storm water discharges or illicit dumping.
b. Field Analysis - If flow is observed, a field analysis shall be conducted to determine
the presence of illicit non-storm water discharges or illicit dumping. The field analysis
shall include sampling for pH, total chlorine, total copper, total phenol and detergents,
unless the permittee elects instead to use detergent, ammonia, potassium and fluoride
Page 11 of 59 WPDES Permit No. WI-S050075-3-1 as the indicator parameters. Other alternative indicator parameters may be authorized
by the Department in writing.
(1) Field screening points shall, where possible, be located downstream of any
source of suspected illicit activity.
(2) Field screening points shall be located where practicable at the farthest
manhole or other accessible location downstream in the system. Safety of
personnel and accessibility of the location shall be considered in making this
determination.
Note: The Department’s MS4 Illicit Discharge Detection and Elimination guidance document
includes several recommendations regarding selection of outfalls for field screening, screening
frequency, indicator parameter selection, indicator parameter action levels and documentation.
The Illicit Discharge Detection and Elimination guidance is available on the Department’s
Internet site at: https://dnr.wi.gov/topic/stormwater/municipal/overview.html
2.3.3 IDDE source investigation and elimination. Written procedures for responding to known
or suspected illicit discharges, including an assessment of risks and the establishment to
response times. At a minimum, procedures shall be established for:
a. Investigating portions of the MS4 that, based on the results of field screening or other
information, indicate a reasonable potential for containing illicit discharges or other
sources of non-storm water discharges.
b. Responding to spills that discharge into and/or from the MS4 including tracking and
locating the source of the spill if unknown.
c. Preventing and containing spills that may discharge into or are already within the
MS4.
d. Promoting, publicizing, and facilitating public reporting of illicit discharges or water
quality impacts associated with discharges into or from MS4s through a central contact
point, including phone numbers for complaints and spill reporting, and publicize to both
internal permittee staff and the public.
e. Notifying the Department immediately in accordance with ch. NR 706, Wis. Adm.
Code, in the event that the permittee identifies a spill or release of a hazardous
substance, which has resulted or may result in the discharge of pollutants into waters of
the state. The Department shall be notified via the 24-hour toll free spill hotline at 1-
800-943-0003. The permittee shall cooperate with the Department in efforts to
investigate and prevent such discharges from polluting waters of the state.
f. Detecting and eliminating cross-connections and leakage from sanitary conveyance
systems into the MS4.
g. Providing the Department with advanced notice of the time and location of dye
testing within an MS4. Department notification prior to dye testing is required due to
Page 12 of 59 WPDES Permit No. WI-S050075-3-1 the likelihood that dye observed in waterways will be reported to the Department as an
illicit discharge or spill.
h. Documentation of the following information:
(1) Dates and locations of IDDE screenings conducted in accordance with section
2.3.2.
(2) Reports of alleged illicit discharges received, including dates of the reports,
and any follow-up actions taken by the permittee.
(3) Dates of discovery of all illicit discharges.
(4) Identification of outfalls, or other areas, where illicit discharge have been
discovered.
(5) Sources (including a description and the responsible party) of illicit
discharges (if known).
(6) Actions taken by the permittee, including dates, to address discovered illicit
discharges.
2.3.4 The permittee shall take appropriate action to known remove illicit discharges from its
MS4 system as soon as possible. If it will take more than 30 days to remove an illicit connection
or if the potential illicit discharge is from a facility with WPDES permit coverage, the Department
shall be contacted to discuss an appropriate action and/or timeframe for removal.
Notwithstanding this 30-day timeframe and notification of the Department, the permittee shall
be responsible for any known illicit connections to its MS4 system that are a significant risk to
human health and the environment.
2.3.5 In the case of interconnected MS4s, the permittee shall notify the appropriate municipality
within one working day of either of the following:
a. An illicit discharge that originates from the permittee’s permitted area that
discharges directly to a municipal separate storm sewer or property under the
jurisdiction of another municipality.
b. An illicit discharge that has been tracked upstream to the interconnection point with
or outfall from another municipality.
2.3.6 The name, title and phone number of the individuals responsible for responding to reports
of illicit discharges and spills shall be included in the illicit discharge response procedure.
2.4 Construction Site Pollutant Control
The permittee shall continue to implement and enforce its program to reduce the discharge of sediment
and construction materials from construction sites. The permittee shall implement the following
measurable goals:
Page 13 of 59 WPDES Permit No. WI-S050075-3-1 2.4.1 Construction site requirements and control measures. An ordinance or other regulatory
mechanism to require erosion and sediment control at construction sites and establish sanctions
to ensure compliance. At a minimum, the ordinance or other regulatory mechanism shall
establish or include:
a. Applicability and jurisdiction, pursuant to the authority provided to the permittee
under Wisconsin statutes, the ordinance shall apply to all construction sites with one
acre or more of land disturbance, and to sites of less than one acre if they are part of a
larger common plan of development or sale.
b. Requirements for design and implementation of erosion and sediment control
practices consistent with the criteria of those approved by the Department.
Note: Department approved erosion and sediment control technical standards may be
found on the Department’s Internet site at:
https://dnr.wi.gov/topic/stormwater/standards/const_standards.html
c. Construction site performance standards equivalent to those in ss. NR 151.11(6m),
(7), and (8), and 151.23(4m), (5), and (6), Wis. Adm. Code, to achieve the following
measurable goals:
(1) Best management practices for construction sites that, by design, discharge
no more than 5 tons per acre per year, or to the maximum extent practicable, of
the sediment load carried in runoff from initial grading to final stabilization.
(2) Best management practices for transportation facilities that, by design,
discharge no more than 5 tons per acre per year, or to the maximum extent
practicable, of the sediment load carried in runoff from initial grading to final
stabilization.
Note: The requirements for erosion and sediment control practices, sediment
performance standards, and preventive measures for non-transportation
facilities can be found in s. NR 151.11(6m), Wis. Adm. Code, and for
transportation facilities can be found in NR. 151.23(4m), Wis. Adm. Code.
d. Erosion and sediment control plan requirements for landowners of construction sites
equivalent to those contained in s. NR 216.46, Wis. Adm. Code.
e. Inspection and enforcement authority.
f. Requirements for construction site operators to manage waste such as discarded
building materials, concrete truck washout, chemicals, litter and sanitary waste at the
construction site to reduce adverse impacts to waters of the state.
Note: In accordance with section 2.10, when a town demonstrates to the Department that an
adequate county ordinance that meets the requirements of this permit is administered and
enforced within its town, then the town may be excused from having to adopt its own
Page 14 of 59 WPDES Permit No. WI-S050075-3-1 ordinance. Model ordinances for construction site erosion and sediment control can be found in
ch. NR 152, Wis. Adm. Code: https://docs.legis.wisconsin.gov/code/admin_code/nr/100/152
2.4.2 Construction site plan review. Written procedures for construction site plan review which
incorporate consideration of potential water quality impacts. Preconstruction erosion control
plan reviews shall be conducted for all construction sites with greater than one acre of land
disturbance.
2.4.3 Construction site inventory. Written procedures for the administration of the construction
site pollutant control program including the process for obtaining local approval, managing and
responding to complaints, tracking regulated construction sites, and construction site plan
receipt and consideration of information submitted by the public.
2.4.4 Construction site inspections and enforcement. Written procedures for construction site
inspection and enforcement of erosion and sediment control measures. By April 1, 2020, at a
minimum, the procedures shall establish:
a. Municipal departments or staff responsible for construction site inspections and
enforcement.
Note: The Department recommends that municipal construction site inspectors obtain
certification as a Soil Erosion Inspector pursuant to s. SPS 305.63, Wis. Adm. Code, for
more information:
https://dsps.wi.gov/Pages/Professions/SoilErosionInspector/Default.aspx
b. Construction site inspection frequency. Inspect all construction sites, at a minimum,
in accordance with the frequency specified in Table 2 below.
Table 2: Construction Site Inspection Frequency
Site Inspection Frequency
(1) All sites one acre
or more in size
• New projects shall be inspected within the first two
weeks of commencement of land disturbing activity
• All active sites shall be inspected at least once every 30
days
• All inactive sites shall be inspected at least once every
60 days
(2) Follow up
inspection
• Follow up inspections are required within 7 days of
any sediment discharge or inadequate control
measure, unless corrections were made and observed
by the inspector during initial inspection or corrections
were verified via photographs submitted to the
inspector
(3) Final inspection
• Confirm that all graded areas have reached final
stabilization and that all temporary control measures
are removed, and permanent storm water
management best management practices are installed
as designed
Page 15 of 59 WPDES Permit No. WI-S050075-3-1
c. Construction site inspection documentation. Compliance with the inspection
requirements in 2.4.4.a. and b. above, shall be determined by proper documentation
and maintenance of records of an established inspection program designed to inspect
all sites.
d. Enforcement mechanisms that will be used to obtain compliance.
2.5 Post-Construction Storm Water Management
The permittee shall continue to implement and enforce its program to require control of the quality of
discharges from areas of new development, infill, and redevelopment, after construction is completed.
The permittee shall implement the following measurable goals:
2.5.1 Site performance standards. An ordinance or other regulatory mechanism to regulate
post-construction storm water discharges from new development and redevelopment. At a
minimum, the ordinance or other regulatory mechanism shall establish or include:
a. Applicability and jurisdiction, pursuant to the authority provided to the permittee
under Wisconsin statutes, the ordinance shall apply to construction sites with one acre
or more of land disturbance, and sites of less than one acre if they are part of a larger
common plan of development or sale.
b. Requirements for design and implementation of post-construction storm water
management control practices consistent with the criteria of those approved by the
Department.
Note: Department approved post-construction storm water management control
technical standards may be found on the Department’s Internet site at:
https://dnr.wi.gov/topic/stormwater/standards/postconst_standards.html
c. For new development and infill, post-construction performance standards equivalent
to those in ss. NR 151.122 through 151.126 and 151.242 through 151.246, Wis. Adm.
Code, that meet the measurable goals for pollutant removal and post-construction
storm water treatment. Post-construction performance standards for new development
and infill may be more restrictive than those required in this section 2.5.1.c. if necessary
to comply with federally approved TMDL requirements.
d. For redevelopment, post-construction performance standards equivalent to or more
restrictive than those in ss. NR 151.122 through 151.126 and 151.242 through 151.246,
Wis. Adm. Code, that meet the measurable goals for pollutant removal and post-
construction storm water treatment.
e. Storm water plan requirements for landowners of construction sites equivalent to
those contained in s. NR 216.47, Wis. Adm. Code.
f. Long-term maintenance requirements for landowners and other persons responsible
for long-term maintenance of post-construction storm water control measures,
including requirements for routine inspection and maintenance of privately owned post-
Page 16 of 59 WPDES Permit No. WI-S050075-3-1 construction storm water control measures that discharge to the MS4 to maintain their
pollutant removal operating efficiency.
g. Inspection and enforcement authority.
Note: In accordance with section 2.10, when a town demonstrates to the Department that an
adequate county ordinance that meets the requirements of this permit is administered and
enforced within its town, then the town may be excused from having to adopt its own
ordinance. Model ordinances for post-construction storm water management can be found in
ch. NR 152, Wis. Adm. Code: https://docs.legis.wisconsin.gov/code/admin_code/nr/100/152
2.5.2 Tracking of control measures. Written procedures for the administration of the post-
construction storm water management program including the process for obtaining local
approval and responding to complaints.
2.5.3 Site plan review. Written procedures for post-construction site plan review which
incorporate consideration of potential water quality impacts. Post-construction site plan reviews
shall be conducted for all construction sites with greater than one acre of land disturbance.
Note: The Department recommends that municipal staff reviewing plans obtain training on
post-construction plan review.
2.5.4 Long-term maintenance, inspections and enforcement. Written procedures that will be
used by the permittee to ensure the long-term maintenance of all storm water management
facilities in the MS4 boundary. The procedures shall include:
a. A mechanism for tracking regulated sites.
b. At a minimum, long-term maintenance inspections shall occur once per permit term.
c. Inspection documentation.
d. Follow up enforcement with timeframes for corrective maintenance.
2.6 Pollution Prevention
The permittee shall continue to implement its pollution prevention program to prevent or reduce
pollutant runoff from the MS4 to waters of the state. The permittee shall implement the following
measurable goals:
2.6.1 Storm water management facilities. Update and maintain an inventory of municipally
owned or operated structural storm water facilities such as wet detention ponds, bioretention
devices, infiltration basins and trenches, permeable pavement, proprietary sedimentation
devices, vegetated swales, or any similar practices or devices used to meet a water quality
requirement under this permit. At a minimum, the inventory shall be maintained in a tabular
format and contain the following information for each structural storm water facility:
a. A key corresponding to the location of the best management practice on the storm
sewer system map required under section 2.8.
Page 17 of 59 WPDES Permit No. WI-S050075-3-1
b. The name and a description of the best management practice, including the type and
year constructed.
c. A confirmation of whether each of the following elements are or are not available:
(1) A maintenance plan with inspection procedures and schedule.
(2) As-built plans.
(3) If owned by another entity but used by the permittee to meet a water
quality requirement in this permit, written documentation that the permittee
has permission from the owner to use the best management practice for this
purpose.
2.6.2 For each best management practice inventoried under section 2.6.1, the permittee shall
develop and implement a maintenance plan with inspection procedures and schedule to
maintain the pollutant removal operating efficiency of the practice in compliance with any water
quality requirement under this permit. Documentation of inspections and maintenance
activities shall be maintained.
Note: Chapter NR 528, Wis. Adm. Code, Management of Accumulated Sediment from Storm
Water Management Structures, establishes a process to regulate sediment removal and use to
help storm water pond owners manage storm water pond sediment. Information on NR 528 and
managing accumulated sediment from storm water ponds is available through the Department’s
Internet site at: https://dnr.wi.gov/topic/waste/nr528.html
2.6.3 Public works yards and other municipally owned properties. The storm water pollution
prevention plans (SWPPPs) for municipal garages, storage areas, and other sources of storm
water pollution from municipal facilities located within the permitted area shall be maintained
and updated annually as needed and shall include the information in sections 2.6.3.a. When a
SWPPP is updated, it shall be submitted to the Department with the annual report.
a. SWPPPs shall include the following information:
(1) The physical locations of each facility with a key corresponding to the
locations on the storm sewer system map required under section 2.8.
(2) The contact information for the individuals with overall responsibility for
each facility.
(3) A map of each facility, drawn to scale, and including the following features:
i. The locations and descriptions of major activities and storage areas.
ii. Identification of drainage patterns, potential sources of storm water
contamination, and discharge points.
Page 18 of 59 WPDES Permit No. WI-S050075-3-1 iii. Identification of nearby receiving waters or wetlands.
iv. Identification of connections to the permittees MS4.
(4) A description of procedures, good housekeeping activities, and any best
management practices installed to reduce or eliminate storm water
contamination.
(5) A maintenance plan with inspection procedures and schedule for each
facility to identify deficiencies, necessary improvements and/or repairs, assess
effectiveness, and address new or unaddressed potential sources of storm
water contamination.
(6) Spills prevention and response standard operating procedures.
b. The permittee is not required to comply with section 2.6.3 if the permittee certifies
that the municipal facility qualifies for no exposure with the Department’s concurrence.
(1) No exposure means that the facility shall have all materials and activities
protected by a storm-resistant shelter to prevent exposure to storm water.
Materials or activities include material handling equipment or activities,
industrial machinery, raw materials, intermediate products, by-products, final
products or waste products. Material handling activities include the storage,
loading and unloading, transportation or conveyance of any raw material,
intermediate product, final product or waste product.
(2) The permittee shall certify for no exposure for each facility at least once
each permit term. The permittee shall submit a letter requesting no exposure,
an inspection report of the site, and photos of all materials or activities at the
site. The photo locations shall be labeled on an aerial photo diagram.
2.6.4 Measures to reduce municipal sources of storm water contamination within source water
protection areas.
Note: Wisconsin’s source water assessment program information may be found on the
Department’s Internet site at:
https://dnr.wi.gov/topic/drinkingwater/sourcewaterprotection.html
2.6.5 Collection services/Storm sewer system maintenance activities.
a. Street sweeping. If routine street sweeping is utilized to meet a water quality
requirement under this permit, the permittee shall maintain documentation of the
number and type of equipment used, standard operating procedures, an estimate of the
number of lane-miles swept annually, and an estimate of the weight in tons of material
collected annually.
b. Catch basins. If routine cleaning of catch basins with sumps is utilized to meet a water
quality requirement under this permit, the permittee shall maintain documentation of
Page 19 of 59 WPDES Permit No. WI-S050075-3-1 the number of catch basins inspected, the number of catch basins cleaned, standard
operating procedures, and an estimate of the weight in tons of material collected
annually.
c. Material handling and disposal. Material collected under a. and b. of this section shall
be handled and stored in a manner that prevents contamination of storm water runoff
and shall be disposed of or beneficially reused in accordance with applicable solid and
hazardous waste statutes and administrative codes. Non-storm water discharges to
waters of the state associated with dewatering and drying material collected under
sections a. and b. of this section are not authorized by this permit.
Note: Information on managing waste and materials is available on the Department’s
Internet site at: https://dnr.wi.gov/topic/Waste/. Information on WPDES permits for
non-storm water discharges is available on the Department’s Internet site at:
https://dnr.wi.gov/topic/wastewater/
d. Leaf management. Proper management of leaves and grass clippings, which may
include instructions to property owners for on-site composting, on-site beneficial reuse,
or yard waste drop-off as opposed to a municipal collection program. On-site
management and/or drop-off shall be communicated to property owners in accordance
with the public education and outreach program implemented under section 2.1 of this
permit. If the permittee has a municipal collection program, collected material shall be
handled and stored in a manner that prevents contamination of storm water runoff. For
a municipal leaf collection program, the permittee shall maintain the following
documentation:
(1) A description of the leaf collection program, including the type of pick-up
methodology and equipment used, timing of associated street cleaning,
standard operating procedures, schedule and frequency, and instructions for
property owners.
(2) An estimate of the weight in tons of material collected annually.
(3) Municipally operated leaf disposal locations with a key corresponding to the
locations on the storm sewer system map required under section 2.8. If the
disposal location is outside of the MS4 boundary, then the permittee can
provide documentation if the disposal is taken elsewhere.
Note: The Department has developed “Interim Municipal Phosphorus Reduction
Credit for Leaf Management Programs” guidance to assist permitted MS4s on
creditable phosphorus reduction through leaf collection and management. The
guidance document may be found on the Department’s Internet site at:
https://dnr.wi.gov/topic/stormwater/standards/ms4_modeling.html
2.6.6 Winter Road Management. If road salt or other deicers are applied by the permittee or a
contractor on behalf of the permittee, no more shall be applied than necessary to maintain
public safety. Documentation on deicing activities shall be performed by the permittee or a
contractor on behalf of the permittee and include the following:
Page 20 of 59 WPDES Permit No. WI-S050075-3-1
a. Contact information for the individuals with overall responsibility for winter roadway
maintenance.
b. A description of the types of deicing products used.
c. The amount of deicing product used per month.
d. A description of the type of equipment used.
e. An estimate of the number of lane-miles treated with deicing products for the
roadways that the permittee is responsible for, and an estimate in acres of the total
area of municipally-owned parking lots treated with deicing products by the permittee
or contractor.
f. If applicable, snow disposal locations with a key corresponding to the locations on the
storm sewer system map required under section 2.8.
Note: Snow treatment and disposal guidance for municipalities is available through the
Department’s Internet site at: https://dnr.wi.gov/topic/stormwater/publications.html
g. A description of anti-icing, pre-wetting and brining, equipment calibration, pavement
temperature monitoring, and/or salt reduction strategies implemented or being
considered, and/or alternative products.
h. Other measurable data or information that the permittee uses to evaluate or modify
its deicing activities.
Note: The Wisconsin Department of Transportation (WisDOT) “Highway Maintenance Manual,”
Chapter 6, contains guidelines on winter maintenance including application of road salt and
other deicers. Chapter 6 is available on the WisDOT’s Internet site at:
https://wisconsindot.gov/Pages/doing-bus/local-gov/hwy-mnt/mntc-manual/chapter06.aspx.
The WisDOT highway salt storage requirements are contained in ch. Trans 277, Wis. Adm. Code.
2.6.7 Nutrient management. Application of turf and garden fertilizers on municipally controlled
properties (such as parks, athletic fields, golf courses), with pervious surfaces over 5 acres each,
in accordance with a site-specific nutrient application schedule based on appropriate soil tests.
Note: To assist permittees with this requirement, the Department has developed a technical
standard for turf nutrient management. These documents may be found on the Department’s
Internet site at: https://dnr.wi.gov/topic/stormwater/standards/turf_nutrient.html
2.6.8 Environmentally sensitive development. Consideration of environmentally sensitive land
development designs for municipal projects, including green infrastructure and low impact
development, which shall be designed, installed, and maintained to comply with a water quality
requirement under this permit.
Page 21 of 59 WPDES Permit No. WI-S050075-3-1 Note: Additional information on green infrastructure and low impact development may be
found on the following USEPA Internet sites:
https://www.epa.gov/green-infrastructure
https://www.epa.gov/nps/urban-runoff-low-impact-development
2.6.9 Internal training and education. At a minimum, the permittee shall hold one annual
training event for appropriate municipal staff and other personnel involved in implementing
each of the elements of the pollution prevention program under this section 2.6.
Documentation shall be maintained of the date, the number of people attending the training,
the names of each person attending and a summary of their responsibilities, and the content of
the training. The permittee shall inform contractors performing any services to implement
section 2.6 of the permit requirements and expectations. The permittee shall also inform their
elected officials of the permit requirements and expectations.
2.7 Storm Water Quality Management
The permittee shall implement its municipal storm water quality management program. This program
shall maintain compliance with the developed urban area performance standards of s. NR
151.13(2)(b)1., Wis. Adm. Code, for those areas of the municipality that were not subject to the post-
construction performance standards of ss. NR 151.12 or 151.24, or ss. NR 151.122 through 151.126, or
ss. 151.242 through 151.246, Wis. Adm. Code. The permittee shall implement the following measurable
goals:
2.7.1 To the maximum extent practicable, implementation and maintenance of all storm water
management practices necessary to meet the more restrictive total suspended solids reduction
of either of the following:
a. The permittee shall maintain all source area controls, structural storm water
management facilities, and non-structural storm water best management practices that
the permittee implemented on or before July 1, 2011, to achieve a reduction of 20% or
more of total suspended solids carried by storm water runoff from existing development
to waters of the state. All structural storm water management facilities utilized to meet
this requirement shall be inventoried and maintained in accordance with sections 2.6.1
and 2.6.2.
b. A 20% reduction in the annual average mass of total suspended solids discharging
from the MS4 to surface waters of the state as compared to implementing no storm
water management controls. All source area controls, structural storm water
management facilities, and non-structural control practices implemented to achieve the
20% reduction in total suspended solids shall be maintained. All structural storm water
management facilities utilized to meet this requirement shall be inventoried and
maintained in accordance with sections 2.6.1 and 2.6.2.
Note: The total suspended solids reduction requirement applies to storm water runoff
from areas of urban land use and is not applicable to agricultural or rural land uses and
associated roads. Additional MS4 modeling guidance for modeling the total suspended
solids control is available on the Department’s Internet site at:
https://dnr.wi.gov/topic/stormwater/standards/ms4_modeling.html. The permittee
may elect to meet the applicable total suspended solids standard above on a watershed
Page 22 of 59 WPDES Permit No. WI-S050075-3-1 or regional basis by working with other permittees to provide regional treatment that
collectively meets the standard.
2.8 Storm Sewer System Map
The permittee shall maintain its MS4 map. The storm sewer system map shall be updated annually as
needed for changes occurring in the permitted area boundaries. The municipal storm sewer system map
shall include:
2.8.1 Identification of waters of the state, name and classification of receiving waters,
identification of whether the receiving water is an ORW, ERW or listed as an impaired water
under s. 303(d) of the Clean Water Act, storm water drainage basin boundaries for each MS4
outfall, and the municipal separate storm sewer conveyance systems including direction of flow.
2.8.2 Identification of any known wetlands, endangered or threatened resources, and historical
property, as defined in sections 1.6 through 1.8 of this permit, which might be affected.
2.8.3 Identification of all known MS4 outfalls discharging to waters of the state and other
MS4s. Major outfalls shall be uniquely identified.
2.8.4 Location of any known discharge to the MS4 that has been issued WPDES permit coverage
by the Department. A list of WPDES permit holders in the permittee’s area may be obtained
from the Department.
2.8.5 Location of municipally owned or operated structural storm water management facilities
including detention basins, infiltration basins, and manufactured treatment devices. If the
permittee will be taking total suspended solids credit for pollutant removal from privately-
owned facilities, they shall be identified.
2.8.6 Identification of publicly owned parks, recreational areas and other open lands.
2.8.7 Location of municipal garages, storage areas and other public works facilities.
2.8.8 Identification of streets.
2.9 Annual Report
The permittee shall submit an annual report for each calendar year to the Department by March 31 of
the following year. The permittee shall invite the municipal governing body, interest groups and the
general public to review and comment on the annual report. The annual report shall include:
2.9.1 The status of implementing the permit requirements, status of meeting measurable
program goals and compliance with permit schedules.
2.9.2 A fiscal analysis which includes the annual expenditures and budget for the reporting year,
and the budget for the next year.
2.9.3 A summary of the number and nature of inspections and enforcement actions conducted
to ensure compliance with the required ordinances.
Page 23 of 59 WPDES Permit No. WI-S050075-3-1 2.9.4 Identification of any known water quality improvements or degradation in the receiving
water to which the permittee’s MS4 discharges. Where degradation is identified, identify why
and what actions are being taken to improve the water quality of the receiving water.
2.9.5 An evaluation of program compliance, the appropriateness of identified best management
practices, and progress towards achieving identified measurable goals. Any program changes
made as a result of this evaluation shall be identified and described in the annual report. For any
identified deficiencies towards achieving the requirements under section 2 of this permit or lack
of progress towards meeting a measurable goal, the permittee shall initiate program changes to
improve their effectiveness.
2.9.6 If applicable, notice that the permittee is relying on another municipality or entity to
satisfy any of the permit requirements and a description of the arrangement where a permit
requirement is being met in this manner.
2.9.7 A duly authorized representative of the permittee shall sign and certify the annual report
and include a statement or resolution that the permittee’s governing body or delegated
representatives have reviewed or been apprised of the content of the annual report.
2.9.8. The annual report and other required reports, and permit compliance documents shall be
submitted electronically through the Department’s electronic reporting system.
Note: The Department’s electronic reporting system is Internet-based and available at:
https://dnr.wi.gov/permits/water/. Municipal storm water permit eReporting information and
user support tools can be found at:
https://dnr.wi.gov/topic/stormwater/municipal/eReporting.html
2.10 Cooperation
The permittee may, by written agreement, implement this permit with another municipality or contract
with another entity to perform one or more of the conditions of this permit. The permittee is ultimately
responsible for compliance with the conditions of this permit. The permittee may rely on another
municipality or contract with another entity to satisfy a condition of this permit if all of the following are
met:
2.10.1 The other municipality or entity implements the required control measure or permit
requirement.
2.10.2 A particular control measure, or component thereof, is at least as stringent as the
corresponding permit requirement.
2.10.3 The other municipality or entity agrees to implement a control measure or permit
requirement on the permittee’s behalf. This shall be shown by formal written agreement, signed
by both parties’ authorized representatives. The agreement shall be explicit as to which specific
permit conditions are being covered by which municipality or other entity. Copies of current
agreements shall be submitted with the annual report or to the Department upon request.
Note: If a county is implementing and enforcing adequate storm water ordinances within a town, the
town would then not have to adopt its own ordinance. However, the town, as the permittee, is still
Page 24 of 59 WPDES Permit No. WI-S050075-3-1 expected to evaluate how the county is implementing and enforcing the ordinance in the town’s
permitted area, to verify the county is meeting the permit condition. Another example, if another entity
agrees to implement the permit condition of long-term maintenance inspections, the permittee must
evaluate that the entity is completing inspections as agree upon. The permittee should not assume that
another entity is implementing a permit condition as required because the permittee remains
responsible for compliance with the conditions of this permit.
2.11 Amendments
The permittee shall amend a program required under this permit as soon as possible if the permittee
becomes aware that it does not meet a requirement of this permit. The permittee shall amend its
program if notified by the Department that a program or procedure is insufficient or ineffective in
meeting a requirement of this permit. The Department notice to the permittee may include a deadline
for amending and implementing the amendment.
2.12 Reapplication for Permit Coverage
To remain covered after the expiration date of this permit, pursuant to s. NR 216.09, Wis. Adm. Code,
the permittee shall reapply to the Department at least 180 days prior to the expiration date of this
permit for continued coverage under a reissued version of this permit.
3. COMPLIANCE SCHEDULE
The permittee shall comply with the specific permit conditions contained in sections 1 and 2 according
to the schedule in this section 3 and Table 4. The permittee shall begin implementing any updates to its
storm water management programs no later than March 31, 2020. Required reports and permit
compliance documents shall be submitted electronically through the Department’s electronic reporting
system.
Note: The Department’s electronic reporting system is Internet-based and available at:
https://dnr.wi.gov/permits/water/. Municipal storm water permit eReporting information and user
support tools can be found at: https://dnr.wi.gov/topic/stormwater/municipal/eReporting.html
3.1 Impaired Waterbodies and Total Maximum Daily Loads
3.1.1 The permittee shall determine whether any part of its MS4 discharges to an
impaired waterbody as required under section 1.5.1 of this permit by March 31 of each
odd-numbered year.
3.1.2 If the permittee is subject to TMDL requirements under section 1.5 of this permit,
the permittee shall submit information to the Department in accordance with the
schedule as required in the applicable Appendix of this permit.
3.2 Public Outreach and Education
The permittee shall submit to the Department the public education and outreach program
developed for the term of this permit as required under section 2.1 of this permit by March 31,
2020.
Page 25 of 59 WPDES Permit No. WI-S050075-3-1 3.3 Public Involvement and Participation
The permittee shall submit to the Department the public involvement and participation program
developed for the term of this permit as required under section 2.2 of this permit by March 31,
2020.
3.4 Illicit Discharge Detection and Elimination
The permittee shall submit to the Department the illicit discharge detection and elimination
program developed for the term of this permit as required under section 2.3.2 to 2.3.6 of this
permit by March 31, 2020.
3.5 Construction Site Pollutant Control
The permittee shall submit to the Department the construction site pollutant control program
developed for the term of this permit as required under sections 2.4.2 to 2.4.4 of this permit by
March 31, 2020.
3.6 Post-Construction Storm Water Management
The permittee shall submit to the Department the post-construction storm water management
program developed for the term of this permit as required under sections 2.5.2 to 2.5.4 of this
permit by March 31, 2020.
3.7 Pollution Prevention
3.7.1 The permittee shall submit to the Department the municipal storm water
management facility inventory as required under section 2.6.1 of this permit by March
31, 2020. Include with the annual report submittal via the Department’s electronic
reporting system. When the inventory is updated, it shall be submitted by March 31 of
each year to the Department.
3.7.2 The permittee shall submit to the Department the maintenance plan for municipal
storm water management facilities as required under section 2.6.2 of this permit by
March 31, 2020.
3.7.3 The permittee shall update SWPPPs for municipally owned properties as needed
as required under section 2.6.3 of this permit. When a SWPPP is updated, it shall be
submitted by March 31 of each year to the Department.
3.8 Storm Water Quality Management
The permittee shall report compliance with the developed urban area performance standards as
required under section 2.7 of this permit by March 31 of each year.
3.9 Storm Sewer System Map
The permittee shall update the storm sewer system map as needed as required under section
2.8 of this permit. When the MS4 map is updated, it shall be submitted by March 31 of each year to the Department with the annual report submittal via the Department’s electronic
reporting system.
Page 26 of 59 WPDES Permit No. WI-S050075-3-1 3.10 Annual Report
The permittee shall submit to the Department an annual report as required under section 2.9 of
this permit for each calendar year by March 31 of the following year. The annual report and
other required reports, and permit compliance documents shall be submitted electronically
through the Department’s electronic reporting system.
Table 3: Compliance Schedule for Permit Requirements
PERMIT SECTION ACTIVITY COMPLIANCE DATE COMMENTS
Section 1.5.1 Identify discharges to an
impaired waterbody
Within 90 days of start date
and by March 31 of each
odd-numbered year
thereafter
All permittees
Section 1.5.2 Total maximum daily load
implementation
See applicable Appendix. Applies to a permittee with an MS4
discharge of a pollutant of concern to
a waterbody subject to an USEPA
approved TMDL that assigns the
permittee a wasteload allocation.
Section 2.1 Public Education and Outreach –
Submit public education and
outreach program for the permit
term with annual report
March 31, 2020 All permittees
Section 2.2 Public Involvement and
Participation – Submit public
involvement and participation
program for the permit term with
annual report
March 31, 2020 All permittees
Section 2.3.2 to
2.3.6
Illicit Discharge Detection and
Elimination – Submit illicit
discharge detection and
elimination program for the
permit term with annual report
March 31, 2020 All permittees
Section 2.4.2 to
2.4.4
Construction Site Pollutant
Control – Submit construction
site pollutant control program for
the permit term with annual
report
March 31, 2020 All permittees
Section 2.5.2 to
2.5.4
Post-Construction Storm Water
Management – Submit post-
construction storm water
management program for the
permit term with annual report
March 31, 2020 All permittees
Section 2.6 Pollution Prevention – Section
2.6.1, submit the municipal storm
water management facility
inventory with annual report
March 31, 2020, and annually
thereafter (if updates)
All permittees
Page 27 of 59 WPDES Permit No. WI-S050075-3-1
4. GENERAL CONDITIONS
The conditions in s. NR 205.07(1) and (3), Wis. Adm. Code, are incorporated by reference in this permit.
The permittee shall be responsible for meeting these requirements, except for s. NR 205.07(1)(n), Wis.
Adm. Code, which does not apply to facilities covered under general permits. Some of these
requirements are outlined below. Requirements not specifically outlined below can be found in s. NR
205.07(1) and (3), Wis. Adm. Code.
4.1 Duty to Comply: The permittee shall comply with all conditions of the permit. Any act of
noncompliance with this permit is a violation of this permit and is grounds for enforcement action or
withdrawal of permit coverage under this permit and issuance of an individual permit. If the permittee
files a request for an individual WPDES permit or a notification of planned changes or anticipated
noncompliance, this action by itself does not relieve the permittee of any permit condition.
4.2 Enforcement Action: The Department is authorized under s. 283.89 and 283.91, Wis. Stats., to utilize
citations or referrals to the Wisconsin Department of Justice to enforce the conditions of this permit.
Violation of a condition of this permit is subject to a fine of up to $10,000 per day of the violation.
4.3 Compliance Schedules: Reports of compliance or noncompliance with interim and final
requirements contained in any compliance schedule of the permit shall be submitted in writing within
14 days after the scheduled due date, except that progress reports shall be submitted in writing on or
before each schedule date for each report. Any report of noncompliance shall include the cause of
noncompliance, a description of remedial actions taken, and an estimate of the effect of the
noncompliance on the permittee’s ability to meet the remaining scheduled due dates.
4.4 Noncompliance
4.4.1 Upon becoming aware of any permit noncompliance that may endanger public health or
the environment, the permittee shall report this information by a telephone call to the
Pollution Prevention – Section
2.6.2, submit the maintenance
plan for municipal storm water
management facilities with annual report
March 31, 2020 All permittees
Pollution Prevention – Section
2.6.3, submit SWPPPs for
municipally owned properties
with annual report
March 31 of each year
reporting on previous
calendar year (if updates)
All permittees
Section 2.7 Storm Water Quality
Management – Report TSS
percent reduction
March 31 of each year
reporting on previous
calendar year
All permittees
Section 2.8 Storm sewer system map -
Submit map with annual report
March 31, 2020, and annually
thereafter (if updates)
All permittees
Section 2.9 Submit Annual Report March 31 of each year
reporting on previous
calendar year
All permittees
Page 28 of 59 WPDES Permit No. WI-S050075-3-1 Department regional storm water specialist within 24 hours. A written report describing the
noncompliance shall be submitted to the Department regional storm water specialist within 5
days after the permittee became aware of the noncompliance. The Department may waive the
written report on a case-by-case basis based on the oral report received within 24 hours. The
written report shall contain a description of the noncompliance and its cause; the period of
noncompliance, including exact dates and times; the steps taken or planned to reduce,
eliminate, and prevent reoccurrence of the noncompliance; and if the noncompliance has not
been corrected, the length of time it is expected to continue.
4.4.2 Reports of any other noncompliance not covered under General Conditions sections 3.3,
3.4.1, or 3.6. shall be submitted with the annual report. The reports shall contain all the
information listed in General Conditions section 3.4.1.
4.5 Duty to Mitigate: The permittee shall take all reasonable steps to minimize or prevent any adverse
impact on the waters of the state resulting from noncompliance with the permit.
4.6 Spill Reporting: The permittee shall immediately notify the Department, in accordance with s.
292.11(2)(a), Wis. Stats., which requires any person who possesses or controls a hazardous substance or
who causes the discharge of a hazardous substance to notify the DNR immediately of any discharge not
authorized by the permit. The discharge of a hazardous substance that is not authorized by this permit
or that violates this permit may be a hazardous substance spill. To report a hazardous substance spill,
call the DNR's 24-hour HOTLINE at 1-800-943-0003.
Note: For details on state and federal reportable quantities, visit:
https://dnr.wi.gov/topic/Spills/define.html
4.7 Proper Operation and Maintenance: The permittee shall at all times properly operate and maintain
all facilities and systems of treatment and control which are installed or used by the municipality to
achieve compliance with the conditions of the permit and the storm water management plan. Proper
operation and maintenance includes effective performance, adequate funding, adequate operator
staffing and training and adequate laboratory and process controls, including appropriate quality
assurance procedures. This provision requires the operation of back-up or auxiliary facilities or similar
systems only when necessary to achieve compliance with conditions of this permit.
4.8 Bypass: The permittee may temporarily bypass a storm water treatment facility if necessary for
human safety or maintenance to assure efficient operation. A bypass shall comply with the general
storm water discharge limitations in Section 1.9 of this permit. Notification of the Department is not
required for these types of bypasses. Any other bypass is prohibited.
Note: A discharge from a storm water treatment facility that exceeds the operational design capacity of
the facility is not considered a bypass.
4.9 Duty to Halt or Reduce Activity: Upon failure or impairment of storm water management practices
identified in the storm water management program, the permittee shall, to the extent practicable and
necessary to maintain permit compliance, modify or curtail operations until the storm water
management practices are restored or an alternative method of storm water pollution control is
provided.
Page 29 of 59 WPDES Permit No. WI-S050075-3-1 4.10 Removed Substances: Solids, sludges, filter backwash or other pollutants removed from or
resulting from treatment or control of storm water shall be stored and disposed of in a manner to
prevent any pollutant from the materials from entering the waters of the state, and to comply with all
applicable federal, state, and local regulations.
4.11 Additional Monitoring: If a permittee monitors any pollutant more frequently than required by the
permit, the results of that monitoring shall be reported to the Department in the annual report.
4.12 Inspection and Entry: The permittee shall allow authorized representatives of the
Department, upon the presentation of credentials, to:
4.12.1 Enter upon the municipal premises where a regulated facility or activity is located or
conducted, or where records are required to be maintained under the conditions of the permit;
4.12.2 Have access to and copy, at reasonable times, any records that are required under the
conditions of the permit;
4.12.3 Inspect at reasonable times any facilities, equipment (including monitoring and control
equipment), practices or operations regulated or required under the permit; and
4.12.4 Sample or monitor at reasonable times, for the purposes of assuring permit compliance,
any substances or parameters at any location.
4.13 Duty to Provide Information: The permittee shall furnish the Department, within a reasonable
time, any information which the Department may request to determine whether cause exists for
modifying, terminating, suspending revoking or reissuing the permit or to determine compliance with
the permit. The permittee shall give advance notice to the Department of any planned changes to the
storm water management program which may result in noncompliance with permit requirements. The
permittee shall also furnish the Department, upon request, copies of records required to be kept by the
permittee.
4.14 Property Rights: The permit does not convey any property rights of any sort, or any exclusive
privilege. The permit does not authorize any injury or damage to private property or an invasion of
personal rights, or any infringement of federal, state or local laws or regulations.
4.15 Other Information: Where the permittee becomes aware that it failed to submit any relevant facts
in applying for permit coverage or submitted incorrect information in any plan or report sent to the
Department, it shall promptly submit such facts or correct information to the Department.
4.16 Records Retention: The permittee shall retain records of all monitoring information, copies of all
reports required by the permit, and records of all data used to complete the notice of intent for a period
of at least 5 years from the date of the sample, measurement, report or application. The permittee shall
retain records documenting implementation of the minimum control measures in sections 2.1 through
2.6 of this permit for a period of at least 5 years from the date the record was generated.
4.17 Permit Actions: Under s. 283.35, Wis. Stats., the Department may withdraw a permittee from
coverage under this general permit and issue an individual permit for the municipality if: (a) The
municipality is a significant contributor of pollution; (b) The municipality is not in compliance with the
Page 30 of 59 WPDES Permit No. WI-S050075-3-1 terms and conditions of the general permit; (c) A change occurs in the availability of demonstrated
technology or practices for the control or abatement of pollutants from the municipality; (d) Effluent
limitations or standards are promulgated for a point source covered by the general permit after the
issuance of that permit; or (e) A water quality management plan containing requirements applicable to
the municipality is approved. In addition, as provided in s. 283.53, Wis. Stats., after notice and
opportunity for a hearing this permit may be suspended, modified or revoked, in whole or in part, for
cause. If the permittee files a request for a permit modification, termination, suspension, revocation and
reissuance, or submits a notification of planned changes or anticipated noncompliance, this action by
itself does not relieve the permittee of any permit condition.
4.18 Signatory Requirements: All applications, reports or information submitted to the
Department shall be signed by a ranking elected official, or other person authorized by those
responsible for the overall operation of the MS4 and storm water management program activities
regulated by the permit. The representative shall certify that the information was gathered and
prepared under his or her supervision and, based on report from the people directly under supervision
that, to the best of his or her knowledge, the information is true, accurate, and complete.
4.19 Attainment of Water Quality Standards after Authorization: At any time after authorization, the
Department may determine that the discharge of storm water from a permittee’s MS4 may cause, have
the reasonable potential to cause, or contribute to an excursion of any applicable water quality
standard. If such determination is made, the Department may require the permittee to do one of the
following:
4.19.1 Develop and implement an action plan to address the identified water quality concern to
the satisfaction of the Department.
4.19.2 Submit valid and verifiable data and information that are representative of ambient
conditions to demonstrate to the Department that the receiving water or groundwater is
attaining the water quality standard.
4.19.3 Submit an application to the Department for an individual storm water discharge permit.
4.20 Continuation of the Expired General Permit: The Department’s goal is to reissue this general
permit prior to its expiration date. However, in accordance with s. NR 216.09, Wis. Adm. Code, a
permittee shall reapply to the Department at least 180 days prior to the expiration date for continued
coverage under this permit after its expiration. If the permit is not reissued by the time the existing
permit expires, the existing permit remains in effect.
4.21 Need to Halt or Reduce Activity not a Defense: It is not a defense for a permittee in an
enforcement action to claim that it would have been necessary to halt or reduce the permitted activity
in order to maintain compliance with the conditions of the permit.
5. DEFINITIONS USED IN THIS PERMIT
Definitions for some of the terms found in this permit are as follows:
5.1 Department means the Wisconsin Department of Natural Resources.
Page 31 of 59 WPDES Permit No. WI-S050075-3-1
5.2 Development means residential, commercial, industrial and institutional land uses and associated
roads.
5.3 Erosion means the process by which the land’s surface is worn away by the action of wind, water, ice
or gravity.
5.4 Hazardous substance means any substance or combination of substances including any waste of a
solid, semisolid, liquid or gaseous form which may cause or significantly contribute to an increase in
mortality or an increase in serious irreversible or incapacitating reversible illness or which may pose a
substantial present or potential hazard to human health or the environment because of its quantity,
concentration or physical, chemical or infectious characteristics. This term includes, but is not limited to,
substances which are toxic, corrosive, flammable, irritants, strong sensitizers or explosives as
determined by the Department.
5.5 Illicit connection means any man-made conveyance connecting an illicit discharge to a municipal
separate storm sewer system.
5.6 Illicit discharge means any discharge to a municipal separate storm sewer system that is not
composed entirely of storm water except discharges authorized by a WPDES permit or other discharge
not requiring a WPDES permit such as landscape irrigation, individual residential car washing, fire
fighting, diverted stream flows, uncontaminated groundwater infiltration, uncontaminated pumped
groundwater, discharges from potable water sources, foundation drains, air conditioning condensation,
irrigation water, lawn watering, flows from riparian habitats and wetlands, and similar discharges.
However, the occurrence of a discharge listed above may be considered an illicit discharge on a case-by-
case basis if the permittee or the Department identifies it as a significant source of a pollutant to waters
of the state.
5.7 Impaired water means a waterbody impaired in whole or in part and listed by the Department
pursuant to 33 USC § 1313(d)(1)(A) and 40 CFR 130.7, for not meeting a water quality standard,
including a water quality standard for a specific substance or the waterbody's designated use.
5.8 Infiltration means the entry and movement of precipitation or runoff into or through soil.
5.9 Jurisdiction means the area where the permittee has authority to enforce its ordinances or
otherwise has authority to exercise control over a particular activity of concern.
5.10 Land disturbing construction activity means any man-made alteration of the land surface resulting
in a change in the topography or existing vegetative or non-vegetative soil cover that may result in
storm water runoff and lead to increased soil erosion and movement of sediment into waters of the
state. Land disturbing construction activity includes clearing and grubbing, demolition, excavating, pit
trench dewatering, filling and grading activities.
5.11 Maximum Extent Practicable or MEP has the meaning given it in s. NR 151.002(25), Wis. Adm.
Code.
5.12 Major outfall means a municipal separate storm sewer outfall that meets one of the following
criteria:
Page 32 of 59 WPDES Permit No. WI-S050075-3-1
5.12.1 A single pipe with an inside diameter of 36 inches or more, or from an equivalent
conveyance (cross sectional area of 1,018 square inches) which is associated with a drainage
area of more than 50 acres.
5.12.2 A municipal separate storm sewer system that receives storm water runoff from lands
zoned for industrial activity that is associated with a drainage area of more than 2 acres or from
other lands with 2 or more acres of industrial activity, but not land zoned for industrial activity
that does not have any industrial activity present.
5.13 Municipality means any city, town, village, county, county utility district, town sanitary district,
town utility district, school district or metropolitan sewage district or any other public entity created
pursuant to law and having authority to collect, treat or dispose of sewage, industrial wastes, storm
water or other wastes.
5.14 Municipal Separate Storm Sewer System or MS4 means a conveyance or system of conveyances
including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches,
constructed channels or storm drains, which meets all of the following criteria:
5.14.1 Owned or operated by a municipality.
5.14.2 Designed or used for collecting or conveying storm water.
5.14.3 Which is not a combined sewer conveying both sanitary and storm water.
5.14.4 Which is not part of a publicly owned wastewater treatment works that provides
secondary or more stringent treatment.
5.15 New MS4 discharge of pollutants means an MS4 discharge that would first occur after the
permittee’s original date of initial coverage under an MS4 permit to a surface water to which the MS4
did not previously discharge storm water, and does not include an increase in an MS4’s discharge to a
surface water to which the MS4 discharged on or before coverage under this permit.
5.16 Outfall means the point at which storm water is discharged to waters of the state or to a storm
sewer (e.g., leaves one municipality and enters another).
5.17 Permittee means a person who has applied for and received WPDES permit coverage for storm
water discharge. For the purposes of this permit, permittee is the owner or operator of a municipal
separate storm sewer system authorized to discharge storm water into waters of the state.
5.18 Permitted area means the areas of land under the jurisdiction of the permittee that drains into a
municipal separate storm sewer system, which is regulated under a permit issued pursuant to subch. I of
NR 216, Wis. Adm. Code.
5.19 Pollutants of concern means a pollutant that is causing impairment of a waterbody.
5.20 Reach means a specific stream segment, lake or reservoir as identified in a TMDL.
Page 33 of 59 WPDES Permit No. WI-S050075-3-1 5.21 Reachshed means the drainage area contributing runoff to a given reach.
5.22 Redevelopment means areas where development is replacing older development.
5.23 Riparian landowners are the owners of lands bordering lakes and rivers.
5.24 Sediment means settleable solid material that is transported by runoff, suspended within runoff or
deposited by runoff away from its original location.
5.25 Start Date is the date of permit coverage under this permit, which is specified in the Department
letter authorizing coverage.
5.26 Storm water management practice means structural or non-structural measures, practices,
techniques or devices employed to avoid or minimize soil, sediment or pollutants carried in runoff to
waters of the state.
5.27 Storm Water Pollution Prevention Plan or SWPPP refers to the development of a site-specific plan
that describes the measures and controls that will be used to prevent and/or minimize pollution of
storm water.
5.28 Structural storm water management facilities are engineered and constructed systems that are
designed to provide storm water quality control such as wet detention ponds, constructed wetlands,
infiltration basins and grassed swales.
5.29 Total maximum daily load or TMDL means the amount of pollutants specified as a function of one
or more water quality parameters, that can be discharged per day into a water quality limited segment
and still ensure attainment of the applicable water quality standard.
5.30 Urbanized area means a place and the adjacent densely settled surrounding territory that together
have a minimum population of 50,000 people, as determined by the U.S. bureau of the census based on
the latest decennial federal census.
5.31 Waste Load Allocation or WLA means the allocation resulting from the process of distributing or
apportioning the total maximum load to each individual point source discharge.
5.32 Waters of the State has the meaning given it in s. 283.01(20), Wis. Stats.
5.33 WPDES permit means a Wisconsin Pollutant Discharge Elimination System permit issued pursuant
to ch. 283, Wis. Stats.
Page 34 of 59 WPDES Permit No. WI-S050075-3-1 Appendix A: MS4 Permittees Subject to a TMDL Approved Prior to May 1, 2014
including Applicable Updates
A.1 Applicability and Structure of Appendix.
A.1.1 Applicability. In accordance with section 1.5.2.a, this Appendix A applies to permittees subject
to a total maximum daily load (TMDL) approved by the United States Environmental Protection
Agency (USEPA) prior to May 1, 2014, that includes the following:
• “Total Maximum Daily Loads for Total Phosphorus and Total Suspended Solids in the Rock
River Basin,” approved by USEPA September 2011
• “Total Maximum Daily Load and Watershed Management Plan for Total Phosphorus and
Total Suspended Solids in the Lower Fox River Basin and Lower Green Bay,” approved by
USEPA May 2012
• “Lake St. Croix Nutrient Total Maximum Daily Load,” approved by USEPA August 2012
• “Phosphorus Total Maximum Daily Loads (TMDLs) Tainter Lake and Lake Menomin, Dunn
County Wisconsin,” approved by USEPA September 2012
In addition to the TMDLs listed above, Appendix A also applies to the following:
• “Beaver Dam Lake Total Maximum Daily Load for Total Phosphorus,” approved by USEPA
August 2018
Note: The Beaver Dam Lake TMDL updates allocations from the Rock River Basin TMDL for
the City of Beaver Dam and provides higher allocations, lower percent reductions, than
those contained in the Rock River Basin TMDL approved in September 2011.
Note: If the MS4 area extends into or discharges to other basins with a USEPA approved TMDL, a
permittee could be subject to more than one TMDL and thus the requirements under Appendices B
and/or C.
A.1.2 Structure of Appendix. This appendix is structured to provide permittees with several
compliance options. Section A.2 defines full TMDL compliance while sections A.3, A.4, and A.5
provide different compliance options. Section A.3 applies to permittees that submitted a plan
meeting the requirements contained in sections 1.5.4.4 and 1.5.4.5 of WDPES Permit No. WI-
S050075-2 and received Department concurrence regarding the plan. Section A.3 also applies to
permittees that are participating in an approved adaptive management plan. Section A.4 details
requirements for permittees that can comply with the TMDL during this permit term. Section A.5
applies to permittees who have not been able to utilize Sections A.3 or A.4. Section A.5 contains two
compliance tracks; permittees may choose between the requirements stipulated under Section
A.5.2 or meet the requirements under Section A.5.3. Section A.6 outlines reporting requirements.
A.2 Full TMDL Compliance.
A.2.1 USEPA is allowing the Department to evaluate MS4 compliance with TMDL wasteload
allocations using a percent reduction framework consistent with Wisconsin’s storm water
program. For consistency with existing storm water program requirements, demonstration of
Page 35 of 59 WPDES Permit No. WI-S050075-3-1 TMDL compliance will use the percent reduction measured from the no runoff management
controls (no-controls) condition. The percent reduction from no-controls, for each pollutant of
concern and reachshed, necessary to meet the TMDL Wasteload Allocations (WLAs) for the
USEPA approved TMDLs are listed in Tables A1-A4. The no-controls modeling condition means
taking no (zero) credit for existing storm water control measures that reduce the discharge of
pollutants. Existing practices can then be applied and counted toward meeting the TMDL
reductions.
A.2.2 TMDLs may assign a percent reduction for one or more reachsheds for each pollutant of
concern (i.e., total suspended solids and total phosphorus). Full TMDL compliance is achieved by
the permittee provided all of the following conditions are met:
a. By October 31, 2023, the permittee submits the necessary data and documentation
to the Department that demonstrates that the permittee meets the percent reductions
stipulated in Tables A1-A4 for each reachshed that the MS4 discharges to and for each
pollutant of concern.
b. The documentation summitted by the permittee includes the policies, procedures,
and regulatory mechanisms that the permittee will employ to ensure that storm water
controls and management measures will continue to be operated and maintained so
that their pollutant removal efficiency continues to be met.
c. Based upon the data and documentation and any necessary subsequent information
requested by the Department, the permittee receives written concurrence from the
Department by April 30, 2024, that the permittee has achieved full TMDL compliance.
A.3 Implementation of TMDL Compliance Plan or Participation in an Approved Adaptive Management
Plan.
A.3.1 If the permittee submitted a plan meeting the requirements contained in sections 1.5.4.4
and 1.5.4.5 of WDPES Permit No. WI-S050075-2 and has received Department concurrence
regarding the plan, the permittee shall implement the plan.
Note: If the permittee has not received the Department’s concurrence regarding a previously
submitted plan, contact your regional storm water engineer.
A.3.2 In accordance with s. 283.13(7), Wis. Stats., and s. NR 217.18, Wis. Adm. Code, if by the
effective date of this permit the permittee has chosen to participate in an Adaptive
Management project that has been approved by the Department the permittee shall continue
to participate in the implementation of the Adaptive Management project.
A.4 Compliance During the Term of This Permit. If the permittee determines that it can meet the
requirements stipulated in section A.2.2 by October 31, 2023, the permittee shall meet all the following:
A.4.1 By March 31, 2020, the permittee shall notify the Department if compliance will be
achieved by October 31, 2023.
Page 36 of 59 WPDES Permit No. WI-S050075-3-1 A.4.2 Consistent with the reporting requirements contained in section A.6, the permittee shall
submit written verification that it is has met the applicable requirements contained in section
A.2.2.
A.5 Compliance Over Multiple Permit Terms. If the permittee cannot meet the requirements stipulated
under sections A.3 or A.4, the permittee shall demonstrate continued progress towards compliance with
the requirements contained in section A.2.2. During the term of this permit, the following are required:
A.5.1 By March 31, 2020, if the permittee determines that the applicable requirements
contained in section A.2.2 will not be achieved by October 31, 2023, then the permittee shall
notify the Department in writing which reachsheds and pollutants of concern are not in
compliance with the requirements contained in section A.2.2.
A.5.2 By March 31, 2021, the permittee shall submit a written plan to the Department
identifying and describing the actions that the permittee shall undertake, including a proposed
schedule and milestones, to achieve the following by the end of the term of this permit:
a. A minimum of a 20% additional reduction in sediment or total suspended solids.
b. A minimum of a 10% additional reduction in total phosphorus.
Note: The reductions stipulated under A.5.2 are interim compliance targets set for this
permit term. Future permit reduction targets may taper off or vary between
municipalities based on individual plans as it is expected that municipalities will rely
more on reductions obtained through redevelopment.
The percent reductions under A.5.2.a and A.5.2.b are measured from the baseline assumptions
for the TMDLs, which represent compliance with s. NR 151.13, Wis. Adm. Code, to the total
reductions listed in Tables A1-A4 (see example calculation below). The baseline assumption for
the Rock River TMDL is a 40% reduction from no-controls for total suspended solids and a 27%
reduction from no-controls for total phosphorus. For all other TMDLs covered by Appendix A,
the baseline is a 20% reduction from no controls for total suspended solids and a 15% reduction
from no-controls for total phosphorus.
Note: Refer to the applicable TMDL reports for additional discussions on baseline.
Unlike full compliance as outlined in section A.2.2, compliance with the reductions stipulated
under A.5.2.a and A.5.2.b can be achieved utilizing an averaged reduction calculated from
individual reductions achieved in one or multiple reachsheds and spanning the entire MS4 area
that is impacted by the TMDL.
Page 37 of 59 WPDES Permit No. WI-S050075-3-1
Note: Reductions obtained through a permittee’s participation in a water quality trading
project, in accordance with s. 283.84, Wis. Stats., and that has been reviewed and
approved by the Department, may be counted toward credit in meeting the
requirements stipulated under sections A.5.2.a and A.5.2.b. Additional information on
water quality trading is available from the Department’s Internet site at:
https://dnr.wi.gov/topic/surfacewater/waterqualitytrading.html
A.5.3 If the permittee determines by March 31, 2020, that it is unable to achieve the reductions
stipulated under sections A.5.2.a and A.5.2.b, the permittee shall meet the following
requirements by October 31, 2023:
Note: The permittee may optimize deployment of resources between the requirements
listed below to maximize reductions for the least cost. In some cases, permittees may
already be meeting these requirements.
Example: Calculation to meet A.5.2.a for total suspended solids: “Municipality
A” has modeled a no-controls total suspended solid (TSS) load of 100 tons.
Determine Allowable Wasteload Allocation:
“Municipality A” is in the Rock River Basin in Subbasin 3. From Table A.1, the
TMDL requires a 55.6% reduction from no-controls for TSS. This means per
Section A.2, “Municipality A” must ultimately achieve a mass reduction of 55.60
tons (55.6% of 100 tons) resulting in an allowable wasteload allocation of 44.40
tons (100 tons no-controls minus the 55.60 tons reduction).
Determine Baseline:
Baseline for The Rock River TMDL is a 40% reduction in TSS. The no-controls load
for “Municipality A” is 100 tons. Therefore, the baseline load for “Municipality A”
is 60 tons (40% reduction of 100 tons).
Calculate 20% Additional Reduction:
Under A.5.2.a, “Municipality A” must achieve an additional 20% reduction. The
baseline load is 60 tons and the allowable wasteload load is 44.4 tons. The
difference is 15.60 tons (60 tons minus 44.4 tons). An additional 20% reduction
of the remaining 15.6 tons results in “Municipality A” needing to achieve an
additional 3.12 tons in reduction.
Load reduction at the end of permit term:
At the end of the permit term, “Municipality A” should demonstrate a minimum
reduction from no controls of 43.12 tons (40 tons plus 3.13 tons). “Municipality
A” will still require additional reductions over subsequent permit terms to reach
the allowable wasteload allocation of 44.40 tons.
The calculation process is similar for total phosphorus.
Page 38 of 59 WPDES Permit No. WI-S050075-3-1 a. Pursuant to the permittee’s authority under s. 281.33(6)(a)2., Wis. Stats., the
permittee shall create or revise and promulgate a municipal storm water management
ordinance applicable to redevelopment that requires compliance with post-construction
storm water management performance standards that are stricter than the uniform
statewide standards established by the Department. When reporting to the Department
under section A.6.3, the permittee shall include a justification for the level of pollutant
reduction in the ordinance with an assessment of the progress it achieves towards full
compliance with the TMDL. The redevelopment reductions may be adjusted to account
for other storm water controls measures that may exist. The permittee may also
establish total phosphorus reduction levels for redevelopment projects.
Note: The permittee may enact an ordinance that is municipal wide, targets individual
TMDL reachsheds, or designated areas within the permitted MS4 balancing required
TMDL reductions, parcel size, and the impact of other treatment options. It is expected
that under future permit terms as management options have been optimized that most
of the future reductions could be realized through redevelopment activities.
b. The permittee shall create or revise a municipal ordinance that requires the
development and implementation of a maintenance plan for all privately-owned storm
water treatment facilities for which the permittee takes a phosphorus and/or total
suspended solids reduction credit. The permittee shall develop and implement
procedures and measures to verify and track that the storm water treatment facilities
are inspected on a regular schedule and maintained in the intended working condition
in accordance with the plans. The permittee shall require that maintenance agreements
be recorded with the appropriate property records that obligates the current and future
owners to implement the maintenance plans.
c. The permittee shall revise or promulgate a municipal ordinance that requires the
submittal of as-built plans for storm water management facility that the permittee takes
a phosphorus and/or total suspended solids reduction credit. The permittee shall
require submittal of the as-built plans prior to close-out of the local permit or upon final
approval and shall maintain appropriate records and tracking of the plans.
d. If the pollutant of concern is total phosphorus, the permittee shall implement,
expand, or optimize a municipal leaf collection program coupled with street cleaning to
serve areas where municipal leaf collection is not currently provided within the MS4 but
for which a phosphorus reduction has been assigned and additional reductions could be
achieved.
Note: The Department’s “Interim Municipal Phosphorus Reduction Credit for Leaf
Management Programs” guidance document includes recommendations on how the
permittee’s municipal leaf collection program should be designed and implemented.
The guidance is available from the Department’s Internet site at:
https://dnr.wi.gov/topic/stormwater/standards/ms4_modeling.html
e. Within the MS4 permitted area, the permittee shall inventory the condition of the
conveyance systems and outfalls. Where erosion or scour is occurring, the permittee
shall develop a schedule to stabilize the identified areas over a 5-year period.
Page 39 of 59 WPDES Permit No. WI-S050075-3-1
f. The permittee shall install at least one new structural best management practice or
enhance one or more existing structural best management practices to reduce a
pollutant of concern discharged via storm water runoff to an impaired waterbody for
which a WLA has been assigned to the permittee. The permittee shall develop and
implement a maintenance plan for each new structural best management practice.
g. The permittee shall conduct an analysis of the current municipal street cleaning
program, to determine if additional pollutant loading reductions can be achieved. The
permittee shall evaluate optimizing sweeping frequency, targeting of critical areas and
time periods, and instituting parking restrictions. If a pollutant reduction can be
achieved through optimizing the existing street cleaning program, the permittee shall
adopt the optimized program the next calendar year or provide a written explanation to
the Department explaining why the optimize street cleaning program is not feasible and
provide alternative options to achieve similar pollutant reductions.
A.6 Reporting Requirements. For the term of this permit, the permittee shall meet the following
reporting requirements:
A.6.1 Compliance Determination Reporting. The permittee shall submit the information
requested in this appendix in accordance with the following schedule:
a. By March 31, 2020, for sections A.4.1 and A.5.1.
b. By March 31, 2021, for section A.5.2.
c. By October 31, 2023, for sections A.2.2.a and A.5.3.
A.6.2 Annual Reporting. For compliance options outlined under sections A.3, A.4, and A.5, the
permittee shall include a description and the status of progress toward implementing the
identified actions and activities in their MS4 annual reports due by March 31 of each year.
A.6.3 Final Documentation. Except for permittees complying with a Department approved
adaptive management plan under section A.3.2, by October 31, 2023, the permittee shall submit
documentation to the Department to verify that the permittee has completed all actions
required under this appendix including the following:
a. An updated storm sewer system map that identifies:
(1) The current municipal boundary. For a permittee that is not a city or village,
identify the permitted area.
Note: The permitted area for towns, counties and non-traditional MS4s pertains
to the area within an urbanized area or the area served by its storm sewer
system, such as a university campus.
(2) The TMDL reachshed boundaries within the municipal boundary, and the
area of each TMDL reachshed in acres within the municipal boundary.
Page 40 of 59 WPDES Permit No. WI-S050075-3-1
(3) The MS4 drainage boundary associated with each TMDL reachshed, and the
area in acres of the MS4 drainage boundary associated with each TMDL
reachshed.
b. The permittee shall submit an updated tabular summary that includes the following
for each MS4 drainage boundary associated with each TMDL reachshed as identified
under section A.6.3.a and for each pollutant of concern:
(1) The permittee’s percent reduction needed to comply with its TMDL
wasteload allocation from the no-controls modeling condition.
(2) The modeled MS4 annual average pollutant load without any storm water
control measures.
(3) The modeled MS4 annual average pollutant load with existing storm water
control measures.
(4) The percent reduction in pollutant load achieved calculated from the no-
controls condition determined under section A.6.3.a(2) and the existing controls
condition determined under section A.6.3.a(3).
(5) The existing storm water control measures, including the type of measure,
area treated in acres, the pollutant load reduction efficiency, and confirmation
of the permittee’s authority for long-term maintenance of each practice.
c. If the updated tabular summary required under section A.6.3.b shows that the
permittee is not achieving the requirements stipulated in section A.2, the permittee
shall submit an updated written plan to the Department that describes how the
permittee will make progress toward achieving compliance. The TMDL implementation
plan shall include the following information:
(1) A list of management options and an implementation schedule that over the
next permit term achieves, to the maximum extent practicable, an additional
20% reduction in sediment or total suspended solids and an additional 10%
reduction in total phosphorus. The percent reductions shall be applied to the
difference measured from loading conditions at the end of this permit to the
total reductions listed in Tables A1-A4. The reductions can be achieved utilizing
an averaged reduction calculated from individual reductions achieved in one or
multiple reachsheds and spanning the entire MS4 area impacted by a TMDL.
Note: Reductions that occur through stricter redevelopment standards or
through water quality trading can be counted toward meeting the reduction
requirements under this section.
Note: Unlike full compliance as outlined in section A.2.2, interim compliance
under this section can be based on an average reduction measured across the
MS4 area impacted by a TMDL.
Page 41 of 59 WPDES Permit No. WI-S050075-3-1
(2) Recommendations and options with supporting analysis for storm water
control measures that will be installed or implemented in future permit terms to
achieve the requirements, to the maximum extent possible, stipulated in section
A.2.
(3) A proposed schedule for implementation of the recommendations and
options identified under section A.6.3.c(1). The proposed schedule may extend
into future permit terms.
(4) A cost effectiveness analysis for implementation of the recommendations
and options identified under section A.6.3.c(1).
Page 42 of 59 WPDES Permit No. WI-S050075-3-1 Table A1: Rock River Basin TMDL Load Reductions Necessary to Meet TMDL Wasteload Allocations by
TMDL Reachshed
Reachshed
Number
(TMDL
Subbasin) Waterbody Name County
TSS %
Reduction from
No-controls
TP % Reduction
from No-controls
2
South Branch Rock
River
Dodge, Fond du
Lac, Green Lake 40.6 48.2
3
South Branch Rock
River Dodge, Fond du Lac 55.6 86.9
20 Rock River
Dodge, Jefferson,
Washington,
Waukesha 40.0 37.2
21 Rock River
Dodge, Jefferson,
Washington,
Waukesha 40.0 34.3
23 Oconomowoc River
Washington,
Waukesha 46.6 35.8
24 Mason Creek
Dodge,
Washington,
Waukesha 47.2 35.0
25 Oconomowoc River
Jefferson,
Waukesha 59.2 73.7
26 Battle Creek Waukesha 57.4 52.6
27 Oconomowoc River
Jefferson,
Waukesha 40.0 27.0
28 Rock River Dodge, Jefferson 40.0 27.7
29 Rock River Dodge, Jefferson 44.2 64.2
30 Johnson Creek Jefferson 40.0 27.0
33
Mill Creek, Beaver
Dam Lake Columbia, Dodge 45.4 48.2
34 Beaver Dam River Columbia 58.6 86.1
37 Park Creek Columbia 72.4 75.2
39 Shaw Brook Columbia 40.0 27.0
45 Maunesha River Columbia 44.8 36.5
51 Crawfish River Columbia 40.0 37.2
54 Rock River
Columbia, Dodge,
Jefferson 43.6 71.5
55 Bark River Waukesha 65.8 76.6
56 Bark River
Jefferson,
Waukesha 40.0 40.9
Page 43 of 59 WPDES Permit No. WI-S050075-3-1
Reachshed
Number
(TMDL
Subbasin) Waterbody Name County
TSS %
Reduction from
No-controls
TP % Reduction
from No-controls
59
Steel Brook,
Scuppernong River,
Bark River
Jefferson,
Walworth, Rock 49.0 66.4
60 Rock River Jefferson, Rock 40.6 48.2
61 Rock River Dane, Rock 41.2 31.4
62
Pheasant Branch
Creek Dane 82.0 78.1
63 Spring (Dorn) Creek Dane 46.6 37.2
64
Yahara River, Lake
Mendota, Lake
Monona Dane, Columbia 73.0 61.3
65 Nine Springs Creek Dane 67.6 62.8
66
Yahara River, Lake
Waubesa, Lake
Kegonsa Dane 62.2 54.0
67 Yahara River Dane 40.0 27.0
68 Yahara River Dane, Rock 50.8 65.0
69 Yahara River Dane, Rock 52.6 79.6
70 Rock River Rock 40.6 27.7
71 Rock River Rock 58.6 48.2
72 Blackhawk Creek Rock, Walworth 40.0 27.0
73 Blackhawk Creek Rock 69.4 64.2
74 Rock River Rock 52.0 39.4
75 Markham Creek Rock 51.4 38.0
76 Rock River Rock 57.4 81.8
78 Bass Creek Rock 40.0 29.9
79 Rock River Rock 62.2 66.4
80* Turtle Creek Rock, Walworth 55.0 62.8
81 Turtle Creek Rock, Walworth 44.2 41.6
83 Lake Koshkonong
Dane, Jefferson,
Rock 55.0 54.0
Note: *MS4 Reachshed 80 reductions are based on Non-Point Source annual average reductions as
TMDL had not assigned a separate MS4 reduction for MS4s in this reach.
Page 44 of 59 WPDES Permit No. WI-S050075-3-1 Table A2: Lower Fox River Basin and Lower Green Bay TMDL Load Reductions Necessary to Meet
TMDL Wasteload Allocations by TMDL Reachshed
Reachshed Name
(Subbasin)
County Subbasin
ID
TSS % Reduction
from No-controls
TP % Reduction
from No-controls
Lower Green Bay Brown LFS7 &
LFS8
52% 41%
Lower Fox River Main Stem Brown,
Outagamie,
Winnebago
City of Green
Bay(1)
LFM 72%
70.4%(1)
41%
East River Brown,
Calumet
LF01 52% 41%
Baird Creek Brown LF01 52% 41%
Bower Creek Brown LF01 52% 41%
Dutchman Creek Brown LF02 52% 41%
Ashwaubenon Creek Brown LF02 52% 41%
Apple Creek Brown,
Outagamie
LF02 52% 41%
Plum Creek Brown,
Calumet
LF03 52% 41%
Kankapot Creek Calumet,
Outagamie
LF03 52% 41%
Garners Creek Outagamie LF03 60% 69%
Mud Creek Outagamie,
Winnebago
LF04 43% 48%
Neenah Slough Winnebago LF06 52% 41%
Duck Creek Brown,
Outagamie
LF05 52% 41%
Trout Creek Brown LF05 52% 41%
Note: % TSS reduction from No Controls = 20 + [0.80 x (% TSS Control Lower Fox TMDL Report)
% TP reduction from No Controls = 15 + [0.85 x (% TP Control Lower Fox TMDL Report)
(1) Due to the regionalization of Green Bay Packaging with New Water (GBMSD), the TSS WLA of
108,259 pounds allocated to Green Bay Packaging was reassigned to the City of Green Bay MS4. This
results in a change in allocation for the City of Green Bay MS4 from 1,073,228 pounds to 1,181,478
pounds of TSS and a corresponding change in the percent reduction from 72% to 70.4%.
Page 45 of 59 WPDES Permit No. WI-S050075-3-1
Table A3: Lake St. Croix Nutrient TMDL Load Reductions Necessary to Meet TMDL Wasteload
Allocations by TMDL Reachshed
Waterbody Name County WBIC
MS4 TP %
Reduction
from No
Controls
Lake St. Croix St. Croix,
Pierce 2601500 46.0
Table A4: Red Cedar River (Tainter Lake, Menomin Lake) TMDL Load Reductions Necessary to Meet
TMDL Wasteload Allocations by TMDL Reachshed
Waterbody Name County WBIC MS4 TP % Reduction from No
Controlsa
Tainter Lake Dunn 2068000
Lake Menomin Dunn 2065900 39.2
Note: aThe TMDL allocations and necessary reduction are calculated using the 2025 projected MS4 build
out area. The 2025 area modeled in a No Controls condition compared against the WLA written in the
TMDL yields the percent reduction.
𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿2025 𝑁𝑁𝑁𝑁 𝐶𝐶𝑁𝑁𝐶𝐶𝐶𝐶𝐶𝐶𝑁𝑁𝐶𝐶𝐶𝐶−1700 𝑙𝑙𝑙𝑙𝑙𝑙𝑦𝑦𝑦𝑦𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿2025 𝑁𝑁𝑁𝑁 𝐶𝐶𝑁𝑁𝐶𝐶𝐶𝐶𝐶𝐶𝑁𝑁𝐶𝐶𝐶𝐶
Page 46 of 59 WPDES Permit No. WI-S050075-3-1 Appendix B: MS4 Permittees Subject to Milwaukee River Basin TMDL
B.1 Applicability. In accordance with section 1.5.2.b, this Appendix B applies to permittees subject to a
total maximum daily load (TMDL) approved by the United States Environmental Protection Agency
(USEPA) that includes the following:
• “Total Maximum Daily Loads for Total Phosphorus, Total Suspended Solids, and Fecal Coliform
Milwaukee River Basin, Wisconsin,” approved by USEPA March 2018
Note: If the MS4 area extends into or discharges to other basins with a USEPA approved TMDL, a
permittee could be subject to more than one TMDL and thus the requirements under Appendices A
and/or C.
B.2 Full TMDL Compliance for Total Suspended Solids (TSS) and Total Phosphorus (TP) WLAs.
B.2.1 USEPA is allowing the Department to evaluate MS4 compliance with TMDL wasteload
allocations using a percent reduction framework consistent with Wisconsin’s storm water
program. For consistency with existing storm water program requirements, TMDL compliance
will use the percent reduction basis from the no runoff management controls (no-controls)
condition. The percent reduction from no-controls, for TSS and total phosphorus for each
reachshed, necessary to meet the TMDL Wasteload Allocations (WLAs) for the USEPA approved
TMDLs are listed on Table B1. The no-controls modeling condition means taking no (zero) credit
for existing storm water control measures that reduce the discharge of pollutants. Existing
practices can then be applied and counted toward meeting the TMDL reductions.
B.2.2 TMDLs may assign a percent reduction for one or more reachsheds for each pollutant of
concern (i.e., total suspended solids (TSS) and total phosphorus (TP)). Full TMDL compliance is
achieved by the permittee provided all of the following conditions are met:
a. By October 31, 2023, the permittee submits the necessary data and documentation
to the Department that demonstrates that the permittee meets the percent reductions
stipulated in Table B1 for each reachshed that the MS4 discharges to and for each
pollutant of concern.
b. The documentation summitted by the permittee includes the policies, procedures,
and regulatory mechanisms that the permittee ill employ to ensure that storm water
controls and management measures will continue to be operated and maintained so
that their pollutant removal efficiency continues to be met.
c. Based upon the data and documentation and any necessary subsequent information
requested by the Department, the permittee receives written concurrence from the
Department by April 30, 2024, that the permittee has achieved full TMDL compliance.
B.3 Participation in an Approved Adaptive Management Plan for Total Suspended Solids (TSS) and
Total Phosphorus (TP) WLAs. In accordance with s. 283.13(7), Wis. Stats., and s. NR 217.18, Wis. Adm.
Code, if the permittee has chosen to participate in an Adaptive Management project that has been
Page 47 of 59 WPDES Permit No. WI-S050075-3-1 approved by the Department the permittee shall continue to participate in the implementation of the
Adaptive Management project.
Note: Information on adaptive management is available from the Department’s Internet site at:
https://dnr.wi.gov/topic/SurfaceWater/AdaptiveManagement.html
B.4 TMDL Implementation Plan for Total Suspended Solids (TSS) and Total Phosphorus (TP) WLAs. If
the permittee is not participating in a Department approved adaptive management plan as stipulated in
section B.3, the permittee shall perform the following activities:
B.4.1 By March 31, 2020, if the permittee determines that the applicable requirements
contained in section B.2.2 will not be achieved by October 31, 2023. The permittee shall notify
the Department which reachsheds and pollutants of concern are not in compliance with the
requirements contained in section B.2.2.
B.4.2 The permittee shall develop a TMDL implementation plan to meet the requirements
stipulated in section B.2.2 includes the following During the term of this permit, the permittee
shall submit the following documentation:
a. By March 31, 2020, an updated storm sewer system map that identifies:
(1) The current municipal boundary. For a permittee that is not a city or village,
identify the permitted area.
Note: The permitted area for towns, counties and non-traditional MS4s pertains
to the area within an urbanized area or the area served by its storm sewer
system, such as a university campus.
(2) The TMDL reachshed boundaries within the municipal boundary, and the
area of each TMDL reachshed in acres within the municipal boundary.
(3) The MS4 drainage boundary associated with each TMDL reachshed, and the
area in acres of the MS4 drainage boundary associated with each TMDL
reachshed.
(4) Identification of areas on a map and the acreage of those areas within the
municipal boundary that the permittee believes should be excluded from its
analysis to show compliance with the TMDL wasteload allocation. In addition,
the permittee shall provide an explanation of why these areas should not be its
responsibility.
Note: An example of an area within a municipal boundary that may not be
subject to a TMDL wasteload allocation for the permittee is an area that does
not drain through the permittee’s MS4.
(5) Flow paths of storm water through the storm sewer system.
Page 48 of 59 WPDES Permit No. WI-S050075-3-1 (6) The location and associated drainage basin of structural best management
practices the MS4 uses for TSS and TP treatment.
b. By March 31, 2021, the permittee shall submit a tabular summary that includes the
following for each MS4 drainage boundary associated with each TMDL reachshed as
identified under section B.4.2.a(2) and for each pollutant of concern listed in Table B1:
(1) The permittee’s percent reduction needed to comply with its TSS and TP
WLA from the no-controls modeling condition. The no-controls modeling
condition means taking no (zero) credit for storm water control measures that
reduce the discharge of pollutants.
Note: This model run is comparable to the no-controls condition modeled for
the developed urban area performance standard of s. NR 151.13, Wis. Adm.
Code.
(2) The modeled annual average pollutant load without any storm water control
measures for each reachshed which the MS4 discharge to.
(3) The modeled MS4 annual average pollutant load with existing and current
storm water control measures for each reachshed which the MS4 discharges to.
(4) The percent reduction in pollutant load achieved calculated from the no-
controls condition determined under section B.4.2.b(2) and the existing controls
condition determined under section B.4.2.b(3).
(5) The existing storm water control measures including the type of measure,
area treated in acres, the pollutant load reduction efficiency, and confirmation
of the permittee’s authority for long-term maintenance of each practice.
c. By March 31, 2022, if the tabular summary required under section B.4.2.b shows that
the permittee is not achieving the applicable percent reductions needed to comply with
section B.2.2, then the permittee shall submit a written TMDL Implementation Plan to
the Department that describes how the permittee will make progress toward achieving
compliance. The plan shall include the following information:
(1) Recommendations and options for storm water control measures that will
be considered to reduce the discharge of each pollutant of concern. At a
minimum, the following shall be evaluated: all post-construction BMPs for
which the Department has a technical standard, optimizing or retrofitting all
existing public and private storm water control practices, regional practices,
optimization or improvements to existing BMPs, incorporation of storm water
control for all road reconstruction projects, more restrictive post-construction
ordinances, updated development and redevelopment standards.
(2) A proposed schedule for implementation of the alternatives identified under
section B.4.2.c(1). The proposed schedule may extend beyond the expiration
date of this permit. The schedule should aim to achieve, to the maximum extent
Page 49 of 59 WPDES Permit No. WI-S050075-3-1 practicable, a 20% reduction in sediment or total suspended solids and a 10%
reduction in total phosphorus over the next permit term. The percent
reductions shall be applied to the difference measured between the current
loadings to the total reductions listed in Table B1. The reductions can be
achieved utilizing an averaged reduction calculated from individual reductions
achieved in one or multiple reachsheds and spanning the entire MS4 area
impacted by a TMDL.
Note: The reductions stipulated under B.4.2.c(2) are interim compliance targets
set as a planning target for the next permit term. Future permit reduction
targets may tapper off or vary between municipalities based on individual plans
as it is expected that municipalities will rely more on reductions obtained
through redevelopment. In many some cases, reductions that occur through
redevelopment activities as outlined in section B.4.3.a may provide the most
economical and practical method toward eventually achieving the reduction
goals.
(3) A cost effectiveness analysis for implementation of the recommendations
and options identified under section B.4.2.c(1).
Note: The Department has developed the guidance document “TMDL Guidance for MS4
Permits: Planning, Implementation, and Modeling Guidance.” The guidance is available
on the Department’s Internet site:
https://dnr.wi.gov/topic/stormwater/standards/ms4_modeling.html, and is available to
assist a permittee with complying with the requirements of section B.4.
Note: Reductions obtained through a permittee’s participation in a water quality trading
project, in accordance with s. 283.84, Wis. Stats., and that has been reviewed and
approved by the Department, can be counted toward credit in meeting the
requirements stipulated under section B.4.2.c(2). Additional information on water
quality trading is available from the Department’s Internet site at:
https://dnr.wi.gov/topic/surfacewater/waterqualitytrading.html
B.4.3 TMDL Compliance During the Term of This Permit for Total Suspended Solids (TSS) and
Total Phosphorus (TP) WLAs. In addition to the planning requirements contained in section
B.4.2, during the term of this permit the permittee shall select and implement a minimum of
three of the activities listed below:
Note: The permittee may optimize deployment of resources between the requirements
listed below to maximize reductions for the least cost. In some cases, permittees may
already be meeting these requirements.
a. Pursuant to the permittee’s authority under s. 281.33(6)(a)2., Wis. Stats., the
permittee shall create or revise and promulgate a municipal storm water management
ordinance applicable to redevelopment that requires compliance with post-construction
storm water management performance standards that are stricter than the uniform
statewide standards established by the Department. When reporting to the Department
under section B.6.3, the permittee shall include a justification for the level of pollutant
Page 50 of 59 WPDES Permit No. WI-S050075-3-1 reduction in the ordinance with an assessment of the progress it achieves towards full
compliance with the TMDL. The redevelopment TSS reduction may be adjusted to
account for other storm water controls measures that may exist. The permittee may
also establish TP reduction levels for redevelopment projects.
Note: The permittee may enact an ordinance that is municipal wide, targets individual
TMDL reachsheds, or designated areas within the permitted MS4 balancing required
TMDL reductions, parcel size, and the impact of other treatment options. It is expected
that under future permit terms as management options have been optimized that most
of the future reductions could be realized through redevelopment activities.
b. The permittee shall create or revise a municipal ordinance that requires the
development and implementation of a maintenance plan for all privately-owned storm
water treatment facilities for which the permittee takes a phosphorus and/or total
suspended solids reduction credit. The permittee shall develop and implement
procedures and measures to verify and track that the storm water treatment facilities
are inspected on a regular schedule and maintained in the intended working condition
in accordance with the plans. The permittee shall require that maintenance agreements
be recorded with the appropriate property records that obligates the current and future
owners to implement the maintenance plans.
c. The permittee shall revise or promulgate a municipal ordinance that requires the
submittal of as-built plans for which the permittee takes a phosphorus and/or total
suspended solids reduction credit. The permittee shall require submittal of the as-built
plans prior to close-out of the local permit or upon final approval and shall maintain
appropriate records and tracking of the plans.
d. If the pollutant of concern is total phosphorus, implement, expand, or optimize a
municipal leaf collection program coupled with street cleaning to serve areas where
municipal leaf collection is not currently provided within the MS4 but for which a
phosphorus WLA has been assigned and additional reductions could be achieved.
Note: The Department’s “Interim Municipal Phosphorus Reduction Credit for Leaf
Management Programs” guidance document includes recommendations on how the
permittee’s municipal leaf collection program should be designed and implemented.
The guidance is available from the Department’s Internet site at:
https://dnr.wi.gov/topic/stormwater/standards/ms4_modeling.html
e. Within the MS4 permitted area, the permittee shall inventory the condition of the
conveyance systems and outfalls. Where erosion or scour is occurring, the permittee
shall develop a schedule to stabilize the identified areas.
f. Install at least one new structural best management practice or enhance one or more
existing structural best management practices to reduce a pollutant of concern
discharged via storm water runoff to an impaired waterbody for which a WLA has been
assigned to the permittee. The permittee shall develop and implement a maintenance
plan for each new structural best management practice.
Page 51 of 59 WPDES Permit No. WI-S050075-3-1 g. Permittee shall conduct an analysis of the current municipal street cleaning program,
to determine if additional pollutant loading reductions can be achieved. The permittee
shall evaluate optimizing sweeping frequency, targeting of critical areas and time
periods, and instituting parking restrictions. If a pollutant reduction can be achieved
through optimizing the existing street cleaning program, the permittee shall adopt the
optimized program the next calendar year or provide a written explanation to the
Department explaining why the optimize street cleaning program is not feasible and
provide alternative options to achieve similar pollutant reductions.
Note: The permittee may optimize deployment of resources between the requirements
listed above to maximize reductions for the least cost; for example, only increase street
sweeping where structural practices do not already exist to treat the runoff for the area.
B.5 TMDL Compliance and Implementation for Bacteria WLAs. This section applies to all permittees
with a bacteria WLA specified in the Milwaukee River Basin TMDL Final Report dated March 19, 2018.
The permittee shall do all of the following:
B.5.1 As part of its program to address illicit discharges under section 2.3 of this permit, by
March 31, 2021, the permittee shall begin to conduct ongoing public education and outreach
activities specifically to increase awareness of bacterial pollution problems, potential sources,
proper pet waste management, and the impacts of urban wildlife and pests.
B.5.2 In addition to complying with the requirements in section 2.3 of this permit, by March 31,
2022, the permittee shall develop and submit to the Department a bacteria source identification
and elimination plan. The permittee shall identify in the plan each potential source of fecal
coliform and E. coli entering its MS4. As part of the plan. the permittee shall develop a strategy,
including design, cost estimates, sources of funding, and a schedule to eliminate the identified
sources.
Note: While the TMDL allocations in the Milwaukee River Basin TMDL are expressed only in
terms of fecal coliform, enteric pathogens such as fecal coliform and E. coli are the cause of the
impairments that the TMDL intends to address. Management practices, such as elimination of
Illicit connections and leaking sewers, will address both fecal coliform and E. coli.
B.5.3 By March 31, 2023, the permittee shall adopt local ordinances to address the
requirements for proper pet waste management, the restrictions on feeding of urban wildlife
that are potential sources of bacteria entering the MS4, the requirements for property owners
to cooperate with identifying and eliminating illicit sanitary sewerage cross-connections with the
MS4, and the requirements for property owners to address other potential sources of bacteria
that may enter the MS4 (e.g., refuse management, pest control).
B.6 Reporting Requirements. For the term of this permit, the permittee shall meet the following
reporting requirements:
B.6.1 Compliance Determination Reporting. The permittee shall submit the information
requested in this appendix in accordance with the following schedule:
a. By March 31, 2020, for section B.4.1 and B.4.2.a.
Page 52 of 59 WPDES Permit No. WI-S050075-3-1 b. By March 31, 2021, for sections B.4.2.b and B.5.1.
c. By March 31, 2022, for sections B.4.1.c and B.5.2.
d. By March 31, 2023, for section B.5.3.
e. By October 31, 2023, for section B.2.2.a.
B.6.2 Annual Reporting. For requirements outlined under sections B.3, B.4, and B.5 the
permittee shall include a description and the status of progress toward implementing the
identified actions and activities in their MS4 annual reports due by March 31 of each year.
B.6.3 Final Documentation. By October 31, 2023, the permittee shall submit documentation to
the Department to verify that the permittee has completed all actions required under this
appendix including submittal of the TMDL implementation plan required under section B.4 and
documentation that the three activities selected under section B.4.3 have been completed.
Page 53 of 59 WPDES Permit No. WI-S050075-3-1
Table B1: Milwaukee River Basin TMDL Load Reductions Necessary to Meet TMDL Wasteload
Allocations by TMDL Reachshed
Kinnickinnic River Basin:
Reachshed
(TMDL
Subbasin) Waterbody Name Waterbody Extents
TSS % Reduction
from No-controls
TP % Reduction
from No-controls
KK-1 Lyons Park Creek Entire Length 78.4% 68.1%
KK-2 Kinnickinnic River
From Wilson Park Creek to
Lyons Park Creek 77.6% 68.1%
KK-3 South 43rd St. Ditch Entire Length 76.8% 78.7%
KK-4
Edgerton Channel,
Wilson Park Creek, Villa
Mann Creek Entire Length 84.0% 89.4%
KK-5 Holmes Avenue Creek Entire Length 80.0% 78.7%
KK-6 Cherokee Park Creek Entire Length 77.6% 69.0%
KK-7 Kinnickinnic River Estuary to Wilson Park Creek 75.2% 45.0%
Menomonee River Basin:
Reachshed
(TMDL
Subbasin) Waterbody Name Waterbody Extents
TSS % Reduction
from No-controls
TP % Reduction
from No-controls
MN-1 Menomonee River
From Nor-X-Way Channel to
Headwaters 66.4% 63.6%
MN-2 Goldendale Creek Entire Length 63.2% 47.7%
MN-3
West Branch
Menomonee River Entire Length 65.6% 60.1%
MN-4 Willow Creek Entire Length 64.0% 51.2%
MN-5 Nor-X-Way Channel Entire Length 70.4% 72.5%
MN-6
Menomonee River and
Dretzka Park Creek
From Little Menomonee River
to Nor-X-Way Channel 73.6% 69.0%
MN-7 Lilly Creek Entire Length 70.4% 64.5%
MN-8 Butler Ditch Entire Length 69.6% 58.3%
MN-9 Little Menomonee River Entire Length 70.4% 64.5%
MN-10 Menomonee River
From Underwood Creek to
Little Menomonee River 67.2% 31.7%
MN-11
Underwood Creek and
Dousman Ditch
From South Branch
Underwood Creek to
Headwaters 72.0% 62.7%
Page 54 of 59 WPDES Permit No. WI-S050075-3-1
Reachshed
(TMDL
Subbasin) Waterbody Name Waterbody Extents
TSS % Reduction
from No-controls
TP % Reduction
from No-controls
MN-12 Underwood Creek
From Menomonee River to
South Branch Underwood
Creek 80.0% 76.1%
MN-13
South Branch
Underwood Creek Entire Length 76.8% 69.8%
MN-14 Menomonee River
From Honey Creek to
Underwood Creek 64.8% 49.4%
MN-15 Honey Creek Entire Length 73.6% 67.2%
MN-16 Menomonee River From Estuary to Honey Creek 72.0% 49.4%
Milwaukee River Basin:
Reachshed
(TMDL
Subbasin) Waterbody Name Waterbody Extents
TSS % Reduction
from No-controls
TP % Reduction
from No-controls
MI-1 Upper Milwaukee River
From Campbellsport to
Headwaters ** **
MI-2 Upper Milwaukee River
From Kewaskum To
Campbellsport and Auburn 73.6% 71.6%
MI-3
West Branch
Milwaukee River Entire Length 77.6% 48.6%
MI-4 Kewaskum Creek Entire Length 76.8% 55.7%
MI-5
Watercress Creek and
East Branch Milwaukee
River Entire Length 73.6% 51.2%
MI-6
Quass Creek and
Milwaukee River Near West Bend 73.6% 86.7%
MI-7
Myra Creek and
Milwaukee River
From North Branch
Milwaukee River to West
Bend 79.2% 67.2%
MI-8
North Branch
Milwaukee River
from Adell Tributary to
Headwaters ** **
MI-9 Adell Tributary Entire Length ** **
MI-10
Chambers Creek,
Batabia Creek, and
North Branch
Milwaukee River Near Sherman ** **
MI-11 Melius Creek Entire Length ** **
MI-12 Mink Creek Entire Length ** **
Page 55 of 59 WPDES Permit No. WI-S050075-3-1
Reachshed
(TMDL
Subbasin) Waterbody Name Waterbody Extents
TSS % Reduction
from No-controls
TP % Reduction
from No-controls
MI-13
Stony Creek, Wallace
Creek, and North
Branch Milwaukee
River Near Farmington 74.4% 46.8%
MI-14 Silver Creek Entire Length ** **
MI-15 Milwaukee River Near Fredonia ** **
MI-16 Milwaukee River Near Saukville 75.2% 77.8%
MI-17 Milwaukee River From Cedar Creek to Saukville 76.0% 83.1%
MI-18 Cedar Creek
From Jackson Creek to
Headwaters 76.8% 71.6%
MI-19 Lehner Creek Entire Length 77.6% 61.0%
MI-20 Jackson Creek Entire Length 80.8% 77.8%
MI-21 Little Cedar Creek Entire Length 80.8% 77.8%
MI-22 Cedar Creek Near Jackson 76.8% 54.8%
MI-23 Evergreen Creek Near Jackson 79.2% 53.0%
MI-24
North Branch Cedar
Creek and Cedar Creek
From Milwaukee River to
Myra Creek 73.6% 79.6%
MI-25 Milwaukee River
From Pigeon Creek to Cedar
Creek 81.6% 43.2%
MI-26 Pigeon Creek Entire Length 90.4% 88.5%
MI-27 Milwaukee River
From Lincoln Creek to Pigeon
Creek 72.8% 53.9%
MI-28 Beaver Creek Entire Length 72.8% 88.5%
MI-29 South Branch Creek Entire Length 71.2% 87.6%
MI-30 Indian Creek Entire Length 65.6% 76.1%
MI-31 Lincoln Creek Entire Length 71.2% 85.8%
MI-32 Milwaukee River From Estuary to Lincoln Creek 58.4% 23.7%
Note: **The TMDL did not assign a percent reduction for these reachsheds because modeling indicated
that there is no direct MS4 discharge to this subbasin. If more detailed analysis conducted by the
permittee indicates the presence of an MS4 discharge, contact your DNR storm water engineer or
specialist for more information on how best to proceed.
Page 56 of 59 WPDES Permit No. WI-S050075-3-1 Appendix C: MS4 Permittees Subject to a TMDL Approved After May 1, 2019
C.1 Applicability. In accordance with section 1.5.1.c, this Appendix C applies to permittees subject to a
Department and USEPA TMDL approved after May 1, 2019.
Note: If the MS4 area extends into or discharges to other basins with a USEPA approved TMDL, a
permittee could be subject to more than one TMDL and thus the requirements under Appendices A
and/or B.
C.2 Full TMDL Compliance.
C.2.1 USEPA is allowing the Department to evaluate MS4 compliance with TMDL wasteload
allocations using a percent reduction framework consistent with Wisconsin’s storm water
program. For consistency with existing storm water program requirements, TMDL compliance
will use the percent reduction measured from the no runoff management controls (no-controls)
condition. The percent reduction from no-controls, for each pollutant of concern and reachshed,
necessary to meet the TMDL Wasteload Allocations (WLAs) for the USEPA approved TMDLs are
listed in the approved TMDLs. The no-controls modeling condition means taking no (zero) credit
for existing storm water control measures that reduce the discharge of pollutants. Existing
practices can then be applied and counted toward meeting the TMDL reduction reductions.
C.2.2 TMDLs may assign a percent reduction for one or more reachsheds for each pollutant of
concern (i.e., total suspended solids and total phosphorus). Full TMDL compliance is achieved by
the permittee provided all of the following conditions are met:
a. The permittee submits the necessary data and documentation to the Department
that demonstrates that the permittee meets the percent reductions stipulated in the
USEPA approved TMDL for each reachshed that the MS4 discharges to and for each
pollutant of concern.
b. The documentation summitted by the permittee includes the policies, procedures,
and regulatory mechanisms that the permittee ill employ to ensure that storm water
controls and management measures will continue to be operated and maintained so
that their pollutant removal efficiency continues to be met.
c. Based upon the data and documentation and any necessary subsequent information
requested by the Department, the permittee receives written concurrence from the
Department that the permittee has achieved full TMDL compliance.
C.3 Participation in an approved Adaptive Management Plan. In accordance with s. 283.13(7), Wis.
Stats., and s. NR 217.18, Wis. Adm. Code, if the permittee has chosen to participate in an Adaptive
Management project that has been approved by the Department the permittee shall continue to
participate in the implementation of the Adaptive Management project.
Note: Information on adaptive management is available from the Department’s Internet site at:
https://dnr.wi.gov/topic/SurfaceWater/AdaptiveManagement.html
Page 57 of 59 WPDES Permit No. WI-S050075-3-1
C.4 TMDL Implementation Plan. If the permittee is not participating in a Department approved adaptive
management plan as stipulated in section C.3, a permittee with MS4s discharging to TMDL reachsheds
shall do all the following to demonstrate progress towards achieving the TMDL reductions stipulated in
section C.2.2 and shall submit the following documentation:
C.4.1 Within 12 months of the approval date of the TMDL, an updated storm sewer system map
that identifies:
a. The current municipal boundary. For a permittee that is not a city or village, identify
the permitted area.
Note: The permitted area for towns, counties and non-traditional MS4s pertains to the
area within an urbanized area or the area served by its storm sewer system, such as a
university campus.
b. The TMDL reachshed boundaries within the municipal boundary, and the area of each
TMDL reachshed in acres within the municipal boundary.
c. The MS4 drainage boundary associated with each TMDL reachshed, and the area in
acres of the MS4 drainage boundary associated with each TMDL reachshed.
d. Identification of areas on a map and the acreage of those areas within the municipal
boundary that the permittee believes should be excluded from its analysis to show
compliance with the TMDL WLA. In addition, the permittee shall provide an explanation
of why these areas should not be its responsibility.
Note: An example of an area within a municipal boundary that may not be subject to a
TMDL WLA for the permittee is an area that does not drain through the permittee’s
MS4.
e. Flow paths of storm water through the storm sewer system.
f. The location and associated drainage basin of structural best management practices
the MS4 uses for TSS and TP treatment.
C.4.2 Within 36 months of the approval date of the TMDL, the permittee shall submit a tabular
summary that includes the following for each MS4 drainage boundary associated with each
TMDL reachshed as identified under section C.4.1 and for each TMDL WLA:
a. The permittee’s percent reduction needed to comply with its TMDL WLA from the no-
controls modeling condition. The no-controls modeling condition means taking no (zero)
credit for storm water control measures that reduce the discharge of pollutants.
b. The modeled annual average pollutant load without any storm water control
measures for each subbasin which the MS4 discharges to as previously identified in
section C.4.1.
Page 58 of 59 WPDES Permit No. WI-S050075-3-1 c. The modeled annual average pollutant load with existing storm water control
measures for each subbasin with the MS4 discharges to as previously identified in
section C.4.1.
d. The percent reduction in pollutant load achieved from the no-controls condition and
the existing controls condition.
e. The existing storm water control measures including the type of measure, area
treated in acres, the pollutant load reduction efficiency, and documentation of the
permittee’s authority for long-term maintenance of each practice.
f. If applicable, the remaining pollutant load reduction for each pollutant of concern and
reachshed to meet the TMDL reduction goals.
C.4.3 Within 48 months of the approval date of the TMDL, if the tabular summary required
under section C.4.2 shows that the permittee is not achieving the applicable percent reductions
needed to comply with its TMDL WLA for each TMDL reachshed, then the permittee shall submit
a written TMDL Implementation Plan to the Department that describes how the permittee will
make progress toward achieving compliance with the TMDL WLA. The plan shall include the
following information:
a. Recommendations and options for storm water control measures that will be
considered to reduce the discharge of each pollutant of concern. At a minimum, the
following shall be evaluated: all post-construction BMPs for which the Department has a
technical standard, optimizing or retrofitting all existing public and private storm water
control practices, regional practices, optimization or improvements to existing BMPs,
incorporation of storm water control for all road reconstruction projects, more
restrictive post-construction ordinances, updated development and redevelopment
standards. Focus should be placed on those areas identified in section C.4.2 without any
controls.
b. A proposed schedule for implementation of the alternatives identified under section
C.4.3.a. The proposed schedule may extend beyond the expiration date of this permit.
The schedule should aim to achieve, to the maximum extent practicable, a 20%
reduction in sediment or total suspended solids and a 10% reduction in total
phosphorus over the next permit term. The percent reductions shall be applied to the
difference measured between the current loadings to the total reductions listed in the
TMDL. The reductions can be achieved utilizing an averaged reduction calculated from
individual reductions achieved in one or multiple reachsheds and spanning the entire
MS4 area impacted by a TMDL.
Note: The reductions stipulated under C.4.3.b are interim compliance targets set as a
planning target for the next permit term. Future permit reduction targets may tapper
off or vary between municipalities based on individual plans as it is expected that
municipalities will rely more on reductions obtained through redevelopment. In many
some cases, reductions that occur through redevelopment activities as outlined in
section C.4.3.d may provide the most economical and practical method toward
eventually achieving the reduction goals.
Page 59 of 59 WPDES Permit No. WI-S050075-3-1
c. A cost effectiveness analysis for implementation of the recommendations and options
identified under section C.4.4.a.
Note: The Department has developed the guidance document “TMDL Guidance for MS4
Permits: Planning, Implementation, and Modeling Guidance.” The guidance is available
on the Department’s Internet site:
https://dnr.wi.gov/topic/stormwater/standards/ms4_modeling.html, and is available to
assist a permittee with complying with the requirements of section C.4.
Note: Reductions obtained through a permittee’s participation in a water quality trading
project, in accordance with s. 283.84, Wis. Stats., and that has been reviewed and
approved by the Department, can be counted toward credit in meeting the
requirements stipulated under section C.2.2. Additional information on water quality
trading is available from the Department’s Internet site at:
https://dnr.wi.gov/topic/surfacewater/waterqualitytrading.html
C.5 Annual Reporting. For requirements outlined under sections C.3 and C.4 the permittee shall include
a description and the status of progress toward implementing the identified actions and activities in
their MS4 annual reports due by March 31 of each year.
1
BUREAU OF WATERSHED MANAGEMANT
PROGRAM GUIDANCE
Watershed Management Team
Storm Water Runoff Program
Wisconsin Department of Natural Resources
101 S. Webster Street, P.O. Box 7921
Madison, WI 53707-7921
Modeling Post-Construction Storm Water
Management Treatment
Updated February 2020
EGAD #: 3800-2020-01
WT-19-0023
This document is intended solely as guidance and does not contain any mandatory requirements except where
requirements found in statute or administrative rule are referenced. Any regulatory decisions made by the Department
of Natural Resources in any matter addressed by this guidance will be made by applying the governing statutes and
administrative rules to the relevant facts.
________________________________________________________________________
2
3
A. Statement of Problem Being Addressed
This document is intended to clarify how to model post-construction stormwater management
treatment to comply with the post-construction performance standards of subchs. III (Non-
Agricultural) and IV (Transportation) of ch. NR 151, Wis. Adm. Code. Modeling is not required,
as compliance may also be demonstrated through hand calculations and or in combination with
DNR technical standards developed under subch. V, of ch. NR 151, Wis. Adm. Code. However,
given the efficiency of models, they are commonly used to estimate runoff volumes and rates,
treatment efficiency, infiltration rates and volumes, etc. Each model has certain assumptions and
or limitations that need to be accounted for in order for the treatment practice to achieve the
model’s predicted treatment efficiency. Accounting for such issues might be through treatment
design and or adjustment to the model’s pollutant removal assumptions.
The DNR’s Runoff Management staff recognize the methods set forth in this document as
appropriate for meeting modeling requirements in applicable parts of ss. NR 151.121-128 or ss.
NR 151.241-249, Wis. Adm. Code. However, the procedures in this document are not mandatory,
as other modeling approaches may also be used to satisfy these requirements, so long as they
meet the applicable requirements in ch. NR 151, Wis. Adm. Code, and related regulatory
standards.
This guidance also applies to modeling Municipal Separate Storm Sewer Systems (MS4s) to
show compliance with the developed urban area standard under s. NR 151.13, Wis. Adm. Code,
and Total Maximum Daily Load (TMDL) requirements for Total Suspended Solids (TSS) and
Total Phosphorus (TP). Additional MS4 modeling guidance documents are available via:
http://dnr.wi.gov/topic/stormwater/standards/ms4_modeling.html
Additionally, there are references to Technical Standards and related formal documents
throughout this guidance. These are references to the formal technical standards developed under
subch. V, of ch. NR 151, Wis. Adm. Code. This information is generally available at:
http://dnr.wi.gov/topic/stormwater/standards/postconst_standards.html
Please contact DNR Storm Water Program staff, if you are unable to locate or need assistance
with interpretation of a Technical Standard.
B. Guidance
Model Versions & Model Specific Issues
1. Pervious area soil type is generally based on the NRCS mapped soil layer unless site-specific
conditions dictate otherwise. In WinSLAMM, Type A soils are considered sandy soils, type
B soils are considered silty soils, and type C and D soils are considered clayey soils.
2. As noted under s. NR 151.122 (3), Wis. Adm. Code, use the most current model version of
WinSLAMM or P8. Benefits of this include: (1) older versions of WinSLAMM do not have
as many model warnings to notify a user about model limitations, (2) newer versions may
provide more options to appropriately model treatment and (3) new versions may provide
additional treatment credit. The DNR storm water runoff modeling web page for
WinSLAMM and P8 is: http://dnr.wi.gov/topic/stormwater/standards/slamm.html
3. WinSLAMM 9.4 and earlier versions of WinSLAMM result in double counting of pollutant
removal for most treatment practices modeled in series. This will result in impermissible
overestimation of pollutant removal for modeling treatment practices. Beginning with version
4
9.2, warnings were added to WinSLAMM to help alert modelers of this issue. The modeler
will need to make adjustments to ensure that the results do not include double credit for
removal of the same particle size. PV & Associates has created a document titled ‘Modeling
Practices in Series Using WinSLAMM’ which helps guide users on how certain practices can
be modeled in series. The document is available at:
http://winslamm.com/Select_documentation.html
Note: This is being offered only for informational purposes so that you may find this
information and is not an endorsement of PV & Associates or its products or services.
4. In WinSLAMM, when modeling a wet pond, if the “Initial Stage Elevation” is not changed
from “0” to the outlet elevation, the model starts running with an empty pond. This must be
changed as an empty pond does not represent a wet pond condition. Therefore, the “Initial
Stage Elevation” of a wet pond must be set equal to the invert elevation of the lowest outlet.
5. WinSLAMM version 10.3.2 will give some credit for a “dry pond” or extended detention
pond, which will be considerably less than a pond with a 3-foot deep permanent pool. A dry
pond may be modeled using a ‘wet detention device’ by entering the bottom area of the pond
at stage 0.01 feet. The DNR will allow credit to be taken at the level calculated in
WinSLAMM with the following conditions:
a) Inlet energy dissipation to prevent energy from entering main basin using baffles,
plunge pool, stone weeper, gabion and/or similar functioning structure. A rip rap
apron alone is generally not adequate except for small inlet pipes such as 6” diameter.
b) A stone weeper, gabion, or similar structure is placed around the primary outlet to
help limit sediment from reaching the outlet.
c) No low flow “pilot” channel.
d) Basin shall be vegetated, and vegetation shall be maintained in good condition.
e) Maximum water surface water elevation rise in the pond should not exceed 5 feet for
the 1-yr, 24 hr. rainfall event.
f) Basin should be designed to draw down within 24 hours for the 1-yr, 24 hr. rainfall
event.
6. P8 does not account for scour or sediment resuspension for any of its modeled treatment
devices and this is identified within the P8 help menu, model limitation section. Ponds need
to be designed to prevent resuspension to obtain the efficiency predicted by P8. DNR
recommends that a 3-foot minimum permanent pool depth be maintained over the sediment
storage area to help prevent sediment resuspension. The DNR allows using a straight-line
depreciation such that a pond with a 1.5-foot deep permanent pool would be eligible for 1/2
the pollutant removal efficiency that would be credited due to settling. The sediment storage
depth should not count toward the permanent pool depth.
7. P8 gives pollutant removal credit for swales via infiltration and settling without accounting
for sediment resuspension or scour. Swales are prone to scour and resuspension, which needs
to be accounted for. DNR accepts the approach used in WinSLAMM to not give credit for
trapping of particles smaller than 50 microns, without infiltration. WinSLAMM gives credit
for trapping of sediment equivalent to the volume infiltrated plus removal of particles greater
than 50 microns in runoff that drains through the swale. Based on the National Urban Runoff
Program (NURP) particle size distribution, only about 16% of the particles (by mass) are
larger than 50 microns. Whereas, about 11% of the Total Phosphorus (TP) is associated with
the 16% of sediment (or TSS). If there were no infiltration, the maximum trapping efficiency
for a grass swale would be about 16% of TSS and 11% of TP.
5
Example: If a swale achieves infiltration of 40% of the annual average runoff volume and
achieves 16% particle entrapment for the remaining runoff volume, then the total TSS and TP
removal credit would be calculated as follows:
Fraction infiltrated + 0.16 x fraction not infiltrated = TSS removal
0.40 + [0.16 x (1 - 0.40)] = 0.496 or 49.6%
Fraction infiltrated + 0.11 x fraction not infiltrated = TP removal
0.40 + [0.11 x (1 - 0.40)] = 0.466 or 46.6%
When taking credit for both infiltration and settlement in a swale, P8 can be run with the
Particle Removal Scale Factor” set to zero in the swale device dialog box to obtain the TSS
and TP remaining following swale treatment by infiltration only. The additional credit for
settlement can be calculated by multiplying the TSS annual load remaining by the percent
which is settled, such as 16% for TSS and 11% for TP. Subtract the settlement credit
calculated from the TSS and TP load remaining to get the revised TSS and TP load remaining
and adjust the percent removal accordingly. Note that additional credit for settlement may not
be taken if the swale discharges to another treatment device which would result in double
counting of particles removed.
8. P8 starts its model runs without an existing pollutant concentration in the storm water
management system. P8 needs to be started long enough for the entire storm water system to
be flushed and starting P8 a month early may not be adequate. To be safe, DNR recommends
that P8 be started an extra year before the “keep dates”.
9. A device, which may not be eligible for pollutant removal credit, may still be modeled if it is
in series with other practices because of its benefit on runoff storage (detention) capacity,
which may enhance the treatment efficiency of downgradient treatment devices (e.g., a dry
detention pond upstream of a wet detention pond). Turn off the treatment efficiency of such
practices in P8.
10. Models used to determine the pollutant removal efficiency of wet ponds can also be used for
underground settling tanks (e.g., vaults, pipes or chambers). However, unlike typical wet
ponds, the treatment surface area of circular pipes and arched chambers decreases as depth
increases. For models that are not capable of directly evaluating this condition, an equivalent
pipe/chamber width should be determined and multiplied by the pipe/chamber length to
determine the treatment surface area (see figure 1). The calculated treatment surface area
should be used for each stage above the permanent pool elevation.
A sediment storage depth should be specified for underground settling tanks. The depth
between the bottom of the tank and the invert of the lowest outlet should be 3 feet plus the
sediment storage depth (e.g., 3-ft + 0.5-ft sediment storage = 3.5-ft). If a model that considers
particle resuspension is used (e.g., WinSLAMM), the depth between the top of the sediment
storage and invert of the lowest outlet can potentially be less than 3 feet. The sediment
storage depth indicated in the storm water management plan and/or used in modeling should
be consistent with the sediment removal criteria specified in the long-term maintenance plan.
The system should be designed such that water elevation during any event does not reach the
top of the underground settling tank. Design should include appropriately-spaced cleanouts
for maintenance.
6
Figure 1 (Determining the Equivalent Treatment Surface Area for Underground Settling
with Circular Cross-Section)
Where appropriate, leakage from underground settling tank joints should be minimized to protect
groundwater (e.g., locations where a Type A or B wet pond liner would be used (see DNR Wet
Pond Technical Standard 1001 – Appendix D).
Note: Underground subsurface detention in most cases is an extension of a storm piping system.
The Department of Safety and Professional Services (DSPS) regulates storm systems under its
plumbing code in areas outside of the public right of way. Storm systems are to have watertight
joints and connections pursuant to ss. SPS 382.21(1)(a)2.b. and 384.40(1)(a), Wis. Adm. Code.
DSPS may allow leakage or infiltration from storm plumbing based on its review of a satisfactory
soil report pursuant to s. NR 382.365, Wis. Adm. Code.
11. TSS Calculation
The Total Suspended Solids (TSS) standard for new development and redevelopment requires
control of TSS originating from the post-construction site (new development) or certain
source areas of the post-construction site (redevelopment). Control of TSS from runoff that
originates off-site generally does not count toward meeting the standard. For a redevelopment
site, TSS control credit is to be taken for runoff from parking lot and roadway areas being
redeveloped but DNR allows credit for treatment of runoff from other parking and roadway
areas that are owned by the permittee. As identified in s. NR 151.122 (4), Wis. Adm. Code,
runoff draining to a treatment device from off−site shall be taken into account in determining
7
the treatment efficiency of the practice. Any impact on the efficiency shall be compensated
for by increasing the size of the treatment practice accordingly. The pollutant load from off-
site can be “turned off” but the runoff volume at full build-out needs to be accounted for in
calculating the treatment efficiency of the device. To minimize the size of a treatment device,
it is beneficial to keep runoff that requires treatment segregated from other runoff until after it
has been treated.
WinSLAMM v 10.4.0 and subsequent versions, allow the ‘Other Control Device’ to be used
to either give treatment credit or to remove pollutant loading via a toggle under ‘Tools -
Program Options’. The multiple WinSLAMM run method discussed below generally is not
necessary where this issue is properly accounted for in WinSLAMM v 10.4.0 and subsequent
versions.
To account for additional runoff from an area where the off-site pollutant load is to be
removed from the model, multiple WinSLAMM model runs may be used. It is also possible
to use one WinSLAMM model run along with some hand calculations to show that adequate
mass from on-site areas have been controlled. The following method requires three model
runs to account for this:
a) First, model run (A) is used to establish the TSS load generated from on-site areas
without modeling any treatment practices (do not include any swales/drainage control).
b) Then, run a second model (B), which includes both off-site and on-site areas and no
treatment practices (do not include swales/drainage control). Model run (B) will have an
outfall “other control practice” applied to it and the modeler needs to adjust the “other
control practice” ‘pollutant concentration reduction’ so that the TSS load generated from
model run (B) is equal to that in model run (A) and the ‘water volume (flow) reduction’
is not reduced.
c) Finally, a third model run (C) is the same as the second model run (B) except that post-
construction treatment practices are now included. Model run (C) will generate the
appropriate TSS load discharged from the post-construction site which accounts for the
additional runoff from off-site area but does not include the off-site pollutant load.
d) Because WinSLAMM includes the pollutant load reduction from the “other control
practice” in the overall percent particulates solid reduction and credit cannot be taken for
control of off-site pollutant load, the percent reduction needs to be adjusted. The
calculation should be made as follows:
100 X (A)Run Model from System Drainage Before Yield Solids eParticulat
(C)Run Model from ControlsAfter Yield Solids eParticulat -1 Reduction Solids eParticulat % Adjusted
12. The NURP particle distribution file is to be used for post-construction modeling. Other
WinSLAMM and P8 parameter input files including rainfall and winter season dates are
identified and available via: http://dnr.wi.gov/topic/stormwater/standards/slamm.html
13. As discussed in items 5, 6, and 7 above, ponds with an outlet on the bottom are prone to scour
and resuspension and may not be eligible or allowed substantially less pollutant removal
credit based on settling. However, credit may be taken for treatment due to infiltration or
8
filtration. (See the Flow Chart attached at the end of this document).
14. An aggressive and efficient street cleaning program might achieve a TSS removal efficiency
of around 10 to 20%. Since the new development TSS performance standard is 80% control,
street cleaning is not a viable option to provide TSS control for new development. Generally,
credit for street cleaning should not be used to meet the redevelopment or highway
reconstruction post-construction standard of 40% TSS control either. A developer will
generally not have authority to ensure that street cleaning will be maintained, and it is not
expected to provide enough TSS control to meet the 40% TSS performance standard for
redevelopment or highway reconstruction.
15. Runoff that infiltrates is assumed to have 100% TSS and TP removal efficiency provided the
facility is designed to prevent scour and resuspension of sediment. Vegetated Swale Standard
1005 has design criteria intended to prevent scour and resuspension, which includes a peak
flow velocity not to exceed 1.5 fps and maximum flow depth of 12 inches for the 2-yr, 24 hr
rainfall event.
16. The settling velocity of particles in runoff is affected by water density, which in turn is
temperature dependent. The DNR recommends that a runoff temperature of no greater than
68 degrees Fahrenheit (20 degrees Celsius) be used to model pollutant removal efficiency.
Peak Flow
17. The post-construction peak flow requirement in ss. NR 151.123 and 151.243, Wis. Adm.
Code, allows the peak flow standard to be met for the post-construction site as a whole.
However, it is recommended that the peak flows not be increased at each outfall that leaves
the site to help limit the potential for off-site erosion.
18. The peak flow requirement does not apply to runoff from off-site which may enter the post-
construction site. As identified in item 11 above, the off-site runoff needs to be accounted for
in determining the treatment performance of treatment devices. On-site drainage systems
need to be properly designed to handle runoff from both on- and off-site areas.
19. Under s. NR 151.123 Wis. Adm. Code, the peak flow requirement does not have to be met if
the post-construction site drains directly into a lake over 5,000 acres or a stream or river
segment draining more than 500 square miles. These water bodies are identified in an
attached map.
20. Use of composite CNs for peak flow calculations (i.e. 1-yr/24-hr rainfall events) is acceptable
for pervious surfaces and disconnected impervious surfaces. Combining directly connected
impervious surfaces with pervious surfaces may result in underestimation of peak flows,
particularly during the 1- and 2-year rainfall events. On sites with storm sewers or directly
connected imperviousness, the designer should either evaluate the connected impervious
areas separately from the pervious areas or provide documentation that the runoff from the
connected impervious area does not control the peak flows during the 1- and 2-year rainfall
events.
See additional discussion about composite CNs under item 26 relative to the infiltration
standard.
Note: HydroCad is a model that is commonly used for calculating peak flows. Hydrocad v 7.1
and earlier versions, calculate a single composite curve number for each subcatchment.
9
Starting with HydroCad v 8.0, the model allows the option of calculating runoff from
pervious and impervious areas separately within a subcatchment but it still averages CNs for
pervious areas in a subcatchment. HydroCad v 10.0 allows the option of calculating flow
independently from each area with a different CN (without averaging CNs) and then
combines the flows to produce the total runoff. Access these options in the HydroCAD
‘Advanced’ tab of the ‘Setting/Calculation’ screen.
21. For determining compliance with the peak flow requirement under s. NR 151.123 or 151.243,
Wis. Adm. Code, DNR recommends use of the National Oceanic and Atmospheric
Administration (NOAA) Atlas 14 Precipitation Frequency Estimates for rainfall depth. The
Natural Resources Conservation Service (NRCS) –Wisconsin has calculated county-specific
Atlas 14 precipitation depths and they are to be used in combination with the appropriate
NRCS Midwest/Southeast (MSE) 3 or 4 precipitation distribution. The NRCS calculated
county-specific Atlas 14 precipitation depths and MSE3 and MSE4 precipitation distributions
are available at:
http://www.nrcs.usda.gov/wps/portal/nrcs/detail/wi/technical/engineering/?cid=nrcs142p2_02
5417
Where the local flood control authority requires use of NRCS Technical Paper 40 (TP-40) or
Bulletin 71 rainfall along with the corresponding type II rainfall distribution, they may be
used. In the Southeastern Wisconsin Region, a SEWRPC (Southeastern Wisconsin Regional
Planning Commission) storm time distribution may be applied with Atlas 14 precipitation
depths. For SEWRPC information on this issue, see:
http://www.sewrpc.org/SEWRPC/Environment/RainfallFrequency.htm
Gravel and Dirt Road CNs
22. Technical Release 55 (TR-55) authored by the United States Department of Agriculture
(USDA) Soil Conservation Service (now Natural Resources Conservation Service or NRCS),
presents simplified procedures to calculate urban hydrology (volume, peak flow, etc.) for
small watersheds. TR-55 lists Curve numbers (CNs), which are used to characterize runoff
properties for a particular soil and ground cover. TR-55 includes CNs for gravel roads and
dirt roads that include right-of-way. HydroCAD documentation suggests that the CN is based
on 30% road surface with a CN of 96 and 70% open space in poor condition. So, 96 would be
a reasonable CN value for gravel and dirt roads where there is not open space. Similarly, the
CN for a gravel parking area should use the same CN as a gravel road (with no open space).
Generally, gravel roads and parking areas should be considered an impervious surface as they
generate substantially more runoff than the existing soil and ground cover condition.
Ballasted Railroad Tracks
23. Ballasted railroad tracks are designed to allow rainfall to efficiently drain laterally from its
tracks and the underlying native soils are compacted, which generally allows for little to no
infiltration. However, ballast rock does have a level of water retention. A Colorado
Department of Transportation Report (No. CDOT-2012-8 Final Report) concluded that in
general 0.3 to 0.4 inches of rainfall is detained in ballasted railroad tracks and with a 0.5-inch
rainfall it produces only a small fraction of runoff. This correlates with a CN of about 84,
which DNR feels is a reasonable CN for the area of the railroad ballasted tracks. With respect
to TSS control, ballasted railroad tracks should be modeled as an unpaved parking source
area.
10
Infiltration
24. The ch. NR 151, Wis. Adm. Code, infiltration standard is based on the pre-development
infiltration volume that occurs on a post-construction site. For compliance with the ch. NR
151, Wis. Adm. Code, infiltration standard, the “stay on” volume may be used to show
compliance with the required infiltration volume. “Stay-on” includes infiltration,
evapotranspiration, and runoff reuse for other uses. Runoff that does not leave the site via
surface discharge is considered “stay-on”.
25. Water from off-site or outside of the proposed development area should not be included in the
analysis to show compliance with the infiltration standard. Whereas, a pollutant treatment
analysis includes all hydrology entering a treatment device as identified in item 11.
26. The use of composite CNs for determining compliance with ch. NR 151, Wis. Adm. Code,
infiltration standard is not appropriate and may not be appropriate for peak flow calculation
as well. Composite CNs for different land cover condition may result in significantly
different runoff volume for small rainfall events (i.e. smaller than 1-yr/24-hr rainfall events)
including an annual average rainfall series.
See additional discussion about composite CNs under item 20 relative to the peak flow
standard.
27. RECARGA is a bioretention/rain garden sizing program developed by the UW-Madison Civil
and Environmental Engineering Water Resources Group. It is publicly available and can be
downloaded via the DNR Runoff Management Models web page:
http://dnr.wi.gov/topic/stormwater/standards/recarga.html
RECARGA may also be used to determine TSS removal credit for non-vegetated infiltration
practices. To eliminate evapotranspiration, the root layer depth can be set at a very small
value (such as 0.1”) but it cannot be set at zero. TSS and TP removal credit of 100% is given
for the recharge (infiltrated) volume.
28. Average annual runoff and infiltration volumes may be calculated using WinSLAMM or
RECARGA. The following approaches could be used:
a) In WinSLAMM, the pre-development runoff volume is calculated by entering the pre-
developed acreage and curve number in the "Pre-Development Runoff Volume" located
under the “Tools” tab. The results are produced in the model output summary under the
“Outfall” and "Runoff Volume" tabs. This can be accomplished in a single model run.
b) In RECARGA, the pre-development infiltration volume can be calculated by inputting
the existing condition tributary area, percent impervious and pervious CN, with a very
small facility area such as 0.01 sf. .
29. Infiltration and bioretention facilities should have their surface outlet raised off the bottom to
ensure infiltration occurs across the entire bottom of the facility. An elevated outlet also helps
keep accumulated sediment within the facility. DNR generally recommends placing the outlet
6 to 12 inches above the top of the engineered soil and designing the facility so the surface of
the facility drains down within 24 hours.
Note: In WinSLAMM, to determine if the 24 hour surface drain down time is being met, in
the Event Performance Summary Detailed Output, subtract the Rain Duration from the
Surface Ponding Duration.
11
30.DNR’s engineered soil filtering layer defined in DNR Bioretention for Infiltration Standard
1004, part V.B.6.d. qualifies as a “filtering layer” as defined in s. NR 151.002(14r), Wis.
Adm. Code. DNR’s engineered soil mixture calls for 15 to 30% compost and 70 to 85% sand.
The sand gradation required in the engineered soil mixture has a very low percent fines level,
however, when mixed with compost, it is considered an acceptable filtering layer. If an
infiltration facility is in an area with a level of percent fines that does not meet the filtering
layer standard, then 2 to 3 inches of compost may be tilled into the top 6 to 12 inches of
native sand for it to qualify as an acceptable filtering layer.
31.The side infiltration rate of a bioretention facility should be set at zero or substantially
reduced because the soils along the side of a bioretention facility are commonly less
conducive to infiltration and may also be compromised by smearing or compaction.
32.An effective infiltration area should not be given double credit both as an infiltration device
and as a pervious area CN. The effective infiltration area should be given a CN of 100 when
modeled as an infiltration facility.
Engineered Soil
33.DNR allows 100% TSS and TP removal credit for the volume of runoff that is infiltrated into
the underlying soil; 80% TSS and 0% TP removal credit for the volume of runoff that is
filtered through an engineered soil filtering layer that meets the requirements of Technical
Standard 1004 (Bioretention for Infiltration), and that is discharged via an underdrain; and
0% removal credit for the volume of runoff that overflows or bypasses the filter. Biofiltration
practices using engineered soil will continue to get TSS filtering credit based on the DNR
allowable level that was in place at the time the DNR received a ch. NR 216, Wis. Adm.
Code, Notice of Intent (NOI) for the construction project or when the practice was installed
where no NOI was required (projects/installations prior to Dec. 20, 2011).
Note: In WinSLAMM, for “engineered soil type” input “manually entered;” then 80% can be
manually entered for the “percent solids reduction due to engineered soil”.
34.The DNR allows an engineered soil infiltration rate of up to 3.6 inches per hour and an
engineered soil porosity of 0.27. The DNR recommends a rock or sand storage area porosity of 0.33.
35.The current engineered soil mixture specified in Technical Standard 1004 with 15 to 30%
compost has not shown a reduction in TP that is filtered. DNR allows 100% TP removal
credit for the volume of runoff that is infiltrated into the underlying soil and 0% removal
credit for the remaining runoff volume. USGS and DNR are working to try to develop an
engineered soil mixture that will reduce TP in filtered runoff. For instance, there are
phosphorus sorbing materials such as iron filings that might be added to enhance phosphorus
removal.
Sand Filter
36.The DNR will allow a filtering credit of 80% for TSS and 35% for TP for treatment through
engineered soil consisting of 100% sand meeting one of the gradation options specified in
Technical Standard 1004 and following the other design requirements contained in Technical
Standard 1004. DNR is trying to develop an engineered soil mixture that would achieve a
greater phosphorus removal benefit than a pure sand filter.
12
Note: Although addition of compost in a filter does not help in removing phosphorus, it may
still be beneficial as a soil amendment for certain plants and also increase the removal of
metals and hydrocarbons from runoff that is filtered.
Permeable Pavement
37. Permeable pavement that is designed, installed and maintained in accordance with DNR
Permeable Pavement Technical Standard 1008 is given filtering credit of 65% for TSS and
35% for TP. A 100% reduction credit is given for TSS and TP in the volume of runoff that is
infiltrated. The design infiltration rate of the soil under the rock storage area should be based
on DNR’s Site Evaluation for Stormwater Infiltration – Standard 1002, Table 2, which gives
design infiltration rates based on soil texture.
In WinSLAMM, version 10 and subsequent versions should be used to model permeable
pavement. In WinSLAMM 9.4 and earlier versions, the porous pavement calculation has an
error in the calculation.
Green Roof
38. Green roofs are generally classified as “extensive” with 2 to 6 inches of soil media or
“intensive” with 6 to 24 inches or more soil media. The soil media and accompanying
vegetation may have a significant effect on runoff volume and peak flow control. However,
roof runoff generally contains a relatively low level of TSS and a green roof may lead to an
increased discharge of nutrients. Therefore, no TSS or TP reduction credit should be taken for
runoff filtered through a green roof.
Connected Imperviousness
39. “Connected Imperviousness” is defined under s. NR 151.002 (6), Wis. Adm. Code. The
percent of connected imperviousness should be no greater than that in the appropriate
WinSLAMM standard land use files unless the percent disconnection is known at the time of
plan development. In P8, the help menu provides standard land use values that can be used as
the percent directly connected versus indirectly connected impervious surfaces.
40. The actual percent connected imperviousness should be used for any site where the
impervious surface drainage patterns are known at the time of stormwater plan development.
This is generally the case for most commercial building sites, schools, condos, parking lot
expansions, etc. Residential subdivisions and business parks are two development types
where detailed building, parking and/or driveway drainage may not be known at the time of
plan development.
41. When evaluating the flow length for impervious surface disconnection, flow lengths should
not extend into vegetated swales, filter strips, areas of concentrated flow, or other storm water
treatment devices,
42. Disconnection of rooftops from one- and two-family residential dwellings may be assumed
provided the runoff has a flow length of at least 20 feet over a pervious area in good
condition.
13
43. Disconnection of impervious surfaces other than rooftops from one- and two-family
residential dwellings may be assumed provided all of the following are met:
a) The source area flow length does not exceed 75 feet,
b) The pervious area is covered with a self-sustaining vegetation in “good” condition and at
a slope not exceeding 8%,
c) The pervious area flow length is at least as long as the contributing impervious area flow
length and there can be no additional runoff flowing into the pervious area other than that
from the source area.
d) The pervious area must receive runoff in a sheet flow manner across an impervious area
with a pervious width at least as wide as the contributing impervious source area.
Filter Strips
44. Filter strip treatment may be modeled in WinSLAMM, but only for treating sheet flow runoff
traveling less than 100 feet in the direction of flow. Generally, sheet flow conditions are not
maintained for more than 100 feet, and concentrated flow commonly occurs within less than
100 feet depending on the topography.
Hydrodynamic Proprietary Devices
45. Manufacturers of hydrodynamic proprietary devices commonly estimate TSS reduction
efficiencies for their products. However, the modeled efficiency supplied by the manufacturer
may only be used if the modeling and lab analysis conforms to Technical Standard 1006
“Proprietary Storm Water Sedimentation Devices”. Otherwise, such devices should be
modeled in WinSLAMM utilizing the Hydrodynamic Device source area control practice. As
of the date this guidance was released, no proprietary hydrodynamic settling devices have
been reviewed by the DNR as described in Standard 1006, nor have any such devices been
included in WinSLAMM.
Transportation Facility – Swale Treatment Performance Standard
46. Pursuant to s. NR 151.249 (1), Wis. Adm. Code, in some cases transportation facilities that
use swales for runoff conveyance and pollutant removal are exempt from TSS, peak
discharge, and infiltration performance standards. However, the exemption does not specify
or assume an amount of treatment credit. If the amount of treatment credit is needed, design,
model, construct, and maintain swales in accordance with DNR guidance, the Vegetated
Swale Technical Standard 1005, and the Site Evaluation for Infiltration Technical Standard
1002.
47. Some water quality models require a swale bottom width to be entered and which is not zero.
If a “V” swale is proposed then a 0.1’ bottom width should be entered.
Notes:
1. This chart does not address pretreatment of runoff prior to infiltration. Pretreatment is required before infiltrating runoff from parking lots and new road construction
in commercial, industrial and institutional areas under s. NR 151.124(7), Wis. Adm. Code.
2. Technical standard 1004 requires a two foot depth of engineered soil.
3 As identified in item 5 of the Post-Construction Modeling Guidance memo, WinSLAMM 10.3.2 will give some credit for a pond with an outlet on the bottom.
Updated: December 2018
DETERMINING WATER QUALITY CREDIT FOR STORM WATER DETENTION POND
FOR COMPLIANCE WITH CONSTRUCTION AND MUNICIPAL PERFORMANCE STANDARDS
STORM WATER
BASIN DESIGN
Design per wet detention
basin technical standard 1001
then 80% TSS removal credit
given or establish efficiency
by modeling as a wet basin
Is the depth of the permanent
pool greater than or equal to 3
feet?
Does design of the storm
water basin include a
permanent pool?
Is there a sand or
engineered soil
filtration layer2
NO
NO
YES NO No water quality
credit for TSS
settlement,
except see note
3.
Is there an underdrain
system?
YES
Design per Tech Standard
1004 and establish efficiency
by modeling as a biofilter or
by another method approved
by the department
Depreciate treatment
efficiency based on
permanent pool depth (i.e.
1.5-ft. depth = half the settling
efficiency given.3 The liner
requirements of Technical
Standard 1001 apply
Does the design include
infiltration or filtration?
Design per Technical Standard 1003 and establish
efficiency by modeling as an infiltration basin or by
using the DNR Technical Note for Sizing Infiltration
Basins and Bioretention Devices To Meet State of
Wisconsin Stormwater Infiltration Performance
Standards1
YES
YES
Model as a biofilter with no
filtration1
NO
YES NO
BadRiver
Chippewa RiverS. Fk. FlambeauRiver
Jum p R iverFlambeauRiverRed Cedar RiverChippewaRiverEauClaireRiver
NamekagonRiver
St. CroixRiverTrempeleauRiver BlackRiverWisconsinRiverTomahawkRiver
YellowRiver
LemonweirRiver
BarabooRiver
Wisconsin RiverKickapoo RiverAppleRiver
Pine River
Peshtigo River
Oconto RiverMenomi
n
e
e
Ri
v
e
r
FoxRiverWolfRiverEmbarassRiver
ManitowocRiver
MilwaukeeRiver
RockRiverCrawfishRiver
Sugar R.
Mississippi
RiverPecatonicaRiver FoxRiver
LakeMendota
BeaverDamLake
LakeGeneva
LakeWisconsin
PuckawayLake
GreenLake
LakePoyganLake Buttedes Morts
LakeWinnebago
ChippewaLake
Lac CourteOreilles
Turtle FlambeauFlowage
Castle Rock Lake
PetenwellLake
LakePepin
LakeOnalaska
LakeWissota
0 25 50 Miles
µ
LakeKoshkonong
River Segments Draining more than 500 sq. miles
Lakes greater than 5000 Acres
County Boundaries
Yahara River
SaintLouisRiver
1:2,500,000
Lakes Larger than 5000 Acres and Stream Segments Draining more than 500 Square Miles
WDNR September 2017
WISCONSIN DEPARTMENT OF NATURAL RESOURCES
TECHNICAL STANDARD
SITE EVALUATION FOR STORM WATER INFILTRATION
1002
DEFINITION This standard defines site evaluation procedures to: (1) Perform an initial screening of a development site1 to determine its suitability for infiltration, (2) Evaluate each area within a development site that is selected for infiltration, and (3) Prepare a site evaluation report. PURPOSE (1) Protect groundwater from surface water pollution sources, (2) Identify areas suitable for infiltration,
(3) Establish methods to a) characterize the site, and b) screen for exclusions and exemptions under ch. NR 151, Wis. Adm. Code,
(4) Establish requirements for siting an infiltration device and the selection of design infiltration rates, (5) Define requirements for a site evaluation report documenting that appropriate areas are selected
for infiltration and that an appropriate design infiltration rate is used, and CONDITIONS WHERE PRACTICE APPLIES
This standard is intended for development sites being considered for storm water infiltration devices. Additional site location requirements may be imposed by other storm water infiltration device technical standards. Be aware of applicable federal, state and local laws, rules, regulations or permit requirements governing infiltration devices. This standard does not contain the text of federal, state or local laws. Note that infiltration devices are commonly regulated as plumbing when in connection with a piping system, see ch. SPS 382, Wis. Adm. Code. This technical standard enables state and local authorities to implement infiltration requirements with uniformity. CRITERIA The site evaluation consists of four steps (Steps A – D) for locating the optimal areas for infiltration and establishing the design infiltration rate for properly sizing infiltration devices (below, and Figure 1).
To avoid costly redesigns, it is recommended to complete Step A before the preliminary plat, and Step B before the final plat or Certified Survey Map (CSM) is approved. For regional infiltration devices, and for
devices constructed on public right-of-ways, public land, or jointly owned land, Step C should be completed before the final plat or final CSM approval. Infiltration devices distributed around a development will usually better sustain the existing hydrology, and can improve the lifespan of devices, compared to a single regional device. Information collected in Step A may be used to explore the potential for multiple infiltration areas versus a regional device.
1 Words in the standard that are shown in italics are described in the Definitions section. The words are italicized the first time they are used in the text.
Technical Standards are reviewed periodically and updated if needed. To obtain the current version of this standard, contact your local WDNR office or the Standards Oversight Council office in Madison, WI at (608) 441-2677.
WDNR September 2017
1002-TS-2
Step A. Initial Site Screening Step B. Preliminary Field Verification of the Initial Site Screening
Step C. Establishment of Design Infiltration Rate
Step C.1. Field Evaluation of Specific Infiltration Areas
Step C.2. Infiltration Rate Exemption
Step C.3. Infiltration Rate Determination
Infiltration Option 1 – Infiltration Rate Not Measured, Soil Compaction Mitigated
Infiltration Option 2 – Infiltration Rate Measured with In-Field Device, Soil Compaction Mitigated
Infiltration Option 3 – Infiltration Rate Not Measured, Soil Compaction Not Mitigated
Step D. Soil and Site Evaluation Report
Figures and Attachments: Figure 1. Site Evaluation for Infiltration Flow Chart
Figure 2. Example Bioretention Basin Section
Figure 3. Example Bioretention Basin Section with Underdrain Section
Figure 4. Example Infiltration Basin Section
Attachment 1. Hydrologic Condition Form
Attachment 2. Soil and Site Evaluation Form
Record information for Steps B and C as noted in Step D. Prepare a single report for the infiltration
evaluation. Step A. Initial Site Screening The purpose of Step A is to use existing available information to determine if installation is limited by s.
NR 151.124 (3)(a) or (4), Wis. Adm. Code, and where field work is needed for Step B. A wetland determination or delineation may be needed to identify boundaries of wetlands within or near the site, but is not required as part of the soil evaluation. The initial screening may be conducted without fieldwork to determine the following:
(See a list of references and resources in the Considerations section).
(1) Site topography and slopes greater than 20%, (2) Site soil infiltration capacity characteristics as defined in NRCS County soil surveys or other relevant source,
(3) Soil parent material obtained from published soil descriptions, (4) Hydrologic condition based on the condition values for the current and two previous months’ rainfall (Attachment 1), (5) Soil map unit, depth to groundwater and depth to restrictive features; use seasonally high groundwater information where available, (6) Distance to sites listed on the Wisconsin Remediation and Redevelopment Database (WRRD) sites within 500 feet from the perimeter of the development site,
WDNR September 2017
1002-TS-3
(7) Known presence of endangered species habitat, (8) Location of rivers, streams, lakes, and floodplains, (9) Location of mapped wetlands, hydric soil and potentially hydric soil based on the Wisconsin Wetland Inventory (WWI), which can be accessed via the WDNR Surface Water Data Viewer,
(10) Areas prohibited from installation of storm water infiltration devices by s. NR 151.124(3)(a) and (4)(a), Wis. Adm. Code, including, but not limited to, setbacks from direct conduits to
groundwater such as wells, sinkholes, and karst features due to the potential for groundwater contamination,
(11) Areas exempt from the requirement to install storm water infiltration devices by ss. NR 151.124 (3)(b) and (4)(c) Wis. Adm. Code,
(12) Potential impact to utilities, and (13) Potential impact to adjacent property.
Step B. Preliminary Field Verification of the Initial Site Screening
The purpose of Step B is to field-verify information from Step A for all potential areas of the development site considered suitable for infiltration. Evaluate the areas for depth to groundwater, depth to bedrock, and soil texture to verify any exemption and exclusion found in Step A. Soil borings are acceptable for Step B. Sandy loams, loams, silt loams, silts and all clay textural classifications are assumed to meet the percent
fines limitations of a filtering layer in s. NR 151.002(14r), Wis. Adm. Code, for both 3 and 5 foot soil layers. Coarse sand does not meet s. NR 151.002(14r), Wis. Adm. Code, limitations for a 3 foot soil layer consisting of 20% fines. Other sand textures and loamy sands may require the percent fines level be verified with a sieve analysis. Step C. Establishment of Design Infiltration Rate The purpose of Step C is to determine if locations identified for infiltration devices are suitable for infiltration and to provide the required information to design the device.
Test pits are required for Step C. If a backhoe is unable to excavate a test pit to the required depth, then
soil borings may be used to evaluate the depth below that which the backhoe is able to reach. It is expected that a medium-sized backhoe can reach at least 15 feet below grade. Information from soil
borings and monitoring well logs may supplement data from test pits. Refer to Attachment 2 for a soil and site evaluation form.
Step C.1. Field Evaluation of Specific Infiltration Areas. Construct the minimum number of test pits for each infiltration device as defined in Table 1. Local
agencies may require additional test pits for soil evaluation. Excavate test pits to a depth of at least 5 feet below the native soil interface elevation (Figures 2 – 4) or to a limiting layer, such as bedrock or groundwater. If no limiting layer is encountered, continue excavation to 5 feet below the native soil interface even if perched conditions are encountered. For example, if the native soil interface of an infiltration device is 8 feet below the existing grade, a test pit at least 13 feet deep will be needed (8 feet plus 5 feet). Follow OSHA safety protocol for designing and entering test pits. To avoid entering test pits, soil may also be examined from the surface as it is excavated. Complete morphological soil profile description using the NRCS Field Book for Describing and Sampling
Soils, (latest edition). Soil profile descriptions are to be made by a professional meeting the Qualifications (see Step D). Document the test pits using the Soil Test Pit Evaluation form in Attachment 1.
WDNR September 2017
1002-TS-4
Table 1. Evaluation Requirements to Proposed Infiltration Devices Note 1
Infiltration Device (Technical Standard Note 2, Note 3)
Tests Required Minimum Number of Test Pits Required Note 4, Note 5
Rain Garden Soil texture evaluation or infiltration test
N/A
Infiltration Trenches (1007)
Test pits 1 test pit/100 linear feet of trench with a minimum of 2 test pits, and sufficient to determine / confirm variability
Vegetated Swale (1005)
Test pits
1 test pit/ 500 linear feet of swale with
a minimum of 2 test pits, and sufficient to determine / confirm variability
Bioretention Systems (1004)
Test pits
1 test pit or a number sufficient to
assess infiltration potential, and sufficient to determine / confirm
variability
Surface Infiltration Basins (1003)
Test pits
2 test pits then an additional test pit /10,000 square feet and sufficient to determine / confirm variability
Subsurface Dispersal Systems
(N/A) greater than 15 feet in width
Test pits
2 test pits then an additional test pit /10,000 square feet and sufficient to determine / confirm
variability
Permeable Pavement Systems (1008)
Test pits
2 test pits then an additional test pit /10,000 square feet and sufficient to determine / confirm variability
Note 1 Maintain trench safety requirements; test pit evaluations can be made from the surface without entering the pit. Note 2 Technical standards refer to the corresponding WDNR design technical standard containing design criteria for this practice. Note 3 Where initial site borings show uniform soils throughout the site, the professional meeting the Qualifications (see
Step D) may reduce the number of test pits, provided information from both test pits and soil borings confirm a uniform soil condition across the proposed device location. Note 4 Test pits are optimally located within 10 feet of the footprint perimeter, and not within the footprint. Note 5 If a backhoe is unable to excavate a test pit deep enough from the existing surface to reach 5 feet below the native soil interface, then soil borings may be used to evaluate the depth below the which the backhoe is unable to reach. It is expected that even a medium sized backhoe can reach at least 15 feet below grade.
Step C.2. Infiltration Rate Exemption. To determine if a site is eligible for exemption from infiltration under s. NR 151.124(4)(c), Wis. Adm. Code, use a scientifically credible field test method unless the least permeable soil horizon within five feet below the native soil interface is one of the following: sandy clay loam, clay loam, silty clay loam, sandy clay, silty clay, or clay. Take at least three infiltration tests at the optimal infiltration location per the criteria obtained in Step B, and distribute tests so that they best represent the area being tested (see Step C.3. Infiltration Option 2 for infiltration test methods). Conduct tests within the native soil layer being evaluated for exemption. For a site to be exempt from infiltration requirements, at least two-thirds of tests are to have a measured infiltration rate of less than 0.6 in/hr. Use the infiltration rate from actual field measurements to request an exemption to infiltration requirements; correction factors do not apply.
WDNR September 2017
1002-TS-5
Step C.3. Infiltration Rate Determination. The purpose of this step is to determine a design infiltration rate (Infiltration Options 1 – 3). Use Infiltration Options below to determine the design infiltration rate. Examples calculate the static infiltration rate.
Note that soil compaction mitigation reduces the soil density and promotes infiltration.
Infiltration Option 1 – Infiltration Rate Not Measured, Soil Compaction Mitigated Using information from soil test pits, select the design static infiltration rate from Table 2 based on soil
texture of the least permeable soil horizon within 5 feet below the native soil interface. See Example 1. Table 2. Design Static Infiltration Rates for Soil Textures Receiving Storm Water Note 1 Soil Texture Design Static Infiltration Rate Without Measurement (Inches/Hour) Note 2 Coarse sand or coarser 3.60
Loamy coarse sand 3.60
Sand 3.60
Loamy sand 1.63
Sandy loam, fine sand, loamy sand, very fine sand, and loamy fine sand 0.50
Loam 0.24
Silt loam 0.13
Sandy clay loam 0.11
Clay loam 0.03 Silty Clay loam 0.04 Note 3 Sandy clay 0.04
Silty clay 0.07
Clay 0.07
Note 1 These infiltration rates are not to be used to request exemption from infiltration requirements. Note 2Infiltration rates represent the lowest value for each textural class presented in Table 2 of Rawls, 1998. Note 3Infiltration rate is an average based on Rawls, 1982 and Clapp & Hornberger, 1978. Table 2 assumes separation from the native soil interface to a limiting layer such that mounding of water will not reach the native soil interface. A regulatory authority may require a mounding analysis when concerned that mounding may impair the function of the device or have an adverse impact to property. See Considerations section for more information. Where adverse soil structure is present, such as moderate to strong platy soil structure, compacted or cemented soil horizons, or massive soil conditions with high bulk density reduce the design static infiltration rates per judgment of an individual meeting the Qualifications in Step D.
WDNR September 2017
1002-TS-6
Example 1. (1) Calculate the design static infiltration rate (Fstatic) where the native soil interface is 4 feet below existing grade (Table E1).
Table E1. Observed Soil Conditions for Example 1 Soil Depth Below Existing Grade (Inches) Soil Texture Infiltration Rate Note 1 (Inches/Hour)
0 – 12 Silt Loam 0.13
12 – 24 Sandy Loam 0.50
24 – 72 Loam 0.24
72 – 130 Silt Loam 0.13
130 – 180 Loam 0.24
Note 1Infiltration rates are from Table 2. Solution 1.
(1) Fstatic = the soil texture with the lowest infiltration rate within 5 feet below the native soil interface (2) Solve for Fstatic: Add 5 feet to the depth of the native soil interface (4 feet) for a total of 9 feet of
depth. The soil texture with the lowest infiltration rate from 4 feet to 9 feet (48 to 108 inches) below existing grade is silt loam, for which Table E1 shows an infiltration rate of 0.13 in/hr. (3) Fstatic = 0.13 in/hr.
Infiltration Option 2 – Infiltration Rate Measured with In-Field Device, Soil Compaction Mitigated Conduct two field infiltration tests within each soil test pit at the native soil interface as required in Table 1
and calculate a geometric mean infiltration rate. Select infiltration measurement location(s) representative of the site being tested. Conduct the infiltration
tests at the native soil interface elevation of the proposed infiltration device. If the infiltration rate is measured with a Double-Ring Infiltrometer, use the requirements of ASTM D3385 for the field test, except
that the test period may be reduced to 2 hours and may be a falling head test (WDNR 2010). Record at least 5 water depth measurements spaced throughout the test period to determine the lowest infiltration
rate that occurs during the test. An infiltration test may be conducted over a period of less than 2 hours only if water is depleted during testing due to a high infiltration rate (e.g., > 10 in/hr). In this case, graph
the infiltration rate change with respect to time using the measured data points to project the infiltration rate out to 2 hours. Infiltration testing is used to determine the lowest infiltration rate under a saturated soil condition during non-frozen soil conditions. Infiltration test results may not be representative due to macro pores (e.g.,
soil cracks, worm holes); therefore, avoid areas with macro pores. If cracks in soil are due to dry soil, do not test until soil has taken on adequate moisture to eliminate the soil cracks.
The geometric mean of infiltration test results should be used. However, it may be appropriate to group certain test results where an infiltration trend is apparent and assign different geometric mean rates accordingly. Grouping of results may be done based on soil type or spatial reasons to provide representative results. Where an infiltration rate is too low to measure, a rate of 0.03 in/hr may be used to calculate a geometric mean of the dataset (the dataset’s values must be greater than zero to calculate a geometric mean). To calculate the static infiltration rate, (1) Determine the ratio of textural infiltration rates (R) by dividing the textural infiltration rate (Table 2) at the native soil interface by the lowest textural infiltration rate (Table 2) within 5 feet below the native soil interface.
WDNR September 2017
1002-TS-7
(2) Use this ratio to select the appropriate correction factor (A) from Table 3. The correction factor is based on compaction mitigation occurring, and adjusts the measured infiltration rates for the
occurrence of less permeable soil horizons below the surface and the potential variability in the subsurface soil horizons throughout the infiltration site.
(3) Next, divide the geometric mean of the measured infiltration rates by the correction factor (A) to obtain the static infiltration rate.
Table 3. Correction Factors for Measured Infiltration Rates at Infiltration Devices Note 1
Ratio of Textural Infiltration Rates (R) Correction Factor (A)
1 2.5
1.1 to 4.0 3.5
4.1 to 8.0 4.5
8.1 to 16.0 6.5
16.1 or greater 8.5
Note 1Washington State Department of Ecology, 2001.
Example 2. (1) Calculate the static design infiltration rate (Fstatic) for an infiltration device having Double-Ring Infiltrometer measurements with a geometric mean (G) infiltration rate of 1.45 in/hr. (2) The infiltration device native soil interface is 4 feet (48 inches) below existing grade. No groundwater or redoximorphic features were encountered.
Table E2. Observed Soil Conditions for Example 2 Soil Depth Below Existing Grade (Inches) Soil Texture Infiltration Rate Note 1 (Inches/Hour)
0 – 12 Silt Loam 0.13
12 – 84 Sandy Loam 0.50
84 – 180 Loam 0.24
Note 1Infiltration rates are from Table 2.
Solution 2.
(1) Calculate R, the ratio of textural infiltration rates = TN / TL Where:
TN = Textural infiltration rate at the native soil interface (Table 2, sandy loam) TL = Lowest textural infiltration rate within 5 feet below the native soil interface (Table 2, loam) (2) R = 0.50 in/hr (sandy loam) / 0.24 in/hr (loam) = 2.08 (3) From Table 3, the correction factor (A) for 2.08 is 3.5. (4) Calculate Fstatic, the static infiltration rate = G / A Where: G = the geometric mean of the measured infiltration rate = 1.45 in/hr A = the correction factor from Table 3 based on R.
(5) Fstatic = 1.45 in/hr / 3.5 = 0.41 in/hr
WDNR September 2017
1002-TS-8
Infiltration Option 3 – Infiltration Rate Not Measured, Soil Compaction Not Mitigated Notice: This section is not applicable where soil compaction mitigation actions will be implemented at an infiltration device (see Definitions). Mitigating soil compaction is important, as both topsoil and subsoils can become compacted during
construction. It is best to avoid compacting areas, primarily during construction, in the first place, especially areas where infiltration devices will be located. However, construction of an infiltration device
can lead to soil compaction, so appropriate actions should be taken to mitigate potential compaction. Soil compaction mitigation actions will vary based on the site and type of infiltration device. Individual
infiltration design standards include actions to avoid and mitigate soil compaction. Where actions are not taken to mitigate soil compaction, apply the correction factor (B) from Table 4 in this section to further
reduce the design infiltration rate of the infiltration device.
Table 4. Static Infiltration Rate Correction Factor for Incidental Soil Compaction Note 1 Compacted Soil Type Correction Factor (B) Sand
Coarse Sand or Coarser 0.9 Loamy Coarse Sand
Sand
Loamy Sand
Loam
Sandy Loam 0.4 Loam Silt Loam Sandy Clay Loam
Clay
Clay Loam
0.2
Silty Clay Loam
Sandy Clay
Silty Clay
Clay
Example 3. (1) Calculate the static infiltration rate (Fstatic) where soil compaction mitigation is not performed.
Observations from the test pit indicate that the soil texture with the lowest permeability within 5 feet below the native soil interface is sandy loam.
Solution 3: (1) Fstatic = TL * B Where: TL = Lowest textural infiltration rate (Table 2) within 5 feet below the native soil interface B = the correction factor from Table 4 (2) Fstatic = 0.5 in/hr (Table 2 for sandy loam) * 0.4 (Table 4 correction factor for sandy loam) Fstatic = 0.2 in/hr
Note that if a vegetated swale is proposed, a dynamic infiltration rate is used. Fdynamic = Fstatic * 0.5
WDNR September 2017
1002-TS-9
Step D – Soil and Site Evaluation Report Include the site information required in Steps B and C in the Soil and Site Evaluation Report. Complete
the single report prior to the construction plan submittal for regulatory approval. Include the following in the report:
(1) The date the information was collected. (2) A legible site plan/map that is presented on paper that is no less than 8 ½ X 11 inches in size
and: (a) Is drawn to scale, (b) Includes a site location map, (c) Include a north arrow, (d) Includes a permanent vertical and horizontal reference point, (e) Illustrates the entire development site, (f) Shows all areas of planned filling and/or cutting if known, (g) Shows the percent and direction of land slope for the site or contour lines, (h) Highlights areas with slopes over 20%, (i) Shows all floodplain information (elevations and locations) that is pertinent to the site, (j) Shows the locations of the soil borings and test pits, (k) Shows the location by site grid and elevations of existing surface and bottom of all test pits/borings included in the report, (l) Shows location of wetlands within the entire development site as field delineated and surveyed, (m) Shows location of private wells within 100 feet of the development site, and public wells within 400 feet of the development site, and (n) Shows location of karst features within 1,000 feet downgradient and 100 feet upgradient of the development site. Write soil profile descriptions in accordance with the descriptive procedures, terminology and interpretations found in the Field Book for Describing and Sampling Soils, USDA, NRCS (latest edition).
Thaw frozen soil material prior to conducting evaluations for soil color, texture, structure and consistency. In addition to the data determined in Steps B and C, include the following information for each soil horizon or layer of the soil profiles: (1) Thickness, in inches or decimal feet, (2) Munsell soil color notation, (3) Soil mottle or redoximorphic feature color, abundance, size and contrast, (4) USDA soil textural class with rock fragment modifiers, (5) Soil structure, grade size and shape, (6) Soil consistence, root abundance and size, (7) Soil horizon boundary, distinctness and topography, (8) Occurrence of saturated soil, groundwater, bedrock or disturbed soil, (9) Bedrock type, weather-fractured or unfractured, and elevation,
(10)Proposed native soil interface elevation, and
(11)Seasonal and current groundwater elevations.
WDNR September 2017
1002-TS-10
QUALIFICATIONS Site Evaluation Complete Steps A and B by a Licensed Professional with experience in soil investigations, interpretation,
and classification acceptable to the authority having jurisdiction. Soil Evaluation Complete Step C by a Licensed Professional Soil Scientist, or Licensed Professional Geologist as licensed by the Wisconsin Department of Safety and Professional Services (DSPS) with experience in soil investigations, interpretation, and classification or other licensed professional with 5 years of experience acceptable to the authority having jurisdiction until December 31, 2022. After January 1, 2023 complete Step C by a Licensed Professional Soil Scientist or Licensed Professional Geologist as licensed by the DSPS.
CONSIDERATIONS
Additional recommendations relating to design that may enhance the use of, or avoid problems with this practice but are not required to insure its function are as follows:
(1) As part of the permitting process, the development site should be checked to determine the potential for cultural resources. If cultural resources are known or suspected to be on site, include their location on relevant permit applications. (2) If a site is suspected of having contaminated soil or other materials from its prior land use, historic fill or other reason, then an evaluation to characterize the potential contamination may be warranted (an Environmental Site Assessment may be justified). New fill should be evaluated for contamination before it is brought to a new site. DNR guidance publications WA-1820 “Waste Soil
Determinations and Identifying Clean Soil” (http://dnr.wi.gov/news/input/Guidance.html) and RR- 060 “Management of Contaminated Soils and Other Solid Wastes”
(http://dnr.wi.gov/files/PDF/pubs/rr/RR060.pdf) were developed to assist generators, regulators and property owners to manage waste properly. (3) The permitting process requirements for development sites vary across the state and may also vary within a municipality depending on the number of lots being developed. The timing of Steps A, B, and C may need to be adjusted for the type of approval process. (4) Be aware that any activity that will result in a discharge of fill material to a wetland will require a permit under s. 381.36 Wis. Stats. Wetlands are defined in s 23.32 Wis. States and Ch. NR 103, Wis. Adm. Code. (5) Resources available for completing Steps A and C: (a) USDA-NRCS Web Soil Survey, websoilsurvey.sc.egov.usda.gov/ (b) Sites listed in the Wisconsin Remediation and Redevelopment Database (WRRD), including GIS tool, http://dnr.wi.gov/topic/Brownfields/WRRD.html (c) Floodplain areas as regulated under s. 87.30, Wis. Stats. and chs. NR 30, 31, and 116, Wis. Adm. Code. (d) NRCS Climate Analysis for Wetlands Tables (WETS Tables, see Attachment 1), https://www.wcc.nrcs.usda.gov/climate/navigate_wets.html (e) Endangered species habitat as shown on National Heritage Inventory County maps, http://dnr.wi.gov/topic/nhi. (f) Access points and road setbacks as determined by county or municipal zoning plans.
WDNR September 2017
1002-TS-11
(g) Existing reports concerning the groundwater and bedrock. Examples include: Publications from USGS, NRCS, Regional Planning Commissions, WDNR, DATCP,
WisDOT, UW system or WGNHS. (h) The Drinking Water and Groundwater pages of the WDNR http://dnr.wi.gov/topic/DrinkingWater/ (i) The Wisconsin Grain Size Database http://wgnhs.uwex.edu/maps/data (j) WDNR Surface Water Data Viewer http://dnr.wi.gov/topic/surfacewater/swdv/ (k) Occupational Safety and Health Administration www.osha.gov
(l) WDNR’s Process to Assess and Model Grass Swales guidance. Steps for “modified” Double Ring infiltrometer test are given within this guidance. http://dnr.wi.gov/topic/stormwater/standards/ms4_modeling.html (6) If a karst feature is located within the site, a Karst Inventory Form from the Wisconsin Geological and Natural History Survey should be filled out (https://wgnhs.uwex.edu/water-environment/karst- sinkholes/). (7) Groundwater monitoring wells, constructed as per ch. NR 141, Wis. Adm. Code, can be used to
determine the groundwater level. GeoProbes may be used for groundwater levels, provided that groundwater levels have reached a steady state condition. Large sites considered for infiltration basins may need to be evaluated for the direction of groundwater flow.
(8) Consider conducting a groundwater mounding analysis to verify that the highest anticipated
groundwater level does not approach the native soil interface. The infiltration rate into saturated soil in this case may be at or near zero. This standard requires that limiting layers within 5 feet
below the native soil interface of an infiltration device be considered in the design infiltration rate. It is also possible for a limiting layer more than 5 feet below the native soil interface to affect an infiltration device where lateral movement is limited. Increased mounding height, and therefore the potential for increased infiltration device drawdown time, are more likely to occur under the
following conditions: shallow depth to groundwater or limiting layer, increased infiltration device size, decreased device length/width ratio, the presence of low-hydraulic conductivity material, thin
aquifer thickness, and shallow water table gradient. It is also appropriate to conduct a mounding analysis in locations where mounding may impact basements or adjacent property. Refer to http://dnr.wi.gov/topic/stormwater/standards/gw_mounding.html for mounding calculation guidance.
(9) Ch. NR 151, Wis. Adm. Code provides for a maximum area to be dedicated for infiltration depending upon land use. This cap can be voluntarily exceeded.
(10) One or more areas within a development site may be selected for infiltration. A development site with many areas suitable for infiltration is a good candidate for a dispersed approach to
infiltration. It may be beneficial to contrast regional devices with onsite devices for sites that receive runoff from one lot or a single source area within a lot, such as rooftop or parking lot.
(11) Consider conducting a soil evaluation to a depth of 15 feet below the existing grade as standard protocol, unless bedrock or groundwater is reached, and deeper if this area will be ‘cut,’ or lowered, from existing grade (12) In some situations, adding fill to a location to increase the separation distance between the proposed bottom of an infiltration device and a limiting layer may make a location suitable for infiltration.
(13) The authority having jurisdiction will decide if a proposed alternative infiltration test method is acceptable for new devices and existing swales. Discuss the proposed plan with the authority before detail design. (14) The Modified Philip Dunne infiltration test is suitable for assessment of required maintenance because accumulation of fine particles limit the infiltration rate in these practices.
WDNR September 2017
1002-TS-12
(15) Devices located on or near final slopes of ≥20% may be unstable. Consider a slope stability calculation.
(16) No construction sediment should enter the infiltration device. This includes sediment from site grading as well as construction activities. Avoid stockpiling soils and vehicle travel on the
infiltration area. If possible, delineate and protect from compaction areas selected for infiltration during grading and construction. This will help to preserve the infiltration rate and extend the life
of the device. Where compaction occurs, follow mitigation requirements as outlined in design technical standards.
(17) Class V injection wells are not addressed in this document; see http://dnr.wi.gov/topic/wells/uiw.html for details on these types of wells. (18) In projects which involve piping of storm water, consult plumbing code in ch. SPS 382, Wis. Adm. Code. (19) Storm water infiltration devices may fail prematurely if there is: (a) An inaccurate estimation of the design infiltration rate, (b) An inaccurate estimation of the seasonal high water table or bedrock, (c) Excessive compacting or sediment loading during construction, or (d) No pretreatment for post-development runoff and lack of maintenance. (20) Consider vegetation species and root depth and their potential to enhance the infiltration rate.
REFERENCES Ahmed F., and J.S. Gulliver. (2010). Manual for the Modified Philip-Dunne (MPD) Infiltrometer. St. Anthony Falls Laboratory (http://www.safl.umn.edu).
Ahmed, F., J.S. Gulliver, and J.L. Nieber. (2015). Field infiltration measurements in grassed roadside drainage ditches: Spatial and temporal variability. Journal of Hydrology, 530:604-611.
ASTM D 3385 – 88, 1988. Standard Test Method for Infiltration Rate of Soils in Field Using Double-Ring Infiltrometers.
Ch. NR 30, Wis. Adm. Code
Ch. NR 31, Wis. Adm. Code
Ch. NR 116, Wis. Adm. Code
Ch. NR 103, Wis. Adm. Code
Ch. NR 141, Wis. Adm. Code
Ch. NR 151, Wis. Adm. Code
Ch. NR 811, Wis. Adm. Code (line 71)
Ch. NR 812, Wis. Adm. Code (line 71)
Ch. NR 815, Wis. Adm. Code (line 552)
Ch. SPS 382, Wis. Adm. Code Design, Construction, Installation, Supervision, Maintenance and
Inspection of Plumbing. Clapp, R.W. and G.M., Hornberger. 1978. Empirical equations for some hydraulic properties. Water
Resources Research 14:601-604. Ferguson, B.K., 1994. Storm water Infiltration, CRC Press Inc.
Finnemore, E. J., 1993. Estimation of Ground-Water Mounding Beneath Septic Drain Fields. Groundwater, Vol. 31 No. 6, pp. 884-889.
WDNR September 2017
1002-TS-13
Finnemore, E.J., 1995. A program to calculate Ground-Water Mound Heights. Groundwater, Vol. 33, No. 1.
Hantush, M. S., 1967. Growth and Decay of Groundwater-Mounds in Response to Uniform Percolation. Water Resources Research, Vol. 3, No. 1, pp. 227-234.
Lowndes, M., 2000. “Infiltration Basins and Trenches” The Wisconsin Storm water Manual, G3691-3.
Munsell Color (Firm), 2010. Munsell soil color charts: with genuine Munsell color chips. Grand Rapids,
MI:Munsell Color. Rawls, W.J., D.L. Brakensiek and K.E. Saxton, 1982. Estimation of Soil Water Properties, Transactions of
the American Society of Agricultural Engineers Vol. 25, No. 5 pp. 1316 –1320 and 1328. Rawls, W.J., Gimenez, and Grossman, R., 1998. Use of Soil Texture, Bulk Density and Slope of Water Retention Curve to Predict Saturated Hydraulic Conductivity, ASAE, Vol. 41(2), pp. 983-988. Schoeneberger, P.J., D.A. Wysocki, E.C. Benham, and Soil Survey Staff. 2012. Field book for describing and sampling soils, Version 3.0. Natural Resources Conservation Service, National Soil Survey Center, Lincoln, NE.
Washington State Department of Ecology, 2001. Storm Water Management Manual for Western Washington, Publication Numbers 99-11 through 99-15.
Wisconsin Department of Natural Resources, Memorandum: Process to Assess and Model Grass Swales for ss. NR 151.13(2) and NR 216.07(6), WIs. Adm. Code, November 24, 2010. http://dnr.wi.gov/topic/stormwater/documents/GrassSwales080424.pdf.
DEFINITIONS Aquiclude: A geological material through which zero water flow occurs. Aquitard: Compacted layer of clay, silt or rock that attenuates water flow underground. Bedrock: A consolidated rock, or weathered in place parent material larger than 2 mm in size and greater than 50 percent of the soil profile. Bioretention systems: An infiltration device consisting of an excavated area that is back-filled with an engineered soil, covered with a mulch layer or erosion control mat and planted with a diversity of woody
and herbaceous vegetation. Storm water directed to the device percolates through the engineered soil, where it is treated by a variety of physical, chemical and biological processes before infiltrating into the
native soil and/or discharges through an underdrain. Class V injection well: Any bored, drilled, or driven shaft, or dug hole that is deeper than its widest surface
dimension, or an improved sinkhole, or a subsurface fluid distribution system. Any infiltration device that has a subsurface pipe distribution system is considered to be an injection well. See ch. NR 815, Wis. Adm. Code or http://dnr.wi.gov/topic/Wells?UIW.html for compliance criteria. Condition value: A value based on NRCS Climate Analysis for Wetlands Tables (WETS Tables) to denote if the month was dry (1), normal (2), or wet (3) compared to the past 20 years of that same month. Using this data, a month is dry when its total rainfall is less than the 30th percentile, wet when its total rainfall exceeds the 70th percentile, and normal when total rainfall is from the 30th to 70th percentile. Construction plan: A map and/or plan describing the built-out features of an individual lot. Coarse sand: Soil material that contains 25% or more very coarse and coarse sand, and <50% any other one grade of sand.
Cultural resources: Historic state resources, including archaeological sites (e.g., Indian mounds, rock art,
logging camps), burial mounds, historic structures, and submerged resources. Design infiltration rate: A velocity (in/hr), based on soil structure and texture, at which precipitation or
runoff enters and moves into or through soil. The design rate is used to size an infiltration device or
WDNR September 2017
1002-TS-14
3
system. Rates are selected based on soil texture or in-field infiltration rate measurements with appropriate correction factors. See also: static infiltration rate, dynamic infiltration rate.
Development site: The entire area planned for development, irrespective of how much of the site is disturbed at any one time or intended land use. It can be one lot or multiple lots.
Direct conduits to groundwater: Wells, sinkholes, swallets, fractured bedrock at the surface, mine shafts, non-metallic mines, tile inlets discharging to groundwater, quarries, or depressional groundwater recharge areas over shallow fractured bedrock. Double-Ring Infiltrometer: A device that directly measures infiltration rates into a soil surface. The Double-
Ring Infiltrometer requires a fairly large test pit excavated to depth of the proposed infiltration device and preparation of a soil surface representative of the bottom of the infiltration area. Dynamic infiltration rate: The infiltration rate accounting for flowing water conditions (multiply static infiltration rate by 0.5), typically used for vegetated swales and filter strips.
Existing grade: Slope of the site prior to modification. Geometric mean: The n root of the product of n values. For example, the geometric mean of 0.5, 0.65,
and 0.71 inches/hour is: √0.5×0.65×0.71 = √0.23075
= 0.61 inches/hr
High groundwater level: The higher of either the elevation to which the soil is saturated as observed as a free water surface in an unlined hole, or the elevation to which the soil has been seasonally or periodically
saturated as indicated by soil color patterns throughout the soil profile. Highest anticipated groundwater level: The sum of the calculated mounding effects of the discharge and the seasonal high groundwater level. Hydrologic condition: For the purposes of this standard, a hydrologic condition (H) is based on the NRCS Climate Analysis for Wetlands Tables (WETS Tables) and calculated as follows: H = (Ct x 3) + (Ct-1 x 2) + (Ct-2) Where: Ct = Condition value for month t Infiltration areas: Areas within a development site that are suitable for installation of an infiltration device. Infiltration basin: An open impoundment created either by excavation or embankment with a flat densely vegetated floor. It is situated on permeable soils and temporarily stores and allows a designed runoff volume to infiltrate the soil.
Infiltration device: A structure or mechanism engineered to facilitate the entry and movement of precipitation or runoff into or through the soil. Examples of infiltration devices include irrigation systems, rain gardens, infiltration trenches, bioretention systems, infiltration grassed swales, infiltration basins, subsurface dispersal systems and infiltration trenches.
Infiltration trench: An excavated trench that is usually filled with coarse, granular material in which storm
water runoff is collected for temporary storage and infiltration. Other materials such as metal pipes and plastic domes are used to maintain the integrity of the trench. Karst feature: An area or surficial geologic feature subject to bedrock dissolution so that it is likely to provide a conduit to groundwater, and may include caves, enlarged fractures, mine features, exposed bedrock surfaces, sinkholes, springs, seeps, or swallets.
Licensed Professional Hydrogeologist: A hydrogeologist licensed by the Wisconsin Department of Safety
and Professional Services.
Licensed Professional Soil Scientist: A soil scientist licensed by the Wisconsin Department of Safety and
Professional Services. Limiting layer: A limiting layer can be bedrock, an aquitard, aquiclude or the seasonal high groundwater
WDNR September 2017
1002-TS-15
table, but it does not include a perched water layer (water above an aquitard) or soil with redoximorphic features. A clayey soil aquitard may exist within a few feet below grade, but still have a suitable layer for
infiltration within 5 feet below the proposed grade. Native soil interface: The surface at which storm water runoff is proposed to infiltrate. This surface is below an engineered soil layer (see Figures 2-4). OSHA: Occupational Safety and Health Administration, a government agency to assure safe and healthy working conditions for working men and women (www.osha.gov). Percent fines: Percentage of given sample of soil which passes through a #200 sieve.
Perched conditions: A soil moisture regime where saturated soil (i.e., wet soil) is located above unsaturated soil (i.e., moist soil).
Permeable pavement system: A pavement system that allows movement of storm water through the pavement surface and into a base/subbase reservoir designed to achieve water quality and quantity benefits. Proposed grade: The proposed final design elevation and grade of the development. This is the top of topsoil, walkways, planting beds, roads, and parking areas. Rain garden: A shallow, vegetated depression that captures storm water runoff and allows it to infiltrate. Regional device: An infiltration system that receives and stores storm water runoff from multiple structures. Infiltration basins are the most commonly used regional infiltration devices.
Soil borings: For the purposes of this standard, soil borings are drilled, bored, cored or dug holes in the
ground to obtain data from an unmixed soil sample, such as from a hollow stem auger or split spoon sampler. Mixed soil samples, such as those from a power auger, are not acceptable. Soil compaction: An increase in bulk density of the soil. The more pressure per unit area exerted on soil, the greater the increase in bulk density, which leads to a decrease in infiltration. Also known as “soil structure degradation.” Soil compaction mitigation: Taking action to decrease bulk density of the soil, which might be
accomplished by a combination of mechanical, vegetative and/or chemical means. Example of compaction mitigation include: deep tilling, deep ripping, soil amendment and establishment of deep-
rooted vegetation. Soil parent material: The unconsolidated material, mineral or organic, from which the solum develops. Solum: The upper part of a soil profile, above the parent material, in which the processes of soil formation are active. The solum in mature soils includes the A and B horizons.
Static infiltration rate: Infiltration rate as measured for standing water. Subsurface dispersal system: An exfiltration system that is designed to discharge storm water through piping below the ground surface, but above the seasonal high groundwater table (subject to the applicable requirements of ch. NR 815, Wis. Adm. Code).
Test pit: An excavation, typically using a backhoe, to examine soil composition, texture, steady state and seasonal high groundwater levels, and bedrock proximity.
Vegetated swale: A constructed storm water conveyance system designed to achieve water quality and
quantity benefits.
WDNR September 2017
1002-TS-16
Figure 1: Site Evaluation for Infiltration Flow Chart
WDNR September 2017
1002-TS-17
Figure 2: Example Bioretention Basin Section
Not to scale
Note 1 NR 151 and SPS 382 require a minimum separation distance from the native soil interface and seasonal high groundwater/bedrock. Note 2 Soil evaluation depth shall extend at least 5 feet below the native soil interface, unless seasonal high groundwater or bedrock is reached. Note 3 Refer to Technical Standard 1004 Bioretention for Infiltration for additional design details. Note 4 Location of infiltration testing is at the native soil interface.
WDNR September 2017
1002-TS-18
Figure 3: Example Bioretention Basin with Underdrain Section
Not to scale
Note 1 NR 151 and SPS 382 require a minimum separation distance from the native soil interface and seasonal high groundwater/bedrock.
Note 2 Soil evaluation depth shall extend at least 5 feet below the native soil interface, unless seasonal high groundwater or bedrock is reached.
Note 3 Refer to Technical Standard 1004 Bioretention for Infiltration for additional design details. Note 4 Underdrain and rock storage is not part of filter layer. Note 5 Location of infiltration testing is at the native soil interface.
WDNR September 2017
1002-TS-19
Figure 4: Example Infiltration Basin Section
Not to scale
Note 1 NR 151 and SPS 382 require a minimum separation distance from the native soil interface and seasonal high groundwater/bedrock. Note 2 Soil evaluation depth shall extend at least 5 feet below the native soil interface, unless seasonal high groundwater or bedrock is reached.
Note 3 Soil amendment, such as compost, may be tilled into the top 1-2 feet of soil.
Note 4 Refer to Technical Standard 1003 Infiltration Basin for additional design details.
Note 5 Location of infiltration testing is at the native soil interface.
WDNR September 2017
1002-TS-20
Attachment 1: Hydrologic Condition Form. This optional table may be used to calculate the hydrologic condition to
fulfil Step A.(4). See next page for example. Month
30% chance will have
Average Monthly Rainfall
Current Year Rainfall
Condition Note 1
Condition Value Note 2
Weight Value Note 5
Product of Condition Value and Weight Value Less than More than
(current)
(current – 1)
(current – 2)
SUM:
Note 5
Note 1 Condition: Where “Current Year Rainfall” < “30% Chance Will Have Less Than,” Condition is Dry Where “Current Year Rainfall” > “30% Chance Will Have More Than,” Condition is Wet Where neither of the above statements (Dry, Wet) is true, Condition is Normal Note 2 Condition Value: Where Condition is Dry, Condition Value is 1 Where Condition is Normal, Condition Value is 2 Where Condition is Wet, Condition Value is 3 Note 3 Given numbers. Note 4 Where the sum is 6 to 9, the hydrologic condition is drier than normal. Ensure the infiltration test site is thoroughly pre-wetted prior to conducting infiltration tests, and consider postponing infiltration tests until normal or
wetter than normal conditions occur. Testing during drier than normal conditions may produce misleading results that may ultimately compromise the integrity of the device. Where the sum is 10 to 14, the hydrologic condition is normal. Infiltration testing during these conditions is recommended. Where the sum is 15 to 18, the hydrologic condition is wetter than normal. Infiltration testing during these conditions is acceptable.
WDNR September 2017
1002-TS-21
Hydrologic condition Example. The following information demonstrates how to obtain and use information to calculate hydrologic condition using WETS tables. Refer to
https://www.wcc.nrcs.usda.gov/climate/wets_defs.html for more information on WETS tables, examples, and definitions, and to https://www.wcc.nrcs.usda.gov/climate/navigate_wets.html for navigating to
climate data, including WETS tables. This example is for Dane County, Charmany Farm, May 2017, using data from 1997-2017; data from USDA Agricultural Applied Climate Information System (AgACIS) is on the following page. Month
30% chance will have Note 1
Average Monthly Rainfall
Note 1
Current Year Rainfall
Note 2
Condition Note 3
Condition Value Note 4
Weight Value Note 5
Product of Condition Value and Weight Value Less than More than
(current) MAY 3.53 5.42 4.65 3.79 Normal 2 3 6
(current – 1) April 3.02 5.18 4.36 4.21 Normal 2 2 4
(current – 2) March 1.51 3.01 2.49 3.15 Wet 3 1 3
SUM:
Note 6
11 (Normal)
`Note 1 Information obtained from WETS tables. Navigate to USDA climate data (see link above), and select (1) Location » nearest the site, (2) Product » WETS, (3) Options » Year Range: past 20 years, Thresholds: 24, 28, 32, (4) View » Go. Note 2 Information obtained from monthly climate summaries. Navigate to USDA climate data (see link above), and select (1) Location » nearest the site, (2) Product » Monthly summarized data, (3) Options » Year Range: current year; Variable: Precipitation; Summary: Sum; Allowable missing days: 1, (4) View » Go. Note 3 Condition: Where “Current Year Rainfall” < “30% Chance Will Have Less Than,” Condition is Dry Where “Current Year Rainfall” > “30% Chance Will Have More Than,” Condition is Wet Where neither of the above statements (Dry, Wet) is true, Condition is Normal Note 4 Condition Value: Where Condition is Dry, Condition Value is 1 Where Condition is Normal, Condition Value is 2 Where Condition is Wet, Condition Value is 3
Note 5 Given numbers. Note 6 Where the sum is 6 to 9, the hydrologic condition is drier than normal. Ensure the infiltration test site is thoroughly pre-wetted prior to conducting infiltration tests, and consider postponing infiltration tests until normal or wetter than normal conditions occur. Testing during drier than normal conditions may produce misleading results that may ultimately compromise the integrity of the device. Where the sum is 10 to 14, the hydrologic condition is normal. Infiltration testing during these conditions is recommended. Where the sum is 15 to 18, the hydrologic condition is wetter than normal. Infiltration testing during these conditions is acceptable.
WDNR September 2017
1002-TS-22
(A) (B) (A) WETS table and (B) current year monthly rainfall output from USDA Agricultural Applied Climate Information System (AgACIS) for use in hydrological determination example, previous page. Data used in the hydrologic condition form is outlined in red. Dates are circled in blue.
WDNR September 2017
1002-TS-23
Horizon Depth in. Dominant Color Munsell Redox Description Qu. Sz. Cont. Color
Texture Structure Gr. Sz. Sh.
Consistence Boundary % Rock Frags.
% Fines Hydraulic App Rate Inches/Hr
Comments:
Horizon Depth in. Dominant Color Munsell Redox Description Qu. Sz. Cont. Color Texture Structure Gr. Sz. Sh. Consistence Boundary % Rock Frags. % Fines Hydraulic App Rate Inches/Hr
Comments:
Name (Please Print) Signature Credential Number
Address Date Evaluation Conducted Telephone Number
Attachment 2:
SOIL AND SITE EVALUATION – STORM
Division of Industry Services P. O. Box 2658 Madison, Wisconsin 53701 Scott Walker, Governor Laura Gutierrez, Secretary In accordance with SPS 382.365, 385, Wis. Adm. Code, and WDNR Standard 1002 Page of Attach a complete site plan on paper not less than 8 ½ x 11 inches in size.
Plan must include, but not limited to: vertical and horizontal reference point
(BM), direction and percent of slope, scale or dimensions, north arrow, and BM referenced to nearest road Please print all information
Personal information you provide may be used for secondary purposes [Privacy Law, s. 15.04(1)(m)]
County
Parcel I.D.
Reviewed by: Date:
Property Owner Property Location Govt. Lot ¼ ¼ S T N R E (or) W
Property Owner’ Mail Address Lot # Block # Subd. Name or CSM #
City State Zip Code Phone Number City Village Town Nearest Road
Drainage area sq .ft acres
Test site suitable for (check all that apply): Site not suitable;
Bioretention; Subsurface Dispersal System;
Reuse; Irrigation; Other
Hydraulic Application Test Method Morphological Evaluation Double Ring Infiltrometer Other: (specify)
Soil Moisture Date of soil borings:
USDA-NRCS WETS Value: Dry =1;
Normal = 2;
Wet = 3.
#OBS. Pit Boring Ground surface elevation. ft. Elevation of limiting factor ft.
#OBS. Pit Boring Ground surface elevation. ft. Elevation of limiting factor ft.
SBD-10793 (R01/17)
1002-TS-24
September 2017
Horizon Depth in. Dominant Color Munsell Redox Description Qu. Sz. Cont. Color
Texture Structure Gr. Sz. Sh.
Consistence Boundary % Rock Frags.
% Fines Hydraulic App Rate Inches/Hr
Comments:
Horizon Depth
in.
Dominant Color
Munsell
Redox Description
Qu. Sz. Cont. Color
Texture Structure
Gr. Sz. Sh.
Consistence Boundary % Rock
Frags.
% Fines Hydraulic App
Rate Inches/Hr
Comments:
Horizon Depth in. Dominant Color Munsell Redox Description Qu. Sz. Cont. Color Texture Structure Gr. Sz. Sh. Consistence Boundary % Rock Frags. % Fines Hydraulic App Rate Inches/Hr
Comments:
Horizon Depth in. Dominant Color Munsell Redox Description Qu. Sz. Cont. Color Texture Structure Gr. Sz. Sh. Consistence Boundary % Rock Frags. % Fines Hydraulic App Rate Inches/Hr
Comments:
#OBS. Pit Boring Ground surface elevation. ft. Elevation of limiting factor ft. Page of
#OBS. Pit Boring Ground surface elevation. ft. Elevation of limiting factor ft.
#OBS. Pit Boring Ground surface elevation. ft. Elevation of limiting factor ft.
#OBS. Pit Boring Ground surface elevation. ft. Elevation of limiting factor ft. Overall Site Comments:
SBD-10793 (R 7/17)
WDNR
Bioretention For Infiltration
(1004)
Wisconsin Department of Natural Resources Technical Standard
I.Definition
A bioretention device is an infiltration device1
consisting of an excavated area that is back-filled withan engineered soil, covered with a mulch layer andplanted with a diversity of woody and herbaceousvegetation. Storm water directed to the devicepercolates through the mulch and engineered soil,where it is treated by a variety of physical, chemicaland biological processes before infiltrating into thenative soil.
II.Purpose
A bioretention device may be applied individually or as part of a system of stonnwater management practices to support one or more of the following purposes:
•Enhance stonn water infiltration•Reduce discharge of storm water pollutants tosurface an_d ground waters•Decrease runoff peak flow rates and volumes•Preserve base flow in streams•Reduce temperature impacts of storm waterrunoff
Ill. Conditions Where Practice Applies
Bioretention devices are suitable for small drainage areas where increased urban storm water pollutant loadings, thermal impacts, runoff volumes and peak flow discharges are a concern and the area is suitable for infiltration. Bioretention devices are best suited to providing on-site stormwater management opportunities adjacent to source areas such as landscaped areas, rooftops, parking lots and streets.
Bioretention devices are not suitable for controlling construction site erosion. These devices will not treat chlorides, and will be damaged by heavy loading of salt-based deicers.
IV.Federal, State and Local Laws
Users of this standard shall be aware of applicable federal, state and local laws, rules, regulations or permit requirements governing bioretention devices. This standard does not contain the text of federal, state or local laws.
V.Criteria
A.Site Criteria
1.A site selected for construction of a bioretention device shall be evaluated in accordance with the WDNR Technical Standard 1002, "Site Evaluation for Stonnwater Infiltration" and shall meet the site requirements of that standard.
2.The following site criteria shall also be met:
a.Private Onsite Wastewater Treatment System (POWTS) - The bioretention device shall be located a minimum of 50 feet from any POWTS and shall not be hydraulically connected to the POWTS dispersal cell or cause negative impacts such as cross contamination.
b.Foundations - The bioretention device shall not be hydraulically connected to building or pavement foundations or cause negative impacts to structures.
c.Slopes- Sloped areas immediately adjacent to the bioretention device shall be less than 20% but greater than 0.5% for pavement and greater than 1 % for vegetated areas to ensure positive flow towards the device.
d.Maximum Drainage Area - The area draining to the bioretention device shall not exceed 2 acres. The drainage area shall not contain significant sources of soil erosion.
Wisconsin DNR 10/2014 Technical Standards are reviewed periodically and updated if needed. To obtain the current version of this standard, contact your local WDNR office or the Standards Oversight Council office in Madison, WI at (608) 441-2677.
1 Words in the standard that are shown in italics are described in Section X Definitions. The words are italicized the first time they are used in the text.
Highway and Structure Construction, Section 645.2.4, Schedule Test B, 2003 edition, or an equivalent approved by the administering authority.
(3)Filter Sock -The openings in the fabricshall be small enough to prevent sandparticles from entering the m1derdrainpipe. The flow rate of the fabric shall becapable of passing water at a rate equalto or greater than the flow rate capacityof the total combined perforations in thew1derdrain pipe. In addition, the fabricshall meet the other requirements ofWisconsin Standards and Specificationsfor Highway and Structme Construction,Section 612.2.8(1-3), 2003 edition, or anequivalent approved by theadministering authority.
f.Clean-out Port -The w1derdrain pipe shallhave a vertical, collllecting standpipe toserve as a clean-out port for the underdrainpipe. The pipe shall be rigid, non-perforatedPVC pipe, a minimum of 6 inches indiameter and covered with a wate1tight capthat is flush with the ground elevation of thedevice.
g.Outlet -The underdrain pipe shall dischargeto an existing drainage system. Examples ofdrainage systems include swales, stormsewers, subsurface dispersal fields andsurface waters.(l)A check valve shall be installed whenbackflow is possible.
(2)Access for maintenance of the checkvalve shall be provided.
9.Sand/Native Soil Interface Layer
a.The interface layer is required when thedesign infiltration rate of the native soil isless than 3.6 inches/hour, as determinedusing DNR Technical Standard 1002, "SiteEvaluation for Stormwater Infiltration."
b.Three inches of sand shall be placed belowthe gravel or sand storage layer, andvertically mixed with the native soil interfaceto a depth of 2-4 inches.
c.Sand shall meet the specifications set forth insection V.B.6.d.(2).
5
10.Design Infiltration Rate - The design infiltration rate of the native soil shall not exceed the rate identified in accordance with WDNR Technical Standard 1002 "Site Evaluation for Stormwater Infiltration".
11.Observation Wells - If there is no w1derdrain, one or more observation wells shall be installed to monitor drainage from the device. There shall be a minimum of one well per 1,000 square feet of �ffective infiltration area. The wells shall be:
a.Located at the center of each section being monitored.
b.A minimum 6 inch diameter slotted PVC pipe, anchored ve1tically to a footplate at the bottom of the bioretention device. The top of the pipe shall be high enough to prevent the entry of water ponded within the infiltration device.
c.Have a secured aboveground cap.
12.Construction Sequencing and Oversight - A person trained and experienced in the construction, operation and maintenance of infiltration devices shall be responsible for construction of the device. The following apply:
1. Construction Site Stabilization - Construction site runoff from disturbed areas shall not be allowed to enter the bioretention device. Runoff from pervious areas shall be diverted from the device w1til the pervious areas have m1dergone.fina/ stabilization.
2.Suitable Weather - Construction shall be suspended during periods of rainfall or snowmelt. Construction shall remain suspended if ponded water is present or if residual soil moisture contributes significantly to the potential for soil smearing, clumping or other forms of compaction.
3.Compaction Avoidance- Compaction and smearing of the soils beneath the floor and side slopes of tl1e bioretention area, and compaction of the soils used for backfill in the soil planting bed, shall be minimized. During site development, the area dedicated to the bioretention device shall be cordoned off to prevent access by heavy equipment. Acceptable equipment for constructing the
WDNR 10/2014
United States Environmental Protection Agency. 2000. Low Impact Development: A Literature Review. Publ. EPA-841-B-00-005. US EPA Low Impact Development Center, Office of Water, Washington, D.C.
Wisconsin Department of Natural Resources, 2004, "Channel Erosion Mat", Technical Standard 1053, http://dnr.wi.gov/topic/stormwater/documents/dnrChannelErosionMat.pdf 11 WDNR 10/2014
Technical Standards are reviewed periodically and updated if needed. To obtain the current version of this standard, contact your local WDNR office or the Standards Oversight Council office in Madison, WI at (608) 441-2677. WDNR September 2018
WISCONSIN DEPARTMENT OF NATURAL RESOURCES
TECHNICAL STANDARD
RAIN GARDEN
1009
DEFINITION
A rain garden is a storm water management practice consisting of a shallow depression planted with a dense cover of vegetation, designed to capture storm water runoff1 from a small drainage area and infiltrate it into the underlying soil.
PURPOSE
A rain garden may be used individually or as part of a system of storm water management practices to support one or more of the following purposes:
(1) Enhance storm water infiltration,
(2) Reduce discharge of pollutants from storm water to surface water,
(3) Increase groundwater recharge,
(4) Decrease runoff peak flow rates and volumes,
(5) Preserve lake levels and base flows in streams,
(6) Reduce temperature impacts of storm water runoff,
(7) Reduce downstream erosion or adverse drainage,
(8) Promote mitigation of runoff closer to its origin, such as a roof downspout.
CONDITIONS WHERE PRACTICE APPLIES
Rain gardens apply to small drainage areas where storm water discharges are a concern, and the soil, site and runoff conditions are suitable for infiltration. Rain gardens are best suited for providing on-site storm water management in landscaped areas that receive runoff from small rooftops which are considered low pollutant risks.
Rain gardens are not suitable for controlling sediment from construction site erosion or treating large areas of impervious surfaces. Rain gardens also have limited applicability where there are clay soils, shallow bedrock, or high groundwater conditions.
This standard contains design limitations for the size of contributing drainage areas (watersheds) and excludes applicability to watersheds where significant sources of sediment or salt-based deicers are present or anticipated. If site conditions or applicable regulations present significant challenges, applying this standard may require the assistance of a professional or the use of other technical standards, such as those designated for storm water infiltration or bioretention.
1 Words in the standard that are shown in italics are described in the Definitions section. The words are italicized the first time they are used in the text.
1009-CPS-2
WDNR September 2018
COMPLIANCE WITH LAW
Users of this standard must comply with applicable federal, state and local laws, rules, regulations or permit requirements governing rain gardens. This standard does not contain the text of federal, state or local laws. The criteria contained in this document may help a user meet the storm water infiltration performance standard under s. NR 151.124, Wisconsin Administrative Code, or as may be required in local storm water ordinances. However, the applicable governing authority makes the final determination of compliance with any regulation.
CRITERIA
Site Criteria
Conduct a site assessment to determine compliance with the following criteria:
(1) Setbacks. Do not hydraulically connect rain gardens with any feature in Table 1. Setbacks are measured from the edge of the ponding area. Confirm minimum setback distances are maintained. If the rain garden is upslope, setbacks may need to be extended depending on site conditions.
Table 1. Minimum Rain Garden Setback Distances
Feature Minimum Setback (feet)
Building foundations (full basement) 10
Building foundation (frost footing) or pavement 5
Wells 8 Note 1
Septic System 5
Note 1 If the proposed rain garden is within 25 feet of a well, a regulatory agent should be consulted regarding potential for well contamination (and to avoid being “hydraulically connected”).
(2) Soil limitations. Confirm a minimum 1-foot vertical separation distance from the bottom of the rain garden to bedrock or high groundwater level. When considering constructing a rain garden in clay soils consider deep rooted plants to enhance infiltration rates (see Table 2). If the Soil Survey shows bedrock is 1-3 feet below the proposed bottom of the rain garden, consult with a
professional to determine if there is risk of sinkhole development.
(3) Slopes. Locate rain gardens on slopes no steeper than 8:1 (horizontal:vertical). Cut and fill
slopes on the perimeter of rain gardens must be 2:1 (horizontal:vertical) or flatter, unless the slope is supported with stone, landscape block, or other retention device.
(4) Drainage area (watershed). Evaluate the area draining to the rain garden based on the rain garden’s proposed location, including rooftops and adjacent landscaped areas. Confirm the total
watershed drainage area does not exceed the maximums specified in the Design Criteria, and that significant sources of sediment or salt-based deicers are not present or anticipated.
(5) Trees. Avoid or minimize damage to roots of desirable trees (generally within dripline).
(6) Erosion/adverse drainage. Direct the outflow/discharge from the rain garden to a stable outlet
that does not cause soil erosion or adverse drainage conditions for other properties.
(7) Utilities. Do not locate rain gardens above buried utilities or within a utility easement without
approval from the applicable authority.
(8) Septic system. Do not hydraulically connect rain gardens to a POWTS dispersal cell or cause
negative impacts such as cross contamination.
Design Criteria
Size of Ponding Area. The minimum size of the rain garden ponding area (bottom of the rain garden, which is called the effective infiltration area, not including the side slopes or berm) depends on the
1009-CPS-3
WDNR September 2018
selected depth of the ponding area, the infiltration rate of the soil, and the percent runoff volume control. The volume of runoff depends on the size of the contributing watershed drainage area, the land use or surface characteristics or both, and the design percentage of runoff to be infiltrated. Use Table 2 to find the appropriate sizing factor used to calculate the rain garden ponding area.
For each ponding depth, the table includes sizing factors for each soil type and corresponding design infiltration rates. It also provides modified sizing factors for three levels of desired runoff volume control: 75%, 90%, and 100% of the average annual rainfall volumes. Selecting the appropriate runoff volume control depends on the goal of the project and applicable regulatory or cost-sharing requirements. Contact local storm water experts for assistance in determining which level to use.
Procedure for design. Determine the minimum ponding surface area (effective infiltration area) of the rain garden by multiplying the drainage area to the rain garden (in square feet) by the appropriate sizing factor from Table 2 (based on the percent runoff volume control, soil type, and ponding depth). The rain garden ponding area includes the bottom of the rain garden, not the side slopes or berm (see Figure 1 and 2).
Rain Garden Design Ponding Area (sq.ft.) = Drainage Area (sq.ft.) x Sizing Factor (from Table 2)
Use the 75% sizing factors for all pervious drainage areas and where runoff from impervious drainage areas travel more than 30 lineal feet on a pervious surface before entering the rain garden.
Table 2. Rain Garden Sizing Factors for Various
Runoff Volume Control Goals, Soil Types and Ponding Depths Note 1
Rain Garden Ponding Depth (inches)
Sizing Factor Based on Soil Type/Design Infiltration Rate and Runoff Volume Control Goal
Clay Loam
(0.15 in/hr)
Silt Loam
(0.30 in/hr)
Loam Note 2
(0.50 in/hr) Loamy Sand
(1.0 in/hr)
Sand
(2.0 in/hr)
Sizing Factors for Goal of 75 Percent Runoff Volume Control Note 3
3-5 0.15 0.11 0.08 0.07 0.04
6-7 0.12 Note 4 0.09 0.07 0.05 0.03
8 0.10 Note 4 0.08 0.06 0.04 0.03
Sizing Factors for Goal of 90 Percent Runoff Volume Control Note 5
3-5 0.23 0.19 0.15 0.12 0.07
6-7 0.18 Note 4 0.14 0.12 0.09 0.06
8 0.15 Note 4 0.12 0.10 0.07 0.05
Sizing Factors for Goal of 100 Percent Runoff Volume Control
3-5 0.44 0.35 0.30 0.23 0.17
6-7 0.35 Note 4 0.30 0.23 0.18 0.13
8 0.25 Note 4 0.23 0.18 0.13 0.11
Note 1 The soil infiltration rates shown in Table 2 only apply to this standard and may not be used for the design of any other stormwater best management practice. Soil infiltration rates in Table 2 were developed from Rawls et.al., 1982 and averages from DNR Technical Standard 1002.
Note 2 This soil category may only be used if an infiltration test is conducted and the soil supports this infiltration rate, or if a soil texture test is conducted by a professional.
1009-CPS-4
WDNR September 2018
Note 3 Designed to meet infiltration performance standards under s. NR 151.124, Wis. Adm. Code for “Moderate imperviousness” land uses (40% to 80% connected impervious surfaces), such as medium and high density residential. The local storm water regulatory authority may have other requirements.
Note 4 Due to drawdown times exceeding 48 hours, turf grass is not appropriate vegetation for rain gardens within this category.
Note 5 Designed to meet infiltration performance standards under s. NR 151.124, Wis. Adm. Code for “Low imperviousness” land uses (less than 40% connected imperviousness), such as parks and low density residential development. The local storm water regulatory authority may have other requirements.
Note 6 Other factors can be used in the design, including evapotranspiration and deep rooted vegetation.
Example 1
Calculate the design ponding area of a rain garden (note the effective infiltration area is equal to the bottom of the pond, and does not include the side slopes) given a pervious drainage area of 5000 sq. ft., 75% runoff control volume (runoff flows 100 ft on a pervious surface before entering the rain garden), 8 inches of ponding, and a loam soil (tested by a professional). The proposed bottom of the rain garden is 12 inches above groundwater. All of the setbacks noted in Table 1 are met.
Solution
The design ponding area of the rain garden (effective infiltration area) = the drainage area x the Table 2 sizing factor for a given soil and pond depth.
Design ponding area = 5000 sq. ft. x 0.06 (Table 2 sizing factor for loam soil, 75% runoff, and 8” of ponding) = 300 sq. ft. Note the design ponding area is equal to the bottom of the rain garden (side slopes are not included).
Drainage Area (watershed). A drainage area contributing runoff to the rain garden may include impervious areas, such as roofs, or pervious areas, such as lawns, or some combination of both. As the size of the drainage area increases, so does the minimum ponding area of the rain garden. The location of the rain garden and nearby grading will determine the size and make-up of the drainage area. The following drainage area limits apply:
(1) The maximum drainage area for impervious surfaces is 3,000 square feet.
(2) The maximum drainage area for all types of surfaces is 5,000 square feet.
Measure roof size using the dimensions of the building plus the overhang for that portion of the roof draining to the rain garden. If the drainage area includes runoff from nearby landscapes, measure the area of contributing landscape and include it in sizing calculations (see criteria above), or divert the runoff from entering the rain garden.
Ponding Depth.
The maximum ponding depth is 8 inches. The design ponding depth is a function of site slope and rain garden dimensions (Table 2). Generally, more steeply-sloped sites or smaller rain gardens will require more depth.
Soil Type/Infiltration Rates.
Conduct an on-site infiltration test or determine soil texture to select the design infiltration rate. Regardless of method, the design infiltration rate may not exceed 2.0 inches/hour.
For on-site infiltration testing, a sample procedure for conducting the test is described in Attachment 1. Professionals may also provide this service using double ring infiltrometers or similar devices.
To establish soil texture, conduct an on-site soil texture analysis or send a soil sample to a lab for texture classification. A sample procedure for conducting an on-site soil texture analysis is contained in Attachment 2. Professionals may also help determine soil textures.
1009-CPS-5
WDNR September 2018
Configuration.
Rain garden components include: ponding area, ponding depth, berm (optional), downslope edge,
planting bed, design overflow (optional), and vegetation. (See Figures 1.1 - 1.3).
Preparing site layout (Figure 1.1), digging basin (Figure 1.2), and completing the berm (Figure 1.3). Note – the effective infiltration area equals the ponding area noted which equals the planting bed area (side slopes are not included).
Berms. On sloped sites or sites with limited soil depth, a small earthen berm may be constructed on the downslope side of the ponding area. This is usually constructed with soils excavated to create the
1009-CPS-6
WDNR September 2018
ponding area (Figure 2), but for shallow soils, clean fill material may be needed for berm construction. Set topsoil aside during the excavation and/or fill process and reuse it on the planting bed and the surface of the berm as a growing medium.
Construct the top width of the berm to be at least 12 inches, and the side slopes to be 2:1 (horizontal:vertical) or flatter, unless the edge of the berm is supported with stone, landscape block, or other retention device. For maintenance purposes, flatter slopes are recommended. Compact the soil in the berm to minimize settling after construction and prevent berm failure. Apply final layer of topsoil, seed and soil stabilizer after compaction.
1009-CPS-7
WDNR September 2018
Downslope Edge. Construct the top of the downslope edge at an elevation needed to retain the design ponding depth for the entire ponding area (a maximum depth of 8 inches). The downslope edge may be the top of a berm or existing grade (Note: Using the existing grade may require exporting the soil excavated for the rain garden ponding area). The downslope edge must direct discharges to a stable outlet that will not create adverse drainage conditions to structures and other properties. If a certain flow path is critical to meet this requirement, design the overflow to meet the requirements listed below.
Protect the downslope edge from erosion before grass is established using soil surface stabilizers such as straw, mulch or erosion control matting.
Design Overflow. For most rain gardens, a small berm can serve as the overflow for large rainfall events. However, it may be desirable to confine the overflow to a particular flow path for proper drainage. For example, the overflow might need to be directed toward a constructed grass swale between properties. To confine the overflow, build the top of the entire berm 3 inches higher than the design ponding depth, leaving a small, level overflow section at the design ponding depth near the desired discharge point. Provide erosion controls at the discharge point as needed. The width of the level overflow section must meet the minimums shown in Table 3.
Table 3. Minimum Width for a Design Overflow in a Rain Garden Berm
Impervious Drainage Area (square feet) Minimum Overflow Width (feet) Note 1
0 – 1000 1.0
1001 –1600 1.5
1601 – 2100 2.0
2101 – 2700 2.5
2701 – 3000 3.0
Note 1 Overflow widths estimated using the Rational Method and peak flows produced by a 100-year/3-minute storm, assuming a runoff coefficient of 0.95 and applying a broad-crested weir outflow to a full rain garden.
Planting Bed. The slope of the planting bed must be as flat as possible, with a maximum slope of 1%. Use original soils for the planting bed. If the excavation exposes subsoils that are difficult to use for planting, over-excavate the area by 2 inches and apply the original topsoil to the new surface.
Soil amendments such as compost may be applied to enhance plant establishment.
Vegetation Plan. Plants are key to stabilizing the rain garden ponding area and encouraging infiltration. To maximize plant growth and survival, develop and implement a vegetation plan, including planting method, timing, sequencing, fertilization, watering and maintenance during the plant establishment period.
Select plants that are hardy for Wisconsin growing conditions. Ensure they are capable of withstanding the site’s soil, sunlight and shade conditions, as well as water inundation and drought cycles associated with rain gardens. Native species, non-native perennials, or cool season turf grasses may be used. The deep roots of many native species will enhance soil infiltration and can better withstand the challenging growing environment inherent to rain gardens. Maximum rain garden depths are more limited for turf grass due to the potential negative impacts of extended draw down times, as shown in Table 2, note 3. Confirm a source of water is available during plant establishment or seed germination.
1009-CPS-8
WDNR September 2018
The following minimum standards apply:
Native Plants and Non-native Perennials
May be planted using plant plugs, prairie sod or seed.
(1) Plant plugs. The minimum planting density is 1 plant per square foot. It is easier to apply mulch to the planting bed before the plant plugs. Watering and weeding between the plant plugs is critical during the establishment phase. Weeding helps prevent the growth of exotic or invasive species. See References for additional recommendations to maximize success rate of plant plugs.
(2) Prairie sod. Follow grower recommendations for plant selection, placement, watering and maintenance. To secure until its root establishment, anchor sod with 6-inch stakes in a minimum 2-foot grid pattern. Compared to seeding and plant plugs, prairie sod requires less maintenance during the establishment period.
(3) Seed. When a rain garden is adjacent to a downspout, seeding is the most difficult method due to potential seed damage and/or loss during heavy rains, and the length of time it takes for native plants to become established (1-2 years). Therefore, downspout discharges must be redirected outside of the rain garden until plants are fully established. The minimum seeding rate depends on the species being planted and must be based on recommendations from the providing nursery based on the rain garden size. For native species, a cover crop such as annual rye grass or oats is required to stabilize the soil while the plants establish their root system. Water daily until the cover crop is well established. Weeding is critical during the establishment phase to prevent the growth of exotic or invasive species. See References for additional recommendations to maximize success rate of the seed.
Note: To improve planting success, aesthetics, and wildlife habitat, a diverse assortment of native species is recommended.
Turf Grass
Rain gardens may be planted with turf grass (except as noted in Table 2 for clay loam soils), using seed or sod as noted below:
(1) Seed. The minimum seeding rates and procedures for establishment and maintenance are described in UWEX publication A3434 Lawn Establishment & Renovation (2000).
(2) Sod. Generally sold in 2-foot by 4-foot sections. Sod must be tamped into place with edges tight and lightly watered daily for 2 weeks.
Woody Vegetation
Rain gardens may also be planted with limited woody vegetation. Do not plant woody vegetation near inflow locations or allow woody species to shade out grasses and forbs. Avoid trees and shrubs where they could obstruct utilities or the line-of-sight triangles at intersections.
Invasive Species
Installing any plant species listed in ch. NR 40.04 Prohibited Category, Wis. Adm. Code (Invasive Species Identification, Classification and Control) is prohibited. Of those, common invaders of rain gardens to be removed immediately include Canada thistle (Cirsium arvense), plumeless thistle (Carduus acanthoides), crown vetch (Coronilla varia), white mulberry (Morus alba), wild parsnip (Pastinaca sativa), and phragmites (Phragmites australis). See Consideration (3) for additional plant species to avoid.
Soil Treatment/Erosion Control. To prevent scour near downspout discharges, install downspout splash pads or line the soil surface with stone or other stable material.
For all design overflows, apply staked erosion matting, stone or other stable material, wrapping up the sides of the flow path. For the remainder of any rain garden that is not sodded, apply one of the following to minimize soil erosion, suppress weed growth, reduce soil compaction during planting and preserve soil moisture until plant growth is established:
(1) Mulch (for plant plugs only). Apply 1 to 2 inches of shredded mulch before planting. The mulch
1009-CPS-9
WDNR September 2018
must be free of foreign material, including other plant material. Push mulch aside to install the plant plugs.
Avoid applying too much mulch, which may negatively affect plant growth. Shredded mulch is more stable than other mulch types, which may be more prone to floating and smothering plants after rain events. Newspaper may be applied to the soil surface prior to the mulch to further suppress weed growth. Mulch can be discontinued at plant maturity provided that the soil surface is fully covered with dense vegetation.
(2) Staked erosion control mat (biodegradable blanket). For plant plugs, apply mat on the surface of the soil prior to planting, and cut through it to install plants. For seeded rain gardens, apply the mat after the seeding and fertilizing is complete. Stake erosion mat to the soil with 6-inch biodegradable staples in a minimum 2-foot grid pattern. Overlap and anchor any joints in the matting in the direction of flow.
Erosion control matting comes in many types and can last 6 months to several years. If the rain garden will be regularly mowed, Class I Urban is recommended as it will degrade more quickly. For native plantings, Class II Type C is recommended since it may stay in place longer.
Construction.
Compaction avoidance. Avoid construction on wet soil as it increases compaction and smear, and reduces infiltration and seed establishment. Avoid excessive foot traffic on the planting bed prior to the application of soil surface stabilizers. Avoid use of heavy construction equipment on the planting bed, especially high-pressure rubber-tired equipment. If possible, cordon off the rain garden area during construction.
Compaction remediation. If compaction is known to have occurred during construction, apply compost to the soil surface and rototill it into the soil as deep as possible to improve infiltration before planting. If after planting, the rain garden does not drain or drains too slowly, allow deep-rooted species time to break through the compacted soil, which may take two to three years. If this does not work, remove all plants and complete the compost and rototill steps. If compaction is deeper than a rototiller can reach, specially-designed deep tillage equipment may also be used to lift and fracture the subsoils without turning over the topsoil.
CONSIDERATIONS
(1) Benefits. Rain gardens planted to native species are especially suitable where other benefits are desired such as shade, windbreak, noise absorption, reduction in reflected light, microhabitat for plants and wildlife, and improved aesthetics.
(2) Planning/Design.
(a) Balancing cut and fill on site will avoid the disposal of excess soil and constructing larger berms than needed.
(b) If outlet pipes or berms larger than those prescribed in this standard are proposed, consult with a professional to consider other designs and additional safety measures.
(c) For large rain gardens, it may be difficult to maintain a flat bottom, especially on sloped sites. If water does not spread over the entire bottom, the effective infiltration area is reduced and drought conditions may form for some of the plants. Consider breaking the rain garden into smaller cells and/or hiring a professional.
(d) Building rain gardens on clay loam soils can be challenging due to the long drain down times. Carefully select plants that can tolerate frequent standing water. Consider using a shallow rain garden option. Deep rooted natives are recommended. If possible, divert inflows away from the rain garden the first year to allow root development, which will improve infiltration over time. Amending the soil with compost, or deep tillage to fracture subsoils may be required. Adding drain tile around the perimeter may also help reduce ponding, but presents
1009-CPS-10
WDNR September 2018
additional challenges for installation, locating an adequate outlet for the tile, and ensuring long-term maintenance of the tile.
(e) Drain down times of less than 24 hours can be advantageous adjacent to airports (to reduce bird habitat).
(3) Plants.
(a) Plants can be selected to simulate a variety of plant communities suitable to the soil type (e.g. plants capable of penetrating clayey soils). Native plant communities should contain a mix of deep-rooted, herbaceous plants; shrubs may also be included.
(b) Consider using plants that offer pollinator habitat, such as the plant list published by the Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP) for gardens and lawns at https://datcp.wi.gov/Documents/PPPGardens.pdf.
(c) Planting plugs or prairie sod is recommended to establish vegetation more quickly. If planting seed, stabilize the seed to prevent it from washing away, and confirm conditions (e.g., water, sunlight) are appropriate to promote its germination.
(d) Consider using plant material from a nursery licensed by DATCP as a Nursery Grower or Nursery Dealer under Wisc. Stats. Ch. 94.10 and WI Admin Code Ch. 21.
(e) Consider the long-term implications of trees within the garden, such as the space it will require when fully grown, possible impacts shade has on ground layer plants, and effects the roots may have on drainage. Avoid planting trees that grow too large or may spread aggressively within or nearby the garden, such as aspens, cottonwood, or boxelder.
(f) Check outside sources, such as gardening centers or professional landscapers, to select the planting distance between trees and shrubs.
(g) Leave stems and seed heads for wildlife cover or bird food. If removing undesired dead plant material, doing so in the spring will allow for insects, including pollinators such as moths and butterflies, to overwinter within the material.
(h) The foliage canopy of plant communities should completely cover the soil planting bed at the end of two growing seasons.
(i) The References section includes two references for plant selection (Shaw and Schmidt, 2003; Bannerman and Considine, 2003). It is recommended that experienced individuals be consulted to assist with vegetation selection and establishment.
(j) Avoid installing plant species listed in ch. NR 40.04 Prohibited or Restricted Categories, Wis. Adm. Code (Invasive Species Identification, Classification and Control).
(k) If the rain garden is intended to maintain plant diversity, avoid installing the following plant species which are common invaders of rain gardens and may overtake or degrade the intended plant diversity. Remove these species if found:
1. Reed canary grass (Phalaris arundinacea)
2. Quack grass (Agropyron repens)
3. Bull thistle (Cirsium vulgare)
4. Burdock (Arctium spp.)
5. Wild carrot (Daucus carota)
6. Sweet clover (Melilotus spp.)
7. Cattails (Typha spp.) not only can outcompete intended native plant diversity, but are also an indicator that the rain garden remains too wet.)
8. Canada goldenrod (Solidago canadensis)
9. Tall goldenrod (Solidago altissima)
1009-CPS-11
WDNR September 2018
10. Orange daylily (Hemerocallis fulva)
11. Miscanthus grass (Miscanthus spp.)
12. Giant ragweed (Ambrosia trifida)
13. Common ragweed (Ambrosia artemisiifolia)
14. Boxelder (Acer negundo)
15. Cottonwood (Populus deltoides)
PLANS AND SPECIFICATIONS
Prepare plans and specifications for each specific field site in accordance with the criteria of this standard
and describe the requirements for applying the rain garden to achieve its intended use.
Specify the materials, construction processes and sequence, location, size, and elevations of all
components of the rain garden to allow for certification of construction upon completion in the plan.
Include the following on the plans:
(1) A vicinity map showing the drainage area, north arrow, rain garden location, and flow paths to and from the rain garden.
(2) Limits of construction and areas to avoid compaction.
(3) A plan view of the rain garden showing the existing and proposed elevation contours, shape,
dimensions, and flow paths to and from the rain garden.
(4) A long direction cross-section view of the rain garden showing depth of cut, side slopes, height of
the berm and overflow. Set a temporary benchmark from which to measure cuts and fills.
(5) A short direction cross-section view of the rain garden, showing depth of cut, side slopes, height
of the berm and overflow.
(6) A vegetation plan (including plant names and planting locations).
Include the following with the specifications:
(1) A description of the contractor’s responsibilities (if contracted).
(2) Additional details relating to vegetation, including:
(a) Plant material listing (names, quantities, etc.).
(b) Site preparation needed to establish and grow selected species.
(c) Planting period, care, and handling of the planting materials to confirm that they have an
acceptable rate of survival, including initial weeding and watering responsibilities.
(d) Vegetation warranty period.
OPERATION AND MAINTENANCE
Prepare a maintenance plan with the following elements (see Table 4 example):
(1) Inspection. A plan to inspect the rain garden a minimum of three times per growing season to
remove nuisance or invasive plants and identify problems with excess moisture, soil erosion, berm settling or failure of any other component.
(2) Plants and weeds. Cut and remove nuisance or invasive species, remove excessive dead plant material annually, and replace desired species that may have died in significant numbers.
(3) Erosion control and berm settling. Stabilize eroding soil and repair damage or settling that may occur on the berm if it affects the ponding area or discharge flow path.
1009-CPS-12
WDNR September 2018
(4) Compaction. If the rain garden retains surface water for greater than 72 hours, soil compaction mitigation may be needed. Soil compaction mitigation includes taking action to decrease bulk density of the soil, which might be accomplished by a combination of mechanical, vegetative and/or chemical means. Examples of compaction mitigation include: deep tilling, deep ripping, soil amendment and establishment of deep-rooted vegetation. If turf grass is currently present, switch to deep-rooted native species.
Note: The local regulatory authority may require the maintenance plan to be recorded on the property deed with provisions for access by the regulatory authority for inspection and enforcement purposes.
Hire or train individuals who are able to identify all of the plant species that were planted in the rain garden at all stages of life as well as common weeds and invasive plants. These individuals should also be knowledgeable about effective control methods for common weeds.
It is not recommended to use a rain garden for snow storage since snow is often associated with deicers and other sediment and debris, which will damage the plants and soil.
Table 4. Typical Maintenance Activities for Rain Garden Areas
ACTIVITY FREQUENCY
Inspect rain garden to remove nuisance or invasive plants and identify problems with excess moisture, soil erosion, berm settling or failure of any other component
At least three times per growing season
Water plants As needed for several weeks after planting, and during drought conditions thereafter
Monitor water level after a large rainfall to ensure drainage As needed, especially during the first year
Remove nuisance or invasive plants As needed per inspections
Re-plant void areas As needed per inspections
Treat diseased trees and shrubs As needed per inspections
Repair eroded areas and any berm damage or settling As needed per inspections
Remove trash and debris As needed per inspections
Remove excessive dead plant material Annually (spring recommended)
REFERENCES
ASCE, 1992, ASCE Manuals and Reports of Engineering Practice No. 77, Design and Construction of Urban Stormwater Management Systems.
Bannerman, R. and E. Considine. 2003. Rain Gardens: A How-to Manual for Homeowners. University Wisconsin Extension Publication GWQ037 or Wisconsin Department of Natural Resources Publication PUB-WT-776 2003.
Ch. NR 40, Wis. Adm. Code, https://docs.legis.wisconsin.gov/code/admin_code/nr/001/40
1009-CPS-13
WDNR September 2018
Ch. NR 151, Wis. Adm. Code, https://docs.legis.wisconsin.gov/code/admin_code/nr/100/151
Claytor, R.A. and T. Schueler. 1996. Design of Stormwater Filtering Systems. Center for Watershed Protection, Silver Spring, Maryland.
Davis, A.P., M. Shokouhian, H. Sharma, C. Minami, and D. Winogradoff. 2003. Water quality improvement through rain garden: Lead, copper and zinc removal. Wat. Envir. Res., Vol 75(1), 73-82.
Davis, A.P., M. Shokouhian, H. Sharma, and C. Minami. 1981. Laboratory study of biological retention for urban stormwater management. Wat. Envir. Res., Vol 73(1), 5-14.
Hunt, B. 2003. Rain garden Use and Research in North Carolina and Other Mid-Atlantic States. The NCSU Water Quality Group Newsletter, May, 2003. North Carolina State University and A&T State University Cooperative Extension.
Hunt, B. Designing Rain Gardens (Bio-Retention Areas) Urban Waterways Series Publication, North Carolina State University and A&T State University Cooperative Extension.
Livingston, E.H., E. Shaver, J. Skupien and R. Horner. 1997. Operation, Maintenance and Management of Stormwater Management Systems. Watershed Management Institute, Ingleside, Maryland.
Nowak, M. 2012. Birdscaping in the Midwest – A Guide to Gardening with Native Plants to Attract Birds.
Itchy Cat Press, Blue Mounds, Wisconsin.
Prince George’s County Department of Environmental Resources. 1993. Design Manual for Use of Rain garden in Storm Water Management. Division of Environmental Management, Watershed Protection Branch. Landover, MD.
Prince George’s County Department of Environmental Resources. 1999. Low-Impact Development Design Strategies: An Integrated Design Approach. Prince George’s County, Maryland.
Prince George’s County Maryland. Prince George’s County Rain garden Manual, November 2001 (revised December, 2002).
Rawls, W.J., Brakensiek, D.L., and Saxton, K.E., 1982. Estimating Soil Water Properties, Transactions of the ASAE, 1316-1320.
Roth, S. 1997. Natural Landscaping – Gardening with Nature to Create a Backyard Paradise. Rodale
Press, Inc., Iowa.
Schueler, T. and H. K. Holland. 2000. Rain garden as a Water Quality Best Management Practice, in The Practice of Watershed Protection. Center for Watershed Protection, Ellicott City, Maryland.
Shaw, Daniel and R. Schmidt. 2003. Plants for Stormwater Design. Minnesota Pollution Control Agency, St. Paul, MN.
Steiner, Lynn M. 2007. Landscaping with Native Plants of Wisconsin, Voyageur Press.
Stormwater Management Manual for Western Washington, Volume 5, Runoff Treatment BMPs, prepared by the Washington Department of Ecology, August 2001, Publication No. 99-15.
United States Environmental Protection Agency. 1999. Storm Water Technology Fact Sheet: Rain garden. Publ. EPA-832-F-99-012. Office of Water, Washington, D.C.
United States Environmental Protection Agency. 2000. Low Impact Development: A Literature Review. Publ. EPA-841-B-00-005. US EPA Low Impact Development Center, Office of Water, Washington, D.C.
Wisconsin Department of Natural Resources, 2004, “Channel Erosion Mat”, Technical Standard 1053, https://dnr.wi.gov/topic/stormwater/documents/ChannelErosionMat1053.pdf.
Woelfle-Erskine, Cleo and Apryl Uncapher. 2012. Creating Rain Gardens – Capturing the Rain for Your
Own Water -Efficient Garden. Timber Press, Portland, Oregon, 203 pp.
1009-CPS-14
WDNR September 2018
DEFINITIONS
Adverse drainage: Where runoff causes negative impacts to nearby properties or structures, including but not limited to roads, sidewalks, yards, driveways, basements, septic systems, wells and utilities.
Berm: Mounding of soil at the lowest side of the rain garden to retain a specified depth in the ponding area. A berm may include an overflow area.
Bedrock: Digging is prevented due to a consolidated rock material, or weathered rock material covering 50 percent or more of the soil layer.*
Bottom of the rain garden to bedrock: The lowest elevation of the soil surface inside the rain garden after final grading and the application of topsoil.
Double ring infiltrometer: A device used to measure the infiltration rate of the soil by saturating the soil around the area being measured.*
Drainage Area (watershed): The area (square feet) of roof top or other surface that is draining to, or contributing runoff to, the rain garden.*
Effective Infiltration Area: The area (square feet) of the bottom of the rain garden that is used to infiltrate runoff, not to include the area used for berms or side slopes.
High groundwater level: The higher of either the elevation to which the soil is saturated as observed as a
free water surface in an unlined hole, or the elevation to which the soil has been seasonally or periodically
saturated as indicated by soil color patterns throughout the soil profile.*
Hydraulically connected: Two entities are said to be hydraulically connected if a surface or subsurface
conduit exists between the two such that water is transmitted from one entity to the other.*
Infiltrate or Infiltration: Entry and movement of precipitation or runoff into or through the soil. It includes
water that may be subsequently evaporated or transpired by plants.
Infiltration Test: A test that measures how fast water is able to infiltrate the soil (measured in inches per
hour).*
Percent runoff volume control: The percentage of the total average annual runoff volume designed to be
infiltrated in the rain garden.
Planting bed: The bottom of the rain garden. The area (square feet) used for planting.
Ponding area: The area of the bottom of the rain garden, not including the side slopes or berm.
Ponding depth: The distance (in inches) between the bottom of the planting bed (soil surface) and the top
of the berm or design overflow area, whichever is less.
Prairie Sod: A farm-grown sod using prairie seed.
Private onsite wastewater treatment system (POWTS): A private onsite wastewater treatment system, commonly referred to as a septic system. Designed to treat wastewater from residential homes and
businesses where a connection to a municipal sewer system is not available.*
Runoff: Rain water or melting snow flowing off a rooftop or ground surface.
Soil Survey: Published by the USDA-Natural Resources Conservation Service (NRCS) and available online (.pdf) for every county in Wisconsin, or through a web-based geographic information system, such
as through NRCS at: https://websoilsurvey.sc.egov.usda.gov/App/WebSoilSurvey.aspx .
Soil texture analysis: The look and feel of a soil; it is determined by the size and type of particles that
make up the soil (see Attachment 2 for details).*
* These items may require analysis by a professional to determine compliance with this standard.
1009-CPS-15
WDNR September 2018
Attachment 1:
Conducting a Simplified Infiltration Test
This attachment describes a means of conducting a simplified infiltration test.
MATERIALS:
(1) A metal coffee can or hard plastic cylinder (min 6 inches long and 4 inches in diameter, this can be a can with tops removed or a section of pipe)
(2) Plastic or metal lawn edging (min 6 inches high and 7 feet long)
(3) Duct tape
(4) Hand sledge or hammer
(5) Wood board or block (about an inch longer than the diameter of cylinder)
(6) Water (rainwater or distilled water is preferred)
(7) Stopwatch or timer
(8) Clipboard, paper and a pen for recording information
(9) Permanent marker that can be used to write on the cylinder
(10) Ruler or tape measure (intervals of 1/10 of an inch and at least as long as the cylinder)
(11) Tarp at least 6 feet by 6 feet with weights for ballast (if rain is expected over next 24 hours)
Step 1. Prepare the Cylinder
(1) If a can is used as the cylinder, cut out the bottom and clean.
(2) Mark the outside of the cylinder at 3 inches from the edge that will be driven into the ground.
(3) Mark the inside of the cylinder at 0.5, 1.0, and 3.0 inches from the bottom edge (to be driven into the ground).
(4) Measure the length of the cylinder.
Step 2. Prepare a Circular Flat Bottomed Hole
(1) Dig a circular, flat-bottomed hole with a diameter of 2 feet and a depth about 3 inches above the
planned bottom of the rain garden.
(2) Remove loose material from the bottom of the hole.
(3) Line the 2-foot diameter hole with the edging, burying it 2 inches. Tape the edging at the joint where the ends meet (Figure 3).
Step 3. Position the Cylinder
(1) Place the cylinder in the center of the hole (Figure 3).
(2) Lay the wood board or block on the top of the cylinder.
(3) Drive the cylinder 3 inches into the bottom of the 2 ft. diameter hole, such that the bottom of the cylinder is at the bottom of the proposed rain garden, keeping it perpendicular to the ground. The three-inch mark should be at the bottom of the hole (Figure 3).
1009-CPS-16
WDNR September 2018
(4) Remove soil from the inside of the cylinder (see Figure 3) down to the bottom of the cylinder (3 inches).
Step 4. Wet the Soil
(1) Fill the area between the cylinder and lawn edging with water to a depth of about 3 inches, being careful not fill above the cylinder. Fill the cylinder to a depth of 3 inches. The cylinder will be full to the level of the bottom of the 2-foot diameter hole. Note that water depths are measured from the bottom of the cylinder.
(2) Leave the cylinder for at least 24 hours (if rain is expected, cover the site with a tarp).
Step 5. Return to the Site
(1) If there is still any water in the cylinder after 24 hours, the infiltration rate is less than 0.12 inches per hour (3 in. / 24 hrs. = 0.12 in. / hr.), and the site is not suitable for a rain garden. Otherwise, if all water has infiltrated and there is no water in the cylinder after 24 hours, go to step 6.
Step 6. Continue the Test
(1) Refill the area between the cylinder and lawn edging to a depth of 3 inches, being careful not fill above the cylinder.
(2) Pour the water into the cylinder up to the 1-inch mark.
(3) Start the timer immediately.
(4) Return to the cylinder in 30 minutes.
(a) If the cylinder is empty, the infiltration rate is greater than or equal to 2.0 inches per hour (1.0 inch / 0.5 hour = 2.0 inches / hour)
(b) If the cylinder is not empty, but the water depth is less than or equal to ½ inch, measure
the water depth to the nearest 1/10 inch from the bottom of the cylinder.
1. Example infiltration rates:
a. If the depth of water in the cylinder is 0.5 inches, that means 0.5 inches of water has infiltrated in 30 minutes, and the infiltration rate is 1.0 inch per hour (0.5 inch / 0.5 hour).
b. If the depth of water in the cylinder is 0.2 inches, that means 0.8 inches of water has infiltrated in 30 minutes, and the infiltration rate is 1.6 inches per hour (0.8 inch / 0.5 hour)
(5) If the depth of water in the cylinder is greater than or equal to the ½-inch mark, refill the area between the cylinder and lawn edging to a depth of 3 inches being careful not to fill above the
cylinder, and return to the cylinder in 30 minutes (1 hour after the timer was started).
(a) If the cylinder is empty, the infiltration rate is 1.0 inches per hour (1.0 in. / 1.0 hr.).
(b) If the cylinder is not empty, but the water depth is less than or equal to the ½-inch mark,
measure the water depth to the nearest 1/10 inch.
1. Example infiltration rates:
a. If the depth of water in the cylinder is 0.5 inches, the water has dropped 0.5 inches, and the infiltration rate is 0.5 inches per hour (0.5 in. / 1 hr.)
b. If the depth of water in the cylinder is at 0.2 inches, the water has dropped 0.8 inches in an hour, and the infiltration rate is 0.8 inches per hour (0.8 in. / 1 hr.)
1009-CPS-17
WDNR September 2018
(6) If the depth of water in the cylinder is greater than or equal to the ½-inch mark, refill the area between the cylinder and lawn edging to a depth of 3 inches being careful not to fill above the cylinder, and return to the cylinder in 60 minutes (2 hours after the timer was started).
(a) If the cylinder is empty, the infiltration rate is 0.5 inches per hour (1.0 in. / 2 hr.)
(b) If the cylinder is not empty, but the water level is less than or equal to the ½-inch mark,
measure the water depth to the nearest 1/10 inch.
1. Example infiltration rates:
a. If the depth of water in the cylinder is at 0.5 inches, the infiltration rate is 0.25 inches per hour (0.5 in. / 2 hr.)
b. If the depth of water in the cylinder is 0.2 inches, the water has dropped 0.8 inches, and the infiltration rate is 0.4 inches per hour (0.8 in. / 2 hr.)
(c) If the depth of water in the cylinder is above 0.7 inches, the infiltration rate is less than 0.15 inches per hour (0.3 in. / 2 hr.), and the site is not suitable for a rain garden.
FIGURE 3. Creating the simplified soil infiltration test.
1009-CPS-18
WDNR September 2018
Attachment 2:
Identifying Soil Texture
This attachment provides guidance on assessing soil texture by feel. This method is intended to be used to select appropriate rain garden sizing criteria.
City of Oshkosh Stormwater Quality Management Plan
C-1
Oshkosh SWMP Final.docx
Appendix C: Draft Memorandum of Understanding
1. UW-Oshkosh Intergovernmental Agreement
2. Winnebago County Memorandum of Understanding
INTERGOVERNMENTAL COOPERATION AGREEMENT
CITY OF OSHKOSH AND STATE OF WISCONSIN,
UNIVERSITY OF WISCONSIN – OSHKOSH
WHEREAS, the City of Oshkosh (“City”) operates a storm sewer disposal system
and has been designated by the State Department of Natural Resources as an MS4 (Municipal
Separate Storm Sewer System) provider of services; and
WHEREAS, the University of Wisconsin – Oshkosh (“University”) is treated under
the law as a municipal provider of storm water disposal services with respect to stormwater
generated on and dispersed from the campus of the University and is similarly designated; and
WHEREAS, the City and University storm water disposal systems are interconnected;
and
WHEREAS, the City has the ability to fulfill the responsibilities of managing both its
systems and that of the University in a manner consistent with laws and regulation applicable
thereto and the University desires to avail itself of said services from the City.
NOW, THEREFORE, THIS AGREEMENT.
1. Authority
This agreement is entered into by the parties hereto pursuant to the authority vested in
each of them under §66.0301, Wis. Stats., pursuant to which any city in conjunction with the
state and any department thereof may jointly perform or one on behalf of the other may
perform and the other may receive services or jointly exercise any powers or duties authorized
by law. Each of the parties hereto is authorized to engage in stormwater disposal services
pursuant to approval by the State Department of Natural Resources (“DNR”) and each
currently owns and operates a stormwater disposal system, subject to the oversight of and
approval by the DNR.
2. Functions to be Performed by the City on behalf of the University
Through this agreement, the City agrees to provide Stormwater Utility service to the
University in a manner consistent with the service it provides to other ratepayers.
Furthermore, the City agrees to perform the following stormwater related services on behalf
of the University:
a. Public Education Website
The City will maintain its website providing education about stormwater effects
and conservation efforts. The University may link to the City page to provide
educational information to University website users as well. The City shall not,
under this agreement, be obligated to provide additional information on its website at
the request of the University.
Intergovernmental Agreement Page 1 of 4
L:\library\Dept\WAT_RES\Projects on Other Servers\60268145 - Oshkosh SWMP\DNR
Comments\Attachments\Attachment 5 - UWO MOU\OSH-UW Oshkosh_StormWaterMOU.doc
b. Erosion Control Inspections
The City will provide erosion control inspections of all University active building
sites and report inspection results to the Director of Facilities Management at UW-
Oshkosh for follow up. The City shall not be responsible for any follow up action.
Inspection schedule shall be worked out on a project by project basis.
c. Outfall Inspections
The City will perform annual inspections of the major storm sewer system
outfalls on the Fox River adjacent to UW Oshkosh, and to which UW Oshkosh is a
major contributor. A University employee will accompany the City employee if
available. All inspection reports and follow up work required will be submitted to
the University. The University shall be responsible for the follow up work that is
required.
d. Storm Sewer Inspections
The City will do a comprehensive inspection of the main storm sewer system
components as shown in Exhibit A. Inspections shall occur at a minimum of once
every 5 years. Any repairs that are needed will be performed by the University. The
University will continue to do its own visual inspections of the system semi-annually
as required by their NOI (notice of intent).
e. Pond Inspections
The City will inspect all University owned and operated ponding facilities within
the same rotation as all other City ponds. Currently the ponds are on a 5 year
inspection rotation. All design information needed to perform adequate inspections
shall be provided by the University to the City. Without such information, the
inspections may not cover all required components. Any uncovered items shall be
the responsibility of the University. The ponds to be inspected by the City are also
highlighted in Exhibit A.
f. Storm Sewer System Map
The City will create and maintain a digital map of the University storm sewer
system. The University shall provide to the City any information it obtains about its
storm sewer system. Any corrections and/or updates shall be submitted to the City.
The City will prepare a map submittal for the DNR on an annual basis. The City will
update the map as appropriate based on storm system inspection results. The City
will only be responsible for the completeness of the map to the extent of the
information provided by the University.
3. Functions to be performed as a joint effort between the City and University
a. Public Educational Efforts
The City shall provide the University with any informational brochures already
produced. The University has a stormwater logo contest planned; the City will
assist this effort. The end result will be a logo that can be used by the City and
University in stormwater efforts. The City and University will work together in
locating and promoting generic public service announcements regarding stormwater
management. These public service announcements will be aired on the City cable
station, Channel 16 as well as the University cable station, Channel 19.
b. Community Outreach
c. Annual Public Meeting
Intergovernmental Agreement Page 2 of 4
L:\library\Dept\WAT_RES\Projects on Other Servers\60268145 - Oshkosh SWMP\DNR
Comments\Attachments\Attachment 5 - UWO MOU\OSH-UW Oshkosh_StormWaterMOU.doc
The University will organize and hold its own annual public meeting. The City
will provide a representative at that meeting to answer any questions that may arise.
4. Obligation of the University to the City
The University agrees to purchase Storm Water Utility services from the City throughout
the term of this agreement. The University’s fee to purchase this service shall be in
accordance with established rules, rates and ordinances of the City. The stormwater utility fee
is a runoff based fee, which has been adjusted for the University based on the actual land uses
of the University. Monthly rates to the university are established based on estimates of runoff
produced and the current fee per runoff unit, consistent with all other ratepayers receiving
service from the Storm Water Utility.
In exchange for the willingness of the City to perform the functions identified in 2., above,
the University agrees that it shall transfer to the City, during the term of this Agreement, all
pollution control credits needed to help meet the 20% and 40% total suspended solids removal
requirement. The City acknowledges that this is adequate consideration in exchange for the
duties which it is willing to perform under this Agreement. In addition, the University will
continue to pay stormwater utility fees to the City at the current contribution rate.
5. Separate Maintenance and Operation to be Continued
This Agreement shall not be interpreted as an understanding between the parties hereto
that the City will assume the responsibility for the ownership and operation of the
University’s stormwater disposal system. Each party hereto shall separately administer and
operate its system, despite interconnections, subject only to the City’s willingness to provide
services in relationship thereto on behalf of the University. To this extent, the University
acknowledges that it shall remain solely responsible to maintain roof drains, catch basins, and
proprietary devices located on its campus, which direct stormwater into its disposal system.
In addition, the University will organize its own street sweeping, fleet maintenance, and snow
and ice removal program. The University will also conduct semi-annual visual inspections of
their storm water system in addition to the more in depth inspection the City will perform
every 5 years. The City and University will each produce their own annual reports for the
DNR. For items the City has performed for the University, the City will provide the
University documentation needed to complete the annual report.
6. Term of Agreement
This Agreement shall continue for a term of ten years from and after the 1st day of the
month next following the date of execution hereof by the parties hereto. Said term shall be
shortened only in the even that the DNR determines that it is in volition of state law or
regulations or by mutual agreement of both parties affected by this Agreement.
7. Miscellaneous Terms
a. The laws of the State of Wisconsin shall govern this Agreement.
Intergovernmental Agreement Page 3 of 4
L:\library\Dept\WAT_RES\Projects on Other Servers\60268145 - Oshkosh SWMP\DNR
Comments\Attachments\Attachment 5 - UWO MOU\OSH-UW Oshkosh_StormWaterMOU.doc
b. Notices under this Agreement shall be provided, personally or by US Mail to the
following representatives of the parties hereto:
City of Oshkosh Mr. David Patek, P.E.
Public Works Director
215 Church Ave
P.O. Box 1130
Oshkosh, WI 54903-1130
(920) 236-5065
University Mr. Richard Wells
Chancellor
800 Algoma Blvd
Oshkosh, WI 54901
(920) 424-0200
c. The City is not, by assuming the duties imposed upon it under this Agreement,
taking on or absorbing any fiscal responsibility of the University to operate its
stormwater disposal system. Each party shall remain responsible for its own costs
of operation, maintenance and repair. However, to the extent that portions of the
University stormwater disposal system are drained into the City system and to the
extent that portions of the City stormwater disposal system drain into the University
system, each agrees to make such accommodations to the other in terms of
operations and cost as may be deemed equitable under the circumstances.
Dated this ____ day of ________________, 2010.
CITY OF OSHKOSH UNIVERSITY OF WISCONSIN-OSHKOSH
By:________________________ By:_______________________________
Intergovernmental Agreement Page 4 of 4
L:\library\Dept\WAT_RES\Projects on Other Servers\60268145 - Oshkosh SWMP\DNR
Comments\Attachments\Attachment 5 - UWO MOU\OSH-UW Oshkosh_StormWaterMOU.doc
MEMORANDUM OF UNDERSTANDING
Between
The City of Oshkosh Department of Public Works
and
The Winnebago County Highway Department
I. PURPOSE
The purpose of this Memorandum of Understanding (Memo) is to define the working
relationship between the City of Oshkosh Department of Public Works and the
Winnebago County Highway Department with respect to stormwater management.
Specifically, this Memo will clarify the collaborative roles and responsibilities of the
two agencies as it relates to the Wisconsin Department of Natural Resources
(WDNR) Municipal Separate Storm Sewer System (MS4) General Permit [herein
after referred to as MS4 Permit] activities.
II. BACKGROUND
1. The WDNR has issued separate MS4 Permits to both the City of Oshkosh and to
Winnebago County [under the Wisconsin Pollutant Discharge Elimination System
(WPDES) requirements in accordance with ch.283, WI Stats. and subch. I of ch.
NR216, Wis. Adm. Code] for stormwater management.
2. A requirement of the MS4 Permit is to develop a pollutant loading analysis for the
municipalities’ MS4 utilizing a stormwater computer model.
3. The MS4 Permit also requires communities to achieve 20% and 40% total
suspended solids (TSS) reduction from the municipalities’ MS4 stormwater
discharge by roughly 2008 and 2013, respectively.
4. Winnebago County, currently, owns six (6) county road right-of-ways (ROW)
located within the City of Oshkosh (County Roads A, E, K, Y, I, and Waukau
Avenue). [ROW includes county road surfaces, shoulder, swales, and additional
area within the ROW.]
5. Currently, four (4) of the six (6) county roadways within the City of Oshkosh (see
attached Table 1.) were designed and constructed to drain stormwater directly into
the City of Oshkosh storm sewer, which underlies the county road ROW. As such,
stormwater generated within the county road ROW (and potentially any additional
associated drainage areas) are directed to curb inlets that are connected to City of
Oshkosh storm sewer. The City of Oshkosh owns the storm sewer system
underlying the Winnebago County ROW at these locations.
6. Based on the MS4 Permit, stormwater runoff generated within the county road
ROW would be required to achieve the 20%/40% TSS reductions prior to the
stormwater entering the City of Oshkosh storm sewer. However, the WDNR
indicates that if the stormwater from the county road ROW would receive the
required 20% and 40% TSS removals at another location (in this case, other than
the curb inlets) prior to discharging to waters of the state, this would meet the
MS4 Permit requirements.
P 1/3
III. AGREEMENT
1. CITY of OSHKOSH RESPONSIBILITIES
The City of Oshkosh agrees to:
a. Perform operation and maintenance on the City of Oshkosh owned stormwater
systems [ie. storm sewer (and any other City owned utility/structures)] underlying
the County ROW and/or serving to drain stormwater runoff from the county road
ROW. [Illicit connections to City-owned stormwater systems would be the
responsibility of the City of Oshkosh.]
b. Develop a pollutant loading analysis for the county road ROWs listed in Table 1.
using a stormwater computer model in accordance with all WDNR requirements;
c. Accept and address (attenuate) stormwater runoff from the Winnebago County
ROWs listed in Table 1. to meet all current (20%/40% TSS reductions) and any
future stormwater requirements (further TSS reductions and/or other
parameters/pollutants) dictated or enacted by the United States Environmental
Protection Agency (EPA) and/or the state of Wisconsin;
d. Provide Winnebago County with any and all necessary records, reports, results,
data, or any documentation regarding stormwater management/MS4 permitting
for the county road ROWs listed within this Memo;
e. The City of Oshkosh will not impose any fees and/or request monies from
Winnebago County for any of these or other associated activities.
2. WINNEBAGO COUNTY RESPONSIBILITIES
Winnebago County agrees to:
a.) Perform operation and maintenance on the county owned ROW as long as the
ROWs are owned by Winnebago County; maintenance includes the following:
i. Repair and maintenance of roadways including road surfaces and/or road
base,
ii. Snow and ice removal from the roadways,
iii. Street sweeping of road surfaces and appropriate disposal of sweepings,
iv. Repair and maintenance of road shoulders, swales and county owned
ROW;
b.) Prepare, monitor, and implement illicit discharge procedures for the county road
ROW listed herein;
c.) Prepare, maintain, and implement a pollution prevention plan and procedures for
the county road ROW listed herein;
d.) Provide information and education activities to Winnebago County Highway
personnel regarding these roadways;
e.) Provide the City of Oshkosh with any and all necessary records, reports, results,
data, or any documentation regarding stormwater management/MS4 permitting of
the road segments listed within this Memo.
P 2/3
IV. PROVISIONS
1. The provisions of this Memo are effective upon both parties signatures and shall
continue in effect indefinitely.
2. This Memo covers all future or expanded MS4 Permit boundaries (Urbanized
Area) and/or all future county road ROW constructed to route stormwater to City
of Oshkosh stormwater systems.
3. This Memo and any supplements contained within may be amended at any time
by mutual consent of the parties.
4. Either party may terminate this Memo by giving thirty (30) days prior notice in
writing to the other party.
V. ADOPTION
The foregoing memorandum of understanding has been adopted by each of the
parties thereto, duly recorded in the official proceedings of each, and as attested by the
signatures affixed below.
For the City of Oshkosh Department of Public Works:
_____________________________________________________________________
David Patek, City of Oshkosh, Department of Public Works Date
For the Winnebago County Highway Department:
_____________________________________________________________________
John Haese, Winnebago County Highway Commissioner Date
P 3/3
Table 1. Winnebago County Road ROW within the City of Oshkosh*,
MS4 Modeling and Stormwater Treatment Responsibilities,
Memorandum of Understanding Between the City of Oshkosh and
Winnebago County.
OSHKOSH RESPONSIBILITES
County Road A (North Shore Dr., Harrison St.)
from County Road Y to Libbey Ave. (approx. 2.6 miles)
County Road E (Witzel Ave.)
from Barton Rd. to Koeller St. (approx. 1.0 miles)
County Road K (20th Ave.)
from Clairville Rd. to South Park Ave. (approx. 2.4 miles)
County Road I (Oregon St.)
from 24th Ave. to Waukau Ave. (approx. 0.8 miles)
_________________
TOTAL approx. 6.8 miles
* The road segments/areas may expand or be revised in the future.
03/05/09 km nr216/osh mou
City of Oshkosh Stormwater Quality Management Plan
D-1
Oshkosh SWMP Final.docx
Appendix D: Airport Swale Testing Documentation
1. Wittman Airport Grass Swale Test Sites/Photos Map
2. Infiltration Testing Results
3. Photo Log
4. WDNR Correspondence
^_
^_
^_EE
EEEESite #1
Site #2
Site #3
6
1
5
4
3
2
Figure D-1Wittman Airport Grass Swale Test Sites/Photos MapCity of OshkoshStormwater Management Plan Update
Legend
Oshkosh Municipal Boundary
Swale Type
Type 1 (Wide)
Type 2 (Narrow)
Swale Drainage Area
^_Swale Test Site
EPicture Location & Direction
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure D-1 Airport Swale Test Sites.mxd5/4/20220 2,1001,050
Feet
±
Wittman Field Infiltration Testing: Summary
Project Number: 154820
Dynamic Rate
Location Test # Native Soil Inf. Rate* (in/hr)
Geometric Mean
(in/hr)
Geometric Mean
(in/hr)
Tarmac Area 1 4.62
West Side 2 4.88
East Side 3 3.75
*Value from best fit curve at 2 hours.
Static Rate
2.204.39
4/26/2022 Oshkosh Wittman Field Swale Infiltration Rate Test Resutls.xlsx]
Site:#1 (Tarmac / east-west runway swale)
Date:11/11/2021
Time:7:55 AM
Conditions:40 degrees, Partly Cloudy
Field Staff:Mike Wegner, Chuck Boehm
Amount / Date of Last Rain:0.16" (10 28-10/29)
Equipment Used:12" / 24" Metal Rings
Amount of Water Used:55 gallons
Water Level Time
Change in
Time
Water Level
Change (in)
Time Interval
Midpoint
(mm:ss)
Cumulative
Time to
Midpoint
(hh:mm:ss)
Infiltration
Rate
(in/hr)
5.50 0:00:00
5.00 0:00:30 00:30 0.50 00:15 0:00:15 60.00
4.00 0:02:26 01:56 1.00 00:58 0:01:28 31.03
3.00 0:04:40 02:14 1.00 01:07 0:03:33 26.87
6.00 0:05:45
5.00 0:08:10 02:25 1.00 01:12 0:06:57 24.83
4.00 0:10:30 02:20 1.00 01:10 0:09:20 25.71
3.50 0:19:40 09:10 0.50 04:35 0:15:05 3.27
3.00 0:24:35 04:55 0.50 02:27 0:22:08 6.10
6.00 0:25:40
5.50 0:28:06 02:26 0.50 01:13 0:26:53 12.33
5.00 0:31:05 02:59 0.50 01:29 0:29:35 10.06
4.50 0:34:05 03:00 0.50 01:30 0:32:35 10.00
4.00 0:37:50 03:45 0.50 01:53 0:35:58 8.00
6.00 0:39:25
5.50 0:44:15 04:50 0.50 02:25 0:41:50 6.21
5.00 0:47:40 03:25 0.50 01:42 0:45:58 8.78
4.50 0:51:55 04:15 0.50 02:08 0:49:48 7.06
4.00 0:56:00 04:05 0.50 02:03 0:53:58 7.35
6.00 0:56:55
5.50 1:02:10 05:15 0.50 02:38 0:59:33 5.71
5.00 1:06:55 04:45 0.50 02:23 1:04:33 6.32
4.50 1:11:45 04:50 0.50 02:25 1:09:20 6.21
4.00 1:16:40 04:55 0.50 02:27 1:14:12 6.10
6.00 1:17:20
5.50 1:23:40 06:20 0.50 03:10 1:20:30 4.74
5.00 1:29:25 05:45 0.50 02:53 1:26:33 5.22
4.50 1:34:50 05:25 0.50 02:43 1:32:08 5.54
4.00 1:40:30 05:40 0.50 02:50 1:37:40 5.29
6.00 1:41:35
5.50 1:48:25 06:50 0.50 03:25 1:45:00 4.39
5.00 1:55:15 06:50 0.50 03:25 1:51:50 4.39
4.75 1:58:05 02:50 0.25 01:25 1:56:40 5.29
4.50 2:00:45 02:40 0.25 01:20 1:59:25 5.62
shaded cells in table are formulas
4.62 in / hr
Double-Ring Infiltration Rate Test Field Sheet
Best Fit Rate @ 2 hours =
4/26/2022 Oshkosh Wittman Field Swale Infiltration Rate Test Resutls.xlsx
Site:#1 (Tarmac / east-west runway swale)
Date:11/11/2021
Time:7:55 AM
Conditions:40 degrees, Partly Cloudy
Field Staff:Mike Wegner, Chuck Boehm
Amount / Date of Last Rain:0.16" (10 28-10/29)
Equipment Used:12" / 24" Metal Rings
Amount of Water Used:55 gallons
Double-Ring Infiltration Rate Test Field Sheet
y = 1.3754x-0.488
R² = 0.9213
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
0:00 0:15 0:30 0:45 1:00 1:15 1:30 1:45 2:00 2:15 2:30Infiltration Rate (in/hr)Time (min)
Infiltration Rate Plot - #1 Wittman Field Tarmac Area
4/26/2022 Oshkosh Wittman Field Swale Infiltration Rate Test Resutls.xlsx
Site:#2 (West side swale - north-south taxi-way)
Date:11/11/2021
Time:10:30 AM
Conditions:45 degrees, Partly Cloudy
Field Staff:Mike Wegner, Chuck Boehm
Amount / Date of Last Rain:0.16" (10 28-10/29)
Equipment Used:12" / 24" Metal Rings
Amount of Water Used:80 gallons
Water Level Time
Change in
Time
Water Level
Change (in)
Time Interval
Midpoint
(mm:ss)
Cumulative
Time to
Midpoint
(hh:mm:ss)
Infiltration
Rate
(in/hr)
4.25 0:00:00
4.00 0:00:25 00:25 0.25 00:13 0:00:13 36.00
3.50 0:01:10 00:45 0.50 00:23 0:00:47 40.00
3.00 0:01:50 00:40 0.50 00:20 0:01:30 45.00
2.50 0:02:35 01:25 1.00 00:43 0:01:53 42.35
6.00 0:03:35
5.50 0:04:06 00:31 0.50 00:15 0:03:51 58.06
4.50 0:05:30 01:24 1.00 00:42 0:04:48 42.86
4.00 0:06:45 01:15 0.50 00:38 0:06:07 24.00
3.00 0:08:50 02:05 1.00 01:03 0:07:48 28.80
6.00 0:10:10
5.00 0:12:45 02:35 1.00 01:18 0:11:27 23.23
4.00 0:15:45 03:00 1.00 01:30 0:14:15 20.00
3.00 0:19:35 03:50 1.00 01:55 0:17:40 15.65
6.00 0:21:05
5.00 0:25:25 04:20 1.00 02:10 0:23:15 13.85
4.00 0:30:25 05:00 1.00 02:30 0:27:55 12.00
6.00 0:32:25
5.00 0:36:50 04:25 1.00 02:13 0:34:37 13.58
4.00 0:42:15 05:25 1.00 02:43 0:39:32 11.08
6.00 0:44:10
5.00 0:49:50 05:40 1.00 02:50 0:47:00 10.59
4.00 0:56:10 06:20 1.00 03:10 0:53:00 9.47
6.13 0:58:15
5.00 1:05:20 07:05 1.13 03:32 1:01:48 9.53
4.00 1:13:25 08:05 1.00 04:02 1:09:23 7.42
6.00 1:14:50
5.00 1:26:10 11:20 1.00 05:40 1:20:30 5.29
4.00 1:36:35 10:25 1.00 05:13 1:31:22 5.76
6.50 1:38:50
6.00 1:48:50 10:00 0.50 05:00 1:43:50 3.00
5.50 1:53:50 05:00 0.50 02:30 1:51:20 6.00
5.00 1:59:45 05:55 0.50 02:57 1:56:47 5.07
shaded cells in table are formulas
4.88 in / hr
Double-Ring Infiltration Rate Test Field Sheet
Best Fit Rate @ 2 hours =
4/26/2022 Oshkosh Wittman Field Swale Infiltration Rate Test Resutls.xlsx
Site:#2 (West side swale - north-south taxi-way)
Date:11/11/2021
Time:10:30 AM
Conditions:45 degrees, Partly Cloudy
Field Staff:Mike Wegner, Chuck Boehm
Amount / Date of Last Rain:0.16" (10 28-10/29)
Equipment Used:12" / 24" Metal Rings
Amount of Water Used:80 gallons
Double-Ring Infiltration Rate Test Field Sheet
y = 0.827x-0.714
R² = 0.9484
0.0
5.0
10.0
15.0
20.0
25.0
30.0
0:00 0:15 0:30 0:45 1:00 1:15 1:30 1:45 2:00 2:15 2:30Infiltration Rate (in/hr)Time (min)
Infiltration Rate Plot - #2 Wittman Field - West Side
4/26/2022 Oshkosh Wittman Field Swale Infiltration Rate Test Resutls.xlsx
Site:#2 (East side - Hughes St)
Date:11/11/2021
Time:1:45 PM
Conditions:50 degrees, Partly Cloudy
Field Staff:Mike Wegner, Chuck Boehm
Amount / Date of Last Rain:0.16" (10 28-10/29)
Equipment Used:12" / 24" Metal Rings
Amount of Water Used:60 gallons
Water Level Time
Change in
Time
Water Level
Change (in)
Time Interval
Midpoint
(mm:ss)
Cumulative
Time to
Midpoint
(hh:mm:ss)
Infiltration
Rate
(in/hr)
7.25 0:00:00
7.00 0:00:38 00:38 0.25 00:19 0:00:19 23.68
6.50 0:01:50 01:12 0.50 00:36 0:01:14 25.00
6.00 0:03:05 01:15 0.50 00:38 0:02:28 24.00
5.00 0:06:35 03:30 1.00 01:45 0:04:50 17.14
4.00 0:11:35 05:00 1.00 02:30 0:09:05 12.00
7.00 0:12:55
6.00 0:19:55 07:00 1.00 03:30 0:16:25 8.57
5.00 0:27:30 07:35 1.00 03:47 0:23:43 7.91
4.00 0:36:25 08:55 1.00 04:28 0:31:58 6.73
6.00 0:37:05
5.00 0:47:25 10:20 1.00 05:10 0:42:15 5.81
4.00 0:59:30 12:05 1.00 06:03 0:53:28 4.97
6.25 1:00:55
5.00 1:13:30 12:35 1.25 06:18 1:07:13 5.96
4.50 1:24:55 11:25 0.50 05:42 1:19:13 2.63
4.00 1:33:45 08:50 0.50 04:25 1:29:20 3.40
6.00 1:34:45
5.50 1:43:40 08:55 0.50 04:28 1:39:13 3.36
5.00 1:50:45 07:05 0.50 03:32 1:47:12 4.24
4.50 1:58:50 08:05 0.50 04:03 1:54:47 3.71
4.25 2:02:25 03:35 0.25 01:47 2:00:37 4.19
shaded cells in table are formulas
3.75 in / hr
Double-Ring Infiltration Rate Test Field Sheet
Best Fit Rate @ 2 hours =
4/26/2022 Oshkosh Wittman Field Swale Infiltration Rate Test Resutls.xlsx
Site:#2 (East side - Hughes St)
Date:11/11/2021
Time:1:45 PM
Conditions:50 degrees, Partly Cloudy
Field Staff:Mike Wegner, Chuck Boehm
Amount / Date of Last Rain:0.16" (10 28-10/29)
Equipment Used:12" / 24" Metal Rings
Amount of Water Used:60 gallons
Double-Ring Infiltration Rate Test Field Sheet
y = 1.2605x-0.439
R² = 0.8201
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
0:00 0:15 0:30 0:45 1:00 1:15 1:30 1:45 2:00 2:15 2:30Infiltration Rate (in/hr)Time (min)
Infiltration Rate Plot - #3 Hughes Street
4/26/2022 Oshkosh Wittman Field Swale Infiltration Rate Test Resutls.xlsx
Photo Log
Wittman Field Swale Infiltration Testing
City of Oshkosh, WI
Field Testing Equipment
Field Testing Equipment
Photo Log
Wittman Field Swale Infiltration Testing
City of Oshkosh, WI
Test Site #1 Equipment Set-up
Test Site #1 Wide Swale (Looking East)
Photo Log
Wittman Field Swale Infiltration Testing
City of Oshkosh, WI
Test Site #1 Wide Swale (Looking West)
Test Site #2 Wide Swale (Looking South)
Photo Log
Wittman Field Swale Infiltration Testing
City of Oshkosh, WI
Test Site #2 Wide Swale (Looking North)
Test Site #3 – Narrow Swale (Looking northeast)
Photo Log
Wittman Field Swale Infiltration Testing
City of Oshkosh, WI
Test Site #3 Narrow Swale (Looking Southwest)
Photo Location #1 (Looking West) Wide Swale
Photo Log
Wittman Field Swale Infiltration Testing
City of Oshkosh, WI
Photo Location #2 (Looking southeast) Narrow Swale
Photo Location #3 (Looking southwest) Wide Swale
Photo Log
Wittman Field Swale Infiltration Testing
City of Oshkosh, WI
Photo #4 (Looking north) Wide Swale
Photo #5 (Looking north) Wide Swale
Photo Log
Wittman Field Swale Infiltration Testing
City of Oshkosh, WI
Photo #6 (Looking west) Wide Swale
From: Minser, Amy J - DNR <Amy.Minser@wisconsin.gov>
Sent: Tuesday, November 2, 2021 3:36 PM
To: Chuck Boehm <CBoehm@BrwnCald.com>
Cc: Linskens, Christopher J - DNR <Christopher.Linskens@wisconsin.gov>
Subject: RE: Swale mark up
Chuck,
The locations look reasonable for the swale testing, but I have a bigger concern. The airport is county
property, and unless the City has a written agreement with the County that allows them to take credit
for the loading and treatment on county property, the City should not be including the airport in their
modeling. We discussed this during review of the last update and they ended up listing it out separately
in that report because there was not a signed agreement with the County. Is there an agreement now?
We are committed to service excellence.
Visit our survey at http://dnr.wi.gov/customersurvey to evaluate how I did.
Amy Minser
Phone: 608-266-4359
Cell: 920-360-0913
amy.minser@wisconsin.gov
From: Chuck Boehm <CBoehm@BrwnCald.com>
Sent: Tuesday, November 2, 2021 3:18 PM
To: Minser, Amy J - DNR <Amy.Minser@wisconsin.gov>
Subject: FW: Swale mark up
Importance: High
CAUTION: This email originated from outside the organization.
Do not click links or open attachments unless you recognize the sender and know the content is
safe.
Greetings Amy,
I just wanted to let you know that we are planning to do some grassed swale infiltration testing at
Wittman Regional Airport as part of the City of Oshkosh Citywide Stormwater Quality (TMDL) Plan
update, which is partially WDNR grant funded.
Our grant and project scope identified up to 3 infiltration test locations which we have in the attached
figure and are discussed in the email communication with airport staff below. We are trying to stay out
of the more sensitive airport access and safety locations (see jpg file) to the extent possible.
We typically like to keep WDNR staff involved as we go through this process so there are no surprises.
Please let me know if you have any feedback or comments on the identified test locations, or feel we
should be in discussion with anyone else at the WDNR as we go through this process, or if WDNR does
not feel the need to review or comment on our plan/efforts.
Thanks for your feedback!
Chuck Boehm, PE
Director, Client Services
Brown and Caldwell | Milwaukee
T 414.203.2899 | C 262.488.3350 | CBoehm@brwncald.com
Get water industry news delivered to your desktop, free, from BCWaterNews.com Sign up now!
Professional Registration in Specific States
From: Chuck Boehm
Sent: Tuesday, November 2, 2021 2:45 PM
To: Hallock, Cameron <CHallock@co.winnebago.wi.us>; jschell@co.winnebago.wi.us; Gierach, Justin
<JGierach@ci.oshkosh.wi.us>
Cc: Gabrilska, Dan <dgabrilska@ci.oshkosh.wi.us>; Mike Wegner <mwegner@BrwnCald.com>; Doug
Joachim <djoachim@BrwnCald.com>
Subject: RE: Swale mark up
Importance: High
Greetings Cameron and Jim,
Thanks again for your time yesterday and for marking up the swale figure.
We looked it over and identified the three locations (see attached figure) that we feel best characterize
the different types of swales and are dispersed geographically well, while trying to stay out of the more
restrictive access areas of the airport. We currently think that doing them in numeric order probably
makes the most sense.
Details and questions are as follows:
Site #1 is in one of the yellow areas you identified. The swale appears typical of the main east-west
runway. Would it be acceptable to be parked on the southern area of the pavement adjacent to the
grassed area? We expect at least one BC vehicle (full size pickup truck) and probably a City water supply
vehicle (still coordinating that with City staff).
Site #2 is in a green area. This is one of the flatter swales and characteristic of the north-south runways
and probably much of the flatter grassed areas of the airport. We are thinking we could park just to the
north of Waukau Avenue (extended).
Site #3 is also in a green area. It is actually outside of the fence line just to the southwest of where
Aviation Court and Hughes Street intersect and representative of typical swales/ditches in the
area. There appears to be a gravel shoulder on the south side along Aviation Court at the entry to the
airport that we should be able to park out of the way.
Based on a current look at weather, staff availability and other factors, we would like to target our
infiltration testing for Wednesday November 10th, arriving at the airport and conducting testing at Site
#1 as early in the morning as we can get all folks mobilized (between 7 and 8 am ideally). We anticipate
approximately 2.5 hours per location, so we should be able to be off airport property well within the
normal 7am-3pm day.
We will be tamping our metal double-ring infiltrometer device (concentric rings of 12-inches and 24-
inches in diameter) into the ground 3-4 inches or so typically, I don’t think we ever needed to go more
than 6-inches to get a good seal with the surrounding ground. Are there any concerns with shallow
utilities in the areas we have identified on airport property?
One other question - would it be possible for us to have a quick escorted visit to various areas so we
could take photos to document the general condition of the swales for our report and modeling efforts?
We still need to coordinate with City for water and will be checking in with WDNR, but this is our current
thoughts on timing. We would appreciate your feedback on the above and any additional questions on
your end.
Justin – I will be reaching out to the WDNR with this figure and plan of potential locations. They
typically do not have any concerns, but we like to keep them in the loop.
We have 5 containers that each hold 5 gallons of water. I will follow-up with you on utilities along
Hughes Street and also water supply needs. We have used up to 200 gallons in test areas with high
infiltration rates in the City.
Mike/Doug – please weigh in if I forgot any details.
Thanks!
Chuck Boehm, PE
Director, Client Services
Brown and Caldwell | Milwaukee
T 414.203.2899 | C 262.488.3350 | CBoehm@brwncald.com
Get water industry news delivered to your desktop, free, from BCWaterNews.com Sign up now!
Professional Registration in Specific States
From: Hallock, Cameron <CHallock@co.winnebago.wi.us>
Sent: Monday, November 1, 2021 3:21 PM
To: Chuck Boehm <CBoehm@BrwnCald.com>
Cc: Schell, Jim <JSchell@co.winnebago.wi.us>
Subject: Swale mark up
Chuck,
Attached is the swale map with my mark ups. We can provide access to any area on the airport for swale
testing, however, the yellow and red areas require pre-planning and coordination with the Air Traffic
Control Tower.
Areas circled in:
Green – Easy access, no pre-coordination with Control Tower (requires escort to/from location with
Airport Staff)
Yellow – Requires pre-coordination with Air Traffic Control. Need at least 24 hours to plan. Minimum
impact to aircraft operations.
Red – Potentially requires a runway closure. Impacts aircraft operations. Need at least 24 hours to plan.
Thanks,
Cameron Hallock
Deputy Director, Wittman Regional Airport
920-236-4935 (Office)
920-420-8271 (Cell)
Follow us on Facebook and Instagram!
City of Oshkosh Stormwater Quality Management Plan
E-1
Oshkosh SWMP Final.docx
Appendix E: “With Controls” Analysis Additional
Information
1. Regional SMP Details
2. Non-Regional SMP Details
3. Pollutant Loadings by Watershed
Reachshed Regional SMP Name SMP ID Owner
Treatment
Area (ac)Type of SMP
No Controls
TSS Load
(tons)
With Controls
TSS Load
(tons)
TSS Load
Reduction
(tons)
TSS Load
Reduction
(%)
No Controls
TP Load
(lbs)
With Controls
TP Load
(lbs)
TP Load
Reduction
(lbs)
TP Load
Reduction
(%)
Armory Reg-1 City 416.6 Wet Pond 86.5 6.3 80.1 93% 356.6 74.9 281.7 79%
City Hall Reg-2 City 106.9
Underground
Detention 15.0 7.2 7.9 52% 99.6 61.5 38.0 38%
South Park Reg-3 City 660.1 Wet Pond 111.4 45.4 66.0 59% 572.0 247.6 324.4 57%
E Nevada Ave Reg-4 City 94.7 Lift Station 10.6 7.7 2.9 27% 77.1 63.6 13.4 17%
Fair Acres/Murdock Reg-5 City 93.0 Wet Pond 16.0 4.7 11.3 71% 86.4 38.8 47.6 55%
Fernau Watershed - North
Main Street Area Reg-6 City 151.1 Wet Pond 30.1 3.9 26.3 87% 129.2 48.1 81.2 63%
Libbey-Nicolet Reg-7 City 341.4 Wet Pond 55.7 15.6 40.0 72%289.4 135.8 153.6 53%
Melvin Ave Reg-8 City 110.8 Lift Station 13.3 9.1 4.1 31% 93.9 73.8 20.0 21%
North High School Area Reg-9 City 77.1 Wet Pond 8.9 1.2 7.6 86% 62.5 20.8 41.7 67%
9th & Washburn Reg-10 City 293.6 Wet Pond 32.4 5.4 26.9 83%217.0 84.4 132.6 61%
Oakwood Road Reg-11 City 56.9 Wet Pond 13.2 1.0 12.2 92% 47.7 17.1 30.6 64%
Westhaven Club House Reg-12 City 72.6 Wet Pond 7.2 0.3 6.9 96% 55.0 14.8 40.1 73%
Lake Winnebago
Sawyer Creek
Table E-1
Regional SMP Details
Stormwater Management Plan Update
City of Oshkosh, WI
Upper Fox/Wolf TMDL
Fox River - Lake Butte
des Morts to Lake
Winnebago
APPENDIX Regional SMP Details.xlsx 9/21/2022
Reachshed Non-Regional
SMP Name SMP ID Public/
Private
Treatment
Area (ac)Type of SMP
No Controls
TSS Load
(tons)
With Controls
TSS Load
(tons)
TSS Load
Reduction
(tons)
TSS Load
Reduction
(%)
No Controls
TP Load
(lbs)
No Controls
TSS Load
(lbs)
TP Load
Reduction
(lbs)
TP Load
Reduction
(%)
O&M
Agreement?
400 E. Main
Parking Lot 2 City 1.6 Biofilter 0.31 0.18 0.13 41% 1.57 1.02 0.55 35% N/A
460 Marion 3 City 0.6
Catch Basin /
Swale 0.15 0.12 0.04 24% 0.64 0.53 0.11 18% N/A
Bridgeview
Holdings 8 Private 0.9 Biofilter 0.17 0.14 0.03 16% 0.86 0.77 0.09 11% InProgress
Ceape Ave Parking
Lot 10 City 1.4
Permeable
Pavement 0.27 0.12 0.15 57% 1.37 0.85 0.52 38% N/A
City Hall Bio 12 City 2.5 Biofilter 0.49 0.17 0.32 65% 2.50 1.17 1.33 53% N/A
Floor Quest 19 Private 2.6 Wet Pond/Biofilter 0.66 0.17 0.49 74% 2.79 1.40 1.39 50% Yes
Lourdes School 30 Private 17.6
Biofilter/Catch
Basin 3.38 2.98 0.40 12% 17.84 16.40 1.43 8% InProgress
Merge
Development - Site
J
32 Private 2.6 Underground 0.60 0.55 0.06 9% 1.98 1.85 0.13 6% InProgress
Mineshaft 33 Private 26.4
Catch Basin /
Filter 5.26 4.32 0.95 18% 22.40 19.68 2.72 12% InProgress
Osborn Apartments 38 Private 9.9 Wet Pond 0.23 0.02 0.21 93% 1.69 0.63 1.06 63% InProgress
Otter Ave 41 City 0.8 Biofilter 0.15 0.09 0.07 44% 0.77 0.57 0.20 26% N/A
Otter Avenue
Parkng Lot 42 City 0.5
Permeable
Pavement 0.10 0.04 0.06 57% 0.53 0.33 0.21 39% N/A
Payne Art Center 43 Private 4.2
Biofilter/Filter/
PermPave 0.82 0.72 0.10 12% 3.88 3.56 0.32 8% Yes
Public Works Field
Operations 46 City 14.8
Biofilters/
Underground/
Catch Basins
3.32 1.63 1.70 51% 11.81 7.75 4.07 34% N/A
Salvation Army 49 Private 0.6 Biofilter 0.11 0.05 0.06 55% 0.55 0.34 0.20 37% InProgress
Senior Center 51 City 1.0
Permeable
Pavement 0.19 0.11 0.08 44% 0.90 0.63 0.27 30% N/A
The Rivers - Phase II 60 Private 1.2 Biofilter 0.27 0.16 0.11 42% 0.90 0.64 0.25 28% Yes
The Rivers Biofilter 61 Private 1.8 Biofilter 0.24 0.15 0.09 38% 1.60 1.09 0.50 32% Yes
Casey's General
Store - Oshkosh Ave 9 Private 1.4 Underground 0.11 0.02 0.08 79% 0.92 0.43 0.49 53%Yes
Choice Bank 11 Private 1.8 Underground 0.46 0.17 0.29 63% 1.94 1.12 0.83 43% Yes
Table E-2
Non-Regional SMP Details
Stormwater Management Plan Update
City of Oshkosh, WI
Upper Fox/Wolf TMDL
Fox River - Lake
Butte des Morts
to Lake
Winnebago
APPENDIX NonRegional SMP Details.xlsx 9/21/2022
Reachshed Non-Regional
SMP Name SMP ID Public/
Private
Treatment
Area (ac)Type of SMP
No Controls
TSS Load
(tons)
With Controls
TSS Load
(tons)
TSS Load
Reduction
(tons)
TSS Load
Reduction
(%)
No Controls
TP Load
(lbs)
No Controls
TSS Load
(lbs)
TP Load
Reduction
(lbs)
TP Load
Reduction
(%)
O&M
Agreement?
Table E-2
Non-Regional SMP Details
Stormwater Management Plan Update
City of Oshkosh, WI
Upper Fox/Wolf TMDL
Fire Station 19 18 City 1.9 Filter Strip 0.37 0.28 0.09 25%1.75 1.45 0.29 17% N/A
Fox Community
Credit Union 20 Private 1.3 Wet Pond 0.34 0.15 0.19 56% 1.45 0.80 0.65 45% InProgress
Lakeshore
Developments - 27 Private 2.6 Biofilter/Filter 0.20 0.05 0.15 75% 1.74 0.86 0.88 50% InProgress
Lakeshore
Developments -
Hotel
28 Private 6.5 Biofilter/Filter 1.24 0.41 0.82 67% 6.03 3.32 2.71 45% InProgress
Lakeshore Park
Building 29 City 3.7 Biofilter 0.23 0.05 0.18 78% 2.07 0.99 1.09 52% N/A
Oshkosh Defense
Storage Yard 40 Private 4.5 Wet Pond 1.05 0.81 0.24 23% 3.42 2.89 0.53 15% Yes
Pickart Estates 45 Private 11.3 Wet Pond 0.98 0.26 0.71 73%7.70 3.90 3.79 49% Yes
Riverside Cemetery 48 City 98.4
Grass
Swales/Filter
Strips
6.16 4.50 1.66 27% 60.03 49.13 10.90 18% N/A
Sunnyview Landfill
Admin Office
Addition
55 County 208.9 Swale 5.11 2.93 2.19 43% 62.35 44.35 18.00 29%Yes
TID 34 63 City 19.0 Wet Pond 1.18 0.21 0.97 82% 10.65 4.75 5.91 55% N/A
TID 35 64 City 3.2
Prairie Treatment
Systems (2)0.21 0.04 0.17 81% 1.89 0.86 1.03 54% N/A
Washburn St 67 City 73.8 Wet Pond 16.18 5.83 10.36 64% 70.99 34.78 36.20 51% N/A
2750 Vinland LLC 1 Private 36.3 Wet Pond 9.37 3.25 6.12 65% 32.91 18.40 14.52 44% InProgress
Anchorage Realty 4 Private 3.3
Swale /
Underground 0.85 0.51 0.34 40% 2.99 2.19 0.80 27% Yes
Aviation Business
Park 5 City 70.7 Wet Pond 1.73 0.32 1.41 82% 21.10 9.46 11.64 55% N/A
Bergstrom
Automotive Factiliy 6 Private 0.0 Wet Pond 0.00 0.00 0.00 42% 0.00 0.00 0.00 33% InProgress
Big Rig Chrome
Shop 7 Private 4.3 Wet Pond 1.10 0.18 0.91 83% 4.62 2.02 2.60 56% Yes
EAA Bus Stop Start
Post and Homebuilt 14 Private 48.4 Biofilter 2.18 2.06 0.12 5% 20.11 19.38 0.73 4% InProgress
Evco Plastics 15 Private 9.0 Wet Pond 2.32 1.73 0.59 26% 8.15 6.74 1.41 17% InProgress
Lake Butte des
Morts
APPENDIX NonRegional SMP Details.xlsx 9/21/2022
Reachshed Non-Regional
SMP Name SMP ID Public/
Private
Treatment
Area (ac)Type of SMP
No Controls
TSS Load
(tons)
With Controls
TSS Load
(tons)
TSS Load
Reduction
(tons)
TSS Load
Reduction
(%)
No Controls
TP Load
(lbs)
No Controls
TSS Load
(lbs)
TP Load
Reduction
(lbs)
TP Load
Reduction
(%)
O&M
Agreement?
Table E-2
Non-Regional SMP Details
Stormwater Management Plan Update
City of Oshkosh, WI
Upper Fox/Wolf TMDL
Generac Power
Systems 21 Private 21.7 Wet Pond 5.60 2.25 3.35 60% 19.67 11.73 7.94 40% InProgress
Grove Street
Condos 22 Private 1.1 Swale 0.15 0.12 0.03 21% 1.01 0.87 0.14 14% Yes
Henke Landscaping 23 Private 3.7 Wet Pond 0.95 0.34 0.62 65% 4.01 2.26 1.75 44% Yes
Hydrite 25 Private 19.0 Biofilter 4.91 3.75 1.16 24% 17.24 14.48 2.76 16% InProgress
Jackson Street
Storage 26 Private 4.1 Biofilter 0.43 0.09 0.34 80% 3.17 1.46 1.71 54%InProgress
Matthews Senior
Living 31 Private 4.5 Wet Pond 1.16 0.41 0.74 64% 4.88 2.55 2.33 48% InProgress
Muza Sheet Metal -
Main St 34 Private 2.3 Wet Pond 0.59 0.39 0.20 33% 2.07 1.61 0.46 22% InProgress
NW Ind. Park 37 City 33.5 Wet Pond 5.50 0.11 5.39 98% 25.43 14.24 11.19 44% N/A
Oshkosh Defense
North Plant Parking
Lot
39 Private 14.3 Filter 3.28 3.00 0.28 8% 10.73 10.12 0.61 6% InProgress
Ripple Avenue
Estates 47 Private 14.8 Wet Pond 2.01 0.36 1.65 82% 13.22 5.90 7.32 55% Yes
Soda Creek Estates 52 Private 17.3 Wet Pond 2.36 0.35 2.00 85% 15.51 6.61 8.90 57% Yes
St. Mary's Cabrini
Adaptive Reuse 53 Private 1.4 Underground 0.27 0.22 0.05 18% 1.28 1.13 0.15 12% InProgress
Sunnyview Expo 54 County 21.3 Wet Pond 1.32 0.77 0.55 42% 11.98 8.61 3.37 28% InProgress
Valley Christian
School 65 Private 14.5 Wet Pond 2.48 1.11 1.37 55% 14.45 8.71 5.74 40% InProgress
Waite Rug Place 66 Private 5.2 Biofilter 1.34 1.05 0.29 22%4.71 4.02 0.69 15% Yes
Wittman Airport -
Moehn Hangar 68 County 0.9 Filter Strip 0.04 0.04 0.00 6% 0.39 0.37 0.02 6%InProgress
Wittman Airport -
Sonex Aircraft
Hangar
69 County 2.8 Swale 0.13 0.11 0.01 10% 1.17 1.09 0.08 6% InProgress
Woodstock Village 70 Private 4.8 Wet Pond 0.91 0.17 0.74 81%4.13 1.60 2.53 61% InProgress
YMCA - Downtown 71 Private 4.3
Permeable
Pavement 0.83 0.76 0.07 9% 4.22 3.97 0.25 6% Yes
Lake Winnebago
APPENDIX NonRegional SMP Details.xlsx 9/21/2022
Reachshed Non-Regional
SMP Name SMP ID Public/
Private
Treatment
Area (ac)Type of SMP
No Controls
TSS Load
(tons)
With Controls
TSS Load
(tons)
TSS Load
Reduction
(tons)
TSS Load
Reduction
(%)
No Controls
TP Load
(lbs)
No Controls
TSS Load
(lbs)
TP Load
Reduction
(lbs)
TP Load
Reduction
(%)
O&M
Agreement?
Table E-2
Non-Regional SMP Details
Stormwater Management Plan Update
City of Oshkosh, WI
Upper Fox/Wolf TMDL
Cumberland
Apartments 13 Private 5.2 Biofilter 0.70 0.56 0.14 20% 4.61 3.98 0.63 14%Yes
Evergreen Manor
Inc.16 Private 3.0 Wet Pond 0.41 0.08 0.33 80% 2.68 1.07 1.61 60% Yes
Evergreen
Retirement - Linden
Oaks
72 Private 10.8 Wet Pond 1.45 0.49 0.96 66% 10.32 5.11 5.20 50% InProgress
Fire Station #16 17 City 1.3
Permeable
Pavement 0.25 0.08 0.17 69% 1.18 0.63 0.55 46% N/A
Heritage Senior
Living 24 Private 14.5 Wet Pond 1.98 0.84 1.13 57% 13.00 5.80 7.21 55% InProgress
Muza Sheet Metal -
Oakwood Rd 35 Private 7.2 Wet Pond 1.87 0.85 1.02 55% 6.57 3.81 2.76 42% Yes
North Koeller Street
Office Building 36 Private 1.1 Biofilter 0.28 0.10 0.18 63% 1.18 0.68 0.50 42%Yes
Pepsi Co. 44 Private 24.4 Wet Pond 6.30 5.90 0.41 6% 22.14 21.17 0.96 4% InProgress
SCS Oshkosh 50 Private 1.2 Wet Pond 0.17 0.03 0.14 81% 1.10 0.48 0.62 56% InProgress
Sunrise Estates 56 Private 12.4 Wet Pond 0.91 0.17 0.74 81%7.90 3.89 4.02 51% Yes
SWIP Pond A 57 City 20.6 Wet Pond 0.50 0.10 0.40 80% 6.15 2.83 3.32 54% N/A
SWIP Pond B 58 City 10.2 Wet Pond 0.25 0.05 0.20 80% 3.06 1.41 1.65 54% N/A
SWIP Pond C 59 City 3.0 Wet Pond 0.07 0.01 0.06 80% 0.90 0.41 0.49 54% N/A
The Wit 62 Private 18.6 Wet Pond 0.45 0.07 0.39 86% 5.54 2.34 3.20 58% InProgress
Sawyer Creek
APPENDIX NonRegional SMP Details.xlsx 9/21/2022
Reachshed WATERSHED Area
No Controls
TSS Load
(tons)
With Controls
TSS Load
(tons)
No Controls TP
Load
(lbs)
With Controls
TP Load
(lbs)
10th Ave 35.1 6.0 5.3 27.0 25.2
3rd Ave 49.0 9.7 7.0 43.1 35.6
4th Ave 11.4 2.7 2.7 10.5 10.4
6th Ave 8.8 1.9 1.7 8.4 7.9
Blackhawk St 46.5 8.0 7.0 45.9 42.7
Campbell Creek 1182.4 197.7 99.3 1012.3 660.3
Court St 23.7 4.6 3.2 23.3 18.4
Dawes St 44.4 8.7 6.8 42.6 36.3
Division St 211.0 36.0 22.9 200.0 145.3
Minnesota St 12.9 3.3 3.0 11.7 11.2
Nebraska St 56.5 9.3 7.8 53.0 47.4
North Main St 45.8 8.9 6.2 45.1 35.8
North Sawyer St 141.0 20.0 18.2 123.4 116.1
Ohio St 74.1 10.9 8.8 66.6 57.7
Osceola St 139.2 20.1 15.5 127.9 109.4
Rainbow Park 41.6 4.3 4.0 30.7 29.1
River Mill Rd 29.0 3.2 2.6 23.5 20.7
South Main St 19.1 3.6 3.2 16.7 15.8
Stringham Creek 812.5 132.7 63.3 704.7 366.4
Vine Ave 57.7 9.3 7.7 49.9 43.8
Warren St 12.9 2.3 2.1 12.6 11.9
West Murdock Ave 289.6 35.6 29.7 247.9 222.6
Fox River - Lake Butte
des Morts to Lake
Winnebago
Table E-3
Pollutant Loadings by Watershed
Stormwater Management Plan Update
City of Oshkosh, WI
APPENDIX Loads by City Watershed 9/21/2022
Reachshed WATERSHED Area
No Controls
TSS Load
(tons)
With Controls
TSS Load
(tons)
No Controls TP
Load
(lbs)
With Controls
TP Load
(lbs)
Table E-3
Pollutant Loadings by Watershed
Stormwater Management Plan Update
City of Oshkosh, WI
West New York Ave 72.5 9.6 7.3 61.0 51.0
Woodland Ave 50.9 9.5 8.5 45.3 41.8
21/41 Interchange 36.7 6.0 5.0 30.9 27.6
Edgewood Lane 119.2 10.9 8.5 77.9 63.9
Green Valley Rd 1014.4 116.9 94.6 644.2 530.2
Honey Creek 14.3 0.9 0.5 7.4 5.3
Kewaunee St 6.5 1.1 0.6 6.0 4.0
Lake Shore Golf Course 123.4 9.2 6.8 75.6 63.3
Lakeview Cemetary 46.2 2.9 2.3 28.4 24.1
Omro Rd 143.4 30.1 16.9 139.9 93.8
Packer Ave 127.2 13.1 11.5 92.0 84.2
Riverside Cemetary 17.0 1.5 1.2 11.5 9.6
Shangri La Point Rd 1.9 0.1 0.0 0.8 0.4
Stillman Dr 155.1 26.0 22.4 105.9 96.2
West Snell Rd 250.6 16.8 9.3 115.6 78.1
Lake Butte des Morts
APPENDIX Loads by City Watershed 9/21/2022
Reachshed WATERSHED Area
No Controls
TSS Load
(tons)
With Controls
TSS Load
(tons)
No Controls TP
Load
(lbs)
With Controls
TP Load
(lbs)
Table E-3
Pollutant Loadings by Watershed
Stormwater Management Plan Update
City of Oshkosh, WI
Wilson Ave 63.9 6.1 5.4 47.8 44.4
14th Ave 128.9 15.3 12.5 107.3 95.4
15th Ave 14.7 2.1 1.6 12.2 10.2
16th Ave 34.3 5.1 4.1 30.2 26.9
17th Ave 140.4 16.5 14.1 116.7 106.5
18th Ave 20.5 2.0 1.7 15.3 14.1
19th Ave 107.4 12.2 10.3 87.6 78.8
24th Ave 102.7 15.4 12.8 84.4 75.1
Alpine Ct 9.2 1.0 0.8 7.4 6.6
Anchorage Ct 476.0 77.3 53.8 421.9 331.3
Asylum Point 89.5 12.5 12.5 64.6 64.6
Babbitz Ave 4.8 0.5 0.4 4.0 3.4
Baldwin Ave 124.2 15.4 11.3 105.9 87.8
Bavarian Ct 8.5 0.9 0.8 6.6 6.2
Bay St 37.6 5.7 4.5 34.4 29.0
Bowen St 79.5 10.2 8.1 69.7 60.7
Broad St 34.8 6.3 5.2 33.6 29.8
Ceape Ave 32.8 3.9 3.1 28.0 24.4
Chestnut St 44.8 3.8 3.3 31.1 28.6
Cliffview Ct Island 9.8 1.0 0.9 7.6 7.3
Congress Ave 17.9 2.6 2.1 14.8 13.0
Doemel St 31.8 3.3 2.7 25.2 22.5
East Murdock Ave 26.7 2.7 2.2 20.9 18.9
East New York Ave 51.7 5.9 4.9 43.3 39.1
APPENDIX Loads by City Watershed 9/21/2022
Reachshed WATERSHED Area
No Controls
TSS Load
(tons)
With Controls
TSS Load
(tons)
No Controls TP
Load
(lbs)
With Controls
TP Load
(lbs)
Table E-3
Pollutant Loadings by Watershed
Stormwater Management Plan Update
City of Oshkosh, WI
East Snell Rd 537.3 48.1 37.6 352.8 306.0
Eveline St 20.0 2.0 1.7 15.4 13.6
Fairview St 16.3 1.7 1.4 12.7 11.9
Fernau Ave 567.2 111.5 64.1 482.2 319.3
Frankfort St 21.7 2.1 1.8 16.5 14.5
Gallups/Merritts Creek 669.9 98.1 71.2 458.0 344.1
Glatz Creek 1521.7 134.4 90.9 837.7 502.3
Greenwood Ct 4.6 0.6 0.5 3.9 3.6
Hickory Lane 39.9 3.3 2.4 27.1 20.4
Irving Ave 88.3 9.7 7.4 71.0 60.5
Johnson Ave 281.8 29.0 18.7 176.5 124.5
Lake St 8.2 0.8 0.7 6.4 5.6
Lawndale St 8.9 0.8 0.7 6.4 5.7
Leeward Ct 17.4 3.3 2.9 14.9 13.8
Legion Place 1.3 0.1 0.1 1.0 1.0
Libbey Ave 432.2 62.3 27.5 363.4 209.3
Lincoln Ave 18.9 2.2 1.9 16.3 14.9
Linde St 14.4 0.9 0.8 8.1 7.7
Melvin Ave 110.8 13.3 9.1 93.9 73.8
Menominee Park Central 12.6 0.8 0.7 7.1 6.8
Lake Winnebago
APPENDIX Loads by City Watershed 9/21/2022
Reachshed WATERSHED Area
No Controls
TSS Load
(tons)
With Controls
TSS Load
(tons)
No Controls TP
Load
(lbs)
With Controls
TP Load
(lbs)
Table E-3
Pollutant Loadings by Watershed
Stormwater Management Plan Update
City of Oshkosh, WI
Menominee Park South 13.8 0.9 0.8 7.8 7.6
Merritt Ave 63.6 9.1 7.4 52.8 46.2
Mill St 10.1 1.6 1.2 9.5 7.7
Nevada Ave 94.7 10.6 7.7 77.1 63.6
Nicolet Ave 204.9 40.7 24.6 170.2 121.7
Oak St 21.7 2.6 2.3 17.7 16.5
Otter Ave 9.3 1.0 0.8 7.7 6.4
Parkway 121.7 15.1 11.2 104.3 87.0
Pioneer Dr 25.7 4.1 3.6 19.9 19.0
Pioneer Island 10.5 2.7 2.7 11.2 11.2
Rahr Ave 5.9 0.6 0.5 4.4 4.0
Sherman Rd North 0.2 0.0 0.0 0.2 0.1
Sherman Rd South 147.6 25.5 13.3 125.4 70.7
Shorewood Dr Penninsula 24.8 2.5 2.3 19.2 18.4
Siewert Trail 15.5 1.6 1.4 11.4 10.7
Starboard Ct 17.0 2.3 1.9 14.5 12.9
Sunnyview Rd 125.8 15.1 13.2 91.1 79.0
Washington Ave 27.7 3.3 2.7 21.7 19.3
Waugoo Ave 28.0 3.2 2.7 23.9 21.8
Welle Dr 3.2 0.4 0.3 2.9 2.3
Weyhurst Creek 27.4 2.0 1.1 15.4 11.3
APPENDIX Loads by City Watershed 9/21/2022
Reachshed WATERSHED Area
No Controls
TSS Load
(tons)
With Controls
TSS Load
(tons)
No Controls TP
Load
(lbs)
With Controls
TP Load
(lbs)
Table E-3
Pollutant Loadings by Watershed
Stormwater Management Plan Update
City of Oshkosh, WI
White Swan Dr 11.5 1.1 1.0 8.9 8.3
Windward Ct Island 6.1 0.6 0.6 4.8 4.5
Winnebago Ave 25.0 3.0 2.6 21.1 19.2
Neenah Slough
(Lower Fox River
TMDL)
Neenah Slough 35.1 2.2 2.2 19.7 19.7
Dove St 1.6 0.3 0.3 1.6 1.4
Red Arrow Park 36.5 5.4 4.9 33.1 31.6
Sawyer Creek 2642.9 343.1 247.1 2043.7 1625.4
West Algoma Park 3.4 0.4 0.4 3.0 2.8
Sawyer Creek
APPENDIX Loads by City Watershed 9/21/2022
City of Oshkosh Stormwater Quality Management Plan
F-1
Oshkosh SWMP Final.docx
Appendix F: Non-Regional SMPs with O&M
Agreements Not Found Additional Information
Reachshed Non-Regional
SMP Name SMP ID Public/
Private
Treatment
Area (ac)Type of SMP
No
Controls
TSS Load
(tons)
Ex.Cond.
TSS Load
(tons)
w/ Non-
Regional
SMP TSS
Load (tons)
Incremental
TSS Load
Reduction
(tons)
Incremental
TSS Load
Reduction
(%)
No
Controls
TP Load
(lbs)
Ex.Cond.
TP Load
(lbs)
w/ Non-
Regional
SMP TP
Load (lbs)
Incremental
TP Load
Reduction
(lbs)
Incremental
TP Load
Reduction
(%)
Regional SMP
Downstream?
1200 Koeller St Add-NR-1 Private 6.3 Wet Pond 1.21 0.10 0.09 0.00 0% 5.14 1.11 1.09 0.01 0% Armory Area
Alumni Center Add-NR-67
UW-
Oshkosh 1.5 Biofilter 0.39 0.33 0.09 0.24 60% 1.39 1.22 0.66 0.56 40% No
Annex 71 LLC Add-NR-9 Private 5.0 Wet Pond 1.28 1.01 0.56 0.46 35% 4.51 3.89 2.69 1.20 27% No
Associated Bank Add-NR-11 Private 1.3 Biofilter 0.33 0.13 0.13 0.00 0% 1.38 0.60 0.60 0.00 0% South Park
Block Iron &
Supply Co.Add-NR-15 Private 2.9 Filter 0.73 0.64 0.53 0.11 15% 3.08 2.81 2.51 0.30 10% No
Century Oaks -
Phase III Add-NR-18 Private 1.8 Biofilter 0.14 0.11 0.08 0.03 24% 1.19 1.07 0.84 0.23 19% No
Culver's Add-NR-21 Private 0.8 Biofilter 0.21 0.02 0.02 0.00 0% 0.90 0.19 0.19 0.00 0% Armory Area
Curwood Inc Add-NR-22 Private 106.9
Wet
Pond/Swale 27.62 7.94 7.94 0.00 0% 97.00 34.23 34.23 0.00 0%
Armory & South
Park
CVS Pharmacy Add-NR-23 Private 1.8 Underground 0.25 0.19 0.14 0.06 22% 1.63 1.38 1.14 0.24 15% No
Deerfield Village Add-NR-24 Private 4.3 Wet Pond 1.10 1.06 0.29 0.76 69% 3.88 3.72 1.74 1.98 51% No
Fletcher Hall Add-NR-33
UW-
Oshkosh 5.1 Biofilter/Swal
e 0.86 0.70 0.62 0.08 9% 5.02 4.43 4.04 0.39 8% No
Fox World Travel Add-NR-36 Private 3.1
Swale / Catch
Basin 0.78 0.32 0.32 0.00 0% 3.31 1.43 1.43 0.00 0% South Park
Market Fair
Outbuilding Add-NR-87 Private 10.2 Catch Basin 1.96 0.14 0.14 0.00 0% 8.35 1.75 1.75 0.00 0% Armory Area
Morton Pharmacy Add-NR-45 Private 4.2 Biofilter 1.07 0.78 0.66 0.12 11% 4.52 3.61 3.07 0.54 12% No
Multi Bldg. LLC Add-NR-46 Private 5.1 Wet Pond 1.31 0.10 0.10 0.00 0% 4.60 0.97 0.97 0.00 0% Armory Area
Potbelly Sandwich
Shop Add-NR-57 Private 0.6 Biofilter 0.11 0.11 0.08 0.02 19% 0.48 0.46 0.40 0.06 13% No
Taco Johns Add-NR-64 Private 1.5 Biofilter 0.39 0.16 0.11 0.05 13% 1.65 0.71 0.85 0.00 0% South Park
Target Complex Add-NR-65 Private 19.3 Wet Pond 3.99 1.63 1.16 0.47 12% 16.96 7.34 6.78 0.56 3% South Park
UWO Biofilter #11 Add-NR-68
UW-
Oshkosh 2.2 Biofilter 0.37 0.31 0.23 0.09 23% 2.15 1.99 1.54 0.44 21% No
UWO Biofilter #18 Add-NR-69
UW-
Oshkosh 0.9 Biofilter 0.16 0.14 0.09 0.05 33% 0.92 0.86 0.56 0.30 33% No
UWO Biofilter #25 Add-NR-71
UW-
Oshkosh 0.6 Biofilter 0.10 0.09 0.05 0.03 35% 0.58 0.54 0.35 0.19 33% No
UWO Biofilter #27 Add-NR-72
UW-
Oshkosh 1.3 Biofilter 0.19 0.16 0.11 0.05 27% 1.20 1.08 0.76 0.32 26% No
UWO Biofilter #29 Add-NR-73
UW-
Oshkosh 0.6 Biofilter 0.11 0.09 0.06 0.03 30% 0.63 0.59 0.41 0.18 29% No
UWO Biofilter #30 Add-NR-74
UW-
Oshkosh 5.7 Biofilter 0.98 0.84 0.83 0.01 1% 5.67 5.27 5.08 0.19 3% No
UWO Biofilter #34 Add-NR-75
UW-
Oshkosh 0.6 Biofilter 0.11 0.09 0.06 0.03 32% 0.62 0.57 0.38 0.19 31% No
UWO Biofilter
#34S Add-NR-76 UW-
Oshkosh 0.5 Biofilter 0.08 0.07 0.04 0.03 33% 0.50 0.45 0.31 0.15 30% No
UWO Lincoln Hall
Parking Lot Add-NR-77 UW-
Oshkosh 2.8 Biofilter 0.48 0.41 0.29 0.12 26% 2.79 2.60 2.05 0.54 19% No
Washington
Avenue
Apartments
Add-NR-82 Private 0.8 Catch Basin 0.16 0.11 0.10 0.01 4% 0.80 0.64 0.62 0.02 3% No
Winnebago
County Garage Add-NR-85 County 10.2
Wet
Pond/Swale 2.35 1.03 1.00 0.03 1% 7.69 3.56 3.50 0.06 1% South Park
1844 Oshkosh
Avenue Add-NR-2 Private 2.5 Wet Pond 0.19 0.16 0.15 0.00 2% 1.67 1.50 1.43 0.07 4% No
Aurora Medical
Center Add-NR-12 Private 35.8 Wet Pond 6.72 5.84 1.21 4.63 69% 35.35 32.65 11.31 21.34 60% No
Bank First
National Add-NR-13 Private 1.7 Biofilter 0.13 0.11 0.03 0.08 61% 1.15 1.04 0.53 0.50 44% No
Community
Church Inc.Add-NR-20 Private 20.3 Wet Pond 3.85 3.17 0.81 2.37 61% 18.42 16.07 6.32 9.74 53% No
Upper Fox/Wolf TMDL
Table F-1
Additional Non-Regional SMPs with No O&M Agreement Details
Stormwater Management Plan Update
City of Oshkosh, WI
Fox River - Lake
Butte des Morts
to Lake
Winnebago
APPENDIX No O&M Agreement NonRegional SMP Details.xlsx 9/21/2022
Reachshed Non-Regional
SMP Name SMP ID Public/
Private
Treatment
Area (ac)Type of SMP
No
Controls
TSS Load
(tons)
Ex.Cond.
TSS Load
(tons)
w/ Non-
Regional
SMP TSS
Load (tons)
Incremental
TSS Load
Reduction
(tons)
Incremental
TSS Load
Reduction
(%)
No
Controls
TP Load
(lbs)
Ex.Cond.
TP Load
(lbs)
w/ Non-
Regional
SMP TP
Load (lbs)
Incremental
TP Load
Reduction
(lbs)
Incremental
TP Load
Reduction
(%)
Regional SMP
Downstream?
Upper Fox/Wolf TMDL
Table F-1
Additional Non-Regional SMPs with No O&M Agreement Details
Stormwater Management Plan Update
City of Oshkosh, WI
Ken Robl
Conservation Park Add-NR-38 County 169.0 Wet Pond 4.14 3.90 4.04 0.00 0% 50.46 48.82 49.39 0.00 0% No
N. Shore Preserve
Central Basin Add-NR-47 Private 13.5 Wet Pond 1.23 0.95 0.83 0.12 10% 9.70 8.30 7.66 0.64 7% No
N. Shore Preserve
East Basin Add-NR-48 Private 19.2 Wet Pond 1.59 1.27 1.11 0.15 10% 12.87 11.40 10.43 0.98 8% No
N. Shore Preserve
West Basin North Add-NR-49 Private 0.5 Wet Pond 0.05 0.04 0.02 0.02 39% 0.41 0.34 0.17 0.17 41% No
N. Shore Preserve
West Basin South Add-NR-50 Private 1.5 Wet Pond 0.16 0.12 0.10 0.02 11% 1.22 1.01 0.90 0.11 9% No
Turn Key Auto Add-NR-66 Private 1.3 Wet Pond 0.32 0.22 0.04 0.18 57% 1.36 1.01 0.33 0.69 51% No
Winnebago Cty
Sheriffs Dept Add-NR-86 County 68.7 Wet Pond 13.02 11.04 2.45 8.59 66% 62.80 52.41 27.87 24.54 39% No
2800 N. Main St
Redevelopment Add-NR-3 Private 11.8 Wet Pond 2.98 2.67 0.95 1.72 58% 10.51 9.93 5.57 4.36 42% No
Acquire Add-NR-5 Private 1.8 Filter Strip 0.46 0.38 0.40 0.00 0% 1.96 1.68 1.77 0.00 0% No
Advance Auto
Parts Add-NR-6 Private 0.5 Catch Basin 0.13 0.04 0.04 0.00 0% 0.53 0.25 0.25 0.00 0%
Libbey/Nicolet
Watershed - North
Main Street Area
Alro Steel Add-NR-7 Private 18.4 Wet Pond 4.23 4.23 0.80 3.42 81% 13.83 13.83 5.33 8.50 61% No
AP Nonweiler Add-NR-10 Private 7.1 Biofilter 1.82 1.63 1.42 0.21 12% 6.41 6.01 5.44 0.56 9% No
Bergstrom KIA Add-NR-14 Private 4.0 Wet Pond 0.77 0.62 0.04 0.58 76% 3.28 2.64 0.96 1.68 51% No
Casey's General
Store - Jackson Add-NR-17 Private 1.7 Underground 0.45 0.13 0.13 0.00 0% 1.88 0.88 0.88 0.00 0%
Libbey/Nicolet
Watershed - North
Main Street Area
Cobblestone Inn Add-NR-19 Private 3.6 Wet Pond 0.93 0.93 0.11 0.81 88% 3.90 3.90 0.98 2.92 75% No
EAA 1 Add-NR-26 Private 7.0 Wet Pond 0.87 0.65 0.04 0.61 71%4.71 3.09 0.49 2.59 55% No
EAA 2 Add-NR-27 Private 3.9 Wet Pond 0.65 0.57 0.03 0.54 83%3.19 2.69 0.51 2.18 68% No
EAA 3 Add-NR-28 Private 69.6 Wet Pond 7.98 7.40 2.37 5.03 63% 49.62 45.13 20.76 24.37 49% No
EAA 5 Add-NR-29 Private 17.5 Wet Pond 1.99 1.99 0.08 1.91 96% 12.44 12.44 3.48 8.96 72% No
EAA Exhibitor
Pads Gateways
Project
Add-NR-30 Private 38.7 Biofilter 1.74 1.69 1.69 0.00 0% 16.08 15.66 15.65 0.01 0% No
Eagles Club Add-NR-31 Private 1.4
Permeable
Pavement 0.27 0.23 0.19 0.04 14% 1.38 1.25 1.04 0.21 15% No
Fox Valley
Metrology Add-NR-34 Private 1.9
Biofilter/Catch
Basin 0.48 0.43 0.24 0.19 39% 1.69 1.58 1.12 0.46 27% No
Fox-Valley Pro
Basketball Arena Add-NR-35 Private 1.5
Catch Basin /
Perm Pave 0.29 0.23 0.12 0.11 39% 1.24 1.07 0.75 0.32 26% No
Jackson Square
Apartments Add-NR-37 Private 3.5 Wet Pond 0.89 0.25 0.16 0.09 10% 3.13 1.47 1.40 0.07 2%
Libbey/Nicolet
Watershed - North
Main Street Area
Lakeside Plastics Add-NR-39 Private 4.8 Wet Pond 1.23 1.23 0.89 0.34 28% 4.31 4.31 3.51 0.80 19% No
LaSure's Banquet
Facility Add-NR-40 Private 3.8 Swale 0.96 0.55 0.66 0.00 0% 4.05 2.46 2.78 0.00 0% Swale 08
Logan Apartments Add-NR-41 Private 3.3 Wet Pond 0.08 0.01 0.01 0.00 0% 0.98 0.37 0.37 0.00 0%
Fernau Watershed -
North Main Street
Area
Metzler Mini-
Storage Add-NR-44 Private 1.6 Wet Pond 0.42 0.37 0.08 0.29 71% 1.46 1.37 0.66 0.71 49% No
Oshkosh Defense
Parking Lot Add-NR-53 Private 1.3 Wet Pond 0.35 0.31 0.06 0.25 72% 1.22 1.14 0.54 0.60 50% No
Oshkosh Truck Add-NR-54 Private 23.1 Wet Pond 5.41 5.28 1.43 3.86 71% 17.88 17.84 6.51 11.33 63% No
Pacur Inc Add-NR-55 Private 9.9 Wet Pond 2.55 2.28 2.26 0.02 1% 8.97 8.40 8.26 0.14 2% No
Planeview Gas
Station Add-NR-56 Private 5.4 Wet Pond 1.37 1.37 0.87 0.49 36% 5.76 5.76 4.36 1.40 24%
Sanctuary
Aquatics Add-NR-60 Private 1.3 Biofilter 0.33 0.26 0.26 0.00 0% 1.38 1.19 1.20 0.00 0% No
Sioux Prop. Man.
Inc.Add-NR-62 Private 2.3 Wet Pond 0.58 0.00 0.00 0.00 0% 2.46 0.00 0.00 0.00 0% Swale 08
SNC
Manufacturing Add-NR-63 Private 3.0 Swale 0.70 0.28 0.15 0.13 18% 2.28 0.90 0.62 0.28 12% No
Verve Add-NR-78 Private 1.1 Biofilter 0.27 0.08 0.08 0.00 0%1.16 0.52 0.52 0.00 0% Fair Acres
Village Green East Add-NR-80 Private 19.1 Wet Pond 2.32 1.90 0.19 1.72 74% 15.78 14.08 5.84 8.24 52% No
Village Green
West Add-NR-81 Private 7.1 Wet Pond 0.78 0.64 0.03 0.61 77% 5.82 5.21 2.09 3.12 54% No
Winnebago
County CBRF Add-NR-88 County 2.1 Wet Pond 0.40 0.35 0.21 0.13 33% 1.90 1.74 0.93 0.80 42% No
Winnebago Cty
Mental Health
Add-NR-
83/ Add-NR-
84
Couty 447.0 Wet Pond 43.46 35.87 11.33 24.54 56% 303.57 271.37 156.52 114.84 38% No
355 & 425 N
Washburn St Add-NR-4 Private 20.0 Wet Pond 3.85 3.63 1.77 1.86 48% 16.41 15.72 9.49 6.23 38% No
American
Petroleum - BP Add-NR-8 Private 0.9 Wet Pond 0.24 0.18 0.06 0.12 50% 1.00 0.81 0.48 0.33 33% No
Lake Winnebago
Lake Butte des
Morts
APPENDIX No O&M Agreement NonRegional SMP Details.xlsx 9/21/2022
Reachshed Non-Regional
SMP Name SMP ID Public/
Private
Treatment
Area (ac)Type of SMP
No
Controls
TSS Load
(tons)
Ex.Cond.
TSS Load
(tons)
w/ Non-
Regional
SMP TSS
Load (tons)
Incremental
TSS Load
Reduction
(tons)
Incremental
TSS Load
Reduction
(%)
No
Controls
TP Load
(lbs)
Ex.Cond.
TP Load
(lbs)
w/ Non-
Regional
SMP TP
Load (lbs)
Incremental
TP Load
Reduction
(lbs)
Incremental
TP Load
Reduction
(%)
Regional SMP
Downstream?
Upper Fox/Wolf TMDL
Table F-1
Additional Non-Regional SMPs with No O&M Agreement Details
Stormwater Management Plan Update
City of Oshkosh, WI
Blue Rock
Properties Add-NR-16 Private 5.5 Wet Pond 1.41 1.08 0.19 0.89 63% 4.96 3.98 1.49 2.49 50% No
Discount Tire Add-NR-25 Private 1.3 Underground 0.17 0.14 0.07 0.07 41% 1.14 0.99 0.67 0.32 28% No
Fleet Farm Add-NR-32 Private 12.3
Biofilter/Swal
e 2.38 2.24 1.58 0.66 28% 10.13 9.71 7.83 1.88 19% No
Mercy Hospital
North Basin Add-NR-89 Private 47.5 Wet Pond 6.27 4.80 1.53 3.27 52% 40.41 32.69 16.95 15.74 39% No
Mercy Hospital
South Basin Add-NR-42 Private 10.5 Wet Pond 1.95 1.70 0.45 1.25 64% 10.36 9.60 3.73 5.87 57% No
Mercy Hospital
Tower Basin Add-NR-43 Private 7.7 Wet Pond 1.42 1.24 0.24 1.00 70% 7.54 6.99 2.34 4.65 62% No
New Life Church
Basin 1 2 & 4 Add-NR-52 Private 9.2 Wet Pond 1.78 1.57 0.23 1.34 75% 8.44 7.79 3.21 4.59 54% No
New Life Church
Basin 3 Add-NR-51 Private 10.9 Wet Pond 2.11 2.11 0.17 1.94 92% 10.01 10.01 2.50 7.50 75% No
Quail Run Farms
Basin A Add-NR-58 Private 10.8 Wet Pond 0.87 0.69 0.17 0.53 61% 7.37 6.52 3.17 3.36 46% No
Quail Run Farms
Basin B Add-NR-59 Private 19.1 Wet Pond 1.02 0.78 0.19 0.59 58% 9.37 8.24 4.67 3.57 38% No
Sawyer Creek Add-NR-61 Private 92.8 Wet Pond 11.40 9.14 0.80 8.34 73% 76.88 67.36 23.83 43.53 57% No
Viking Electric
Warehouse
Addition
Add-NR-79 Private 6.9 Wet Pond 1.79 1.08 0.42 0.66 37% 6.29 4.60 3.01 1.60 25% No
Sawyer Creek
APPENDIX No O&M Agreement NonRegional SMP Details.xlsx 9/21/2022
City of Oshkosh Stormwater Quality Management Plan
G-1
Oshkosh SWMP Final.docx
Appendix G: Leaf Management Additional Information
1
BUREAU OF WATERSHED MANAGEMENT
PROGRAM GUIDANCE
WATERSHED MANAGEMENT TEAM
Storm Water Runoff Management Program
Wisconsin Department of Natural Resources
101 S. Webster Street, P.O. Box 7921
Madison, WI 53707‐7921
Municipal Phosphorus Reduction Credit for Leaf
Management Programs
02-17-2022
EGAD Number: 3800-2022-01
This document is intended solely as guidance and does not contain any mandatory requirements except where
requirements found in statute or administrative rule are referenced. Any regulatory decisions made by the Department
of Natural Resources in any matter addressed by this guidance will be made by applying the governing statutes and
administrative rules to the relevant facts.
________________________________________________________________________
APPROVED:
2/22/2022
________________________ ________________
Jill Schoen, Acting Director Date
Bureau of Watershed Management
2
3
A. Introduction/Statement of Problem Being Addressed
Permitted Municipal Separate Storm Sewer Systems (MS4s) are subject to an annual
average reduction for the discharge of a pollutant of concern to a surface water that has
an approved Total Maximum Daily Load (TMDL). In many TMDLs one of the pollutants
of concern is phosphorus. Research indicates that phosphorus loads in stormwater in the
fall season may be reduced by leaf collection followed by street cleaning. Municipalities
developing implementation plans to meet TMDL wasteload allocations to quantify
potential benefits of fall leaf management efforts in their plans.
The purpose of this guidance is to clarify the specific conditions and methods for which
numeric credit may be taken by Wisconsin MS4s in demonstrating progress toward
TMDL wasteload allocation expressed as a % reduction in annual average discharge of
phosphorus in urban storm water. This credit is limited to the specific conditions and
methods for which data is available. No numeric credit has been quantified for other land
use types, tree canopies, or management programs, but the Department encourages
municipalities to apply similar leaf management approaches to other land uses and tree
canopy conditions as a source control activity for phosphorus. It is the Department’s
intent to expand the applicability of the guidance to more conditions and programs as
additional studies are completed. This expansion is dependent on availability of funding
for further data collection and evaluation.
B. Objectives
This guidance identifies a percent phosphorus reduction credit which may be taken by
municipalities as part of TMDL modeling and planning and the conditions required to
take that credit.
C. Background and Definitions
Urban trees provide a host of benefits to the residents and workers within a community,
such as energy savings, aesthetics, airborne pollutant reduction, noise reduction, and
providing bird habitat. Trees are also an important part of the hydrologic cycle in both
rural and urban settings. However, urban areas generally have a combination of
impervious surfaces and drainage systems that are directly connected to surface waters.
This creates a delivery system that is very effective at delivering nutrients from leaf litter
to discharge points. Keeping leaf litter out of the delivery system can provide significant
reductions in the discharge of nutrients in urban storm water. Each tree species
contributes a different amount of phosphorus to the stormwater, but since a diverse set of
tree species is beneficial to long-term maintenance of a healthy canopy, this effect is not
being addressed at this time.
While there are many sources of phosphorus in urban stormwater, a primary contributor
is organic detritus, especially in areas with dense overhead tree canopy (Duan et al, 2014;
4
Hobbie et al, 2014; and Kalinosky et al, 2014). Measurement of end-of-pipe phosphorus
concentrations has demonstrated that phosphorus loads in urban stormwater vary
seasonally in certain medium density residential areas, with higher concentrations
coinciding with leaf accumulation on streets (Selbig, 2016). As phosphorus discharges in
stormwater can vary from year to year depending on timing of rainfall events, seasonal
phosphorus loads were modeled over a twenty-year period with WinSLAMM to
determine the average proportion that is discharged in the fall. From this information, it is
estimated that on average 43% of the annual phosphorus load is discharged in the fall.
A variety of public works programs are already in place to collect leaves from the streets
and properties in the fall, but until recently, little was known about the phosphorus
reduction potential of different leaf collection programs. Over the last seven years, the
United States Geological Survey (USGS) conducted a study to characterize reductions of
total and dissolved forms of phosphorus in stormwater through municipal leaf collection
and street cleaning programs in Madison, Wisconsin, USA. Numeric credit for
phosphorus reduction is warranted based on the information.
To estimate the efficiency of leaf management, leaves were collected three to four times
at the test site and collected only once at the end of the fall at the control site. A small
vehicle was used to push the leaves from the terrace into the street and then the leaves
were pushed into garbage trucks. In this guidance, the term ‘terrace’ is used to refer to the
vegetated area between the sidewalk and the curb, or immediately adjacent to the curb
where no sidewalk is present. Within 24 hours of leaf collection, remaining leaf litter in
the street was collected using mechanical street cleaners. The frequency of both push leaf
collection and street cleaning was approximately once every two weeks. Eight end-of-
pipe phosphorus concentration measurements were compared at the test and control sites
during the fall of 2016. Water quality data collected indicate that the push collection and
transfer method coupled with street cleaning within 24 hours resulted in a 40% reduction
of total phosphorus discharge in the fall at the test site versus the control site.
A second year of water quality data with push collection of leaves at the same frequency
(roughly once every other week) coupled with weekly street cleaning using a regenerative
air street cleaner resulted in a 60% reduction of total phosphorus discharge in the fall at
the test site versus the control site. The reduction in total phosphorus may vary with the
type of street cleaner so for this credit, therefore only regenerative air street cleaners may
be used at this time.
To determine the average annual benefit of these leaf management efforts, the reduction
efficiency is multiplied by the percentage of phosphorus load occurring in fall. The
overall phosphorus reduction credit for each study is as follows
• Study 1: 40% x 43% = 17%
• Study 2: 60% x 43% = 25 %
Based on studies to date, the timing of leaf collection and street cleaning appears to be a
critical element. Not all species drop their leaves at the same time, and the timing of
rainfalls is unknown, so the general principle is to keep the streets as clear of leaf litter as
5
feasible. As leaves accumulate on the road and are blown onto the road from the terrace
and adjacent areas, the volume of leaf litter increases to the point that it reduces the
efficiency of street cleaning efforts and bulk collection efforts are needed to supplement
cleaning.
In general, leaf accumulation appears to start in late September (northern Wisconsin) or
early-October (southern Wisconsin). As the timing of leaf fall varies from year to year
and from north to south, local conditions may need to dictate when leaf collection and
associated street cleaning begin. There is an existing effort to predict deciduous tree
behavior for the purposes of tourism, called the Fall Leaf Color Report
(https://www.travelwisconsin.com/fall-color-report). This resource becomes available in
September and may be helpful when planning the start of leaf collection. It is important
to note that collection may need to begin at least 2 weeks before peak fall color is
achieved as different tree species lose their leaves at different times.
D. Guidance Content
A municipality may assume the specified reduction from no controls phosphorus loads
provided all conditions are met. Further evaluation is required to determine how leaf
management may reduce loading to structural best management practices (BMPs) such as
ponds. Therefore, this credit may not be taken in addition to phosphorus reductions from
other BMPs in the drainage area at this time. Municipalities may apply the leaf
management credit to a subset of their residential area if other BMPs are providing more
phosphorus reduction for the remaining area.
Numeric credit may apply to an area if all of the following conditions are met:
1. Land use: Residential land use without alleys. Residential land use with alleys
may be included if the alleys receive the same level of leaf collection and street
cleaning as the streets.
2. Street Section: Curb and gutter streets with storm sewer drainage systems and
light parking densities during street cleaning activities.
3. Tree Canopy: High level of tree canopy determined by one of the following
approaches:
a. An average of one or more medium to large canopy trees located between
the sidewalk and the curb for every 80 linear feet of curb. Where sidewalk
is not present, trees within 15 feet of the curb may be counted toward tree
cover.
b. An average of 40% or greater leaf canopy over the pavement or 45% tree
canopy or greater over the right-of-way determined using leaf-on aerial
photography.
6
In addition, the following legal authorities and policies must also be in place:
1. The municipality has an ordinance prohibiting residents from placement of leaves
in the street.
2. The municipality has a policy stating that residents may place leaves on the
terrace in bags or piles for collection and that they will be removed at the
specified frequency and timing. Leaves may be pushed, vacuumed, or manually
loaded into a fully enclosed vehicle, such as a garbage truck or covered dump
truck. No leaf piles are left in the street overnight. Regular collection limits the
volume of leaves that may blow into the street from adjacent areas.
3. If on-street parking densities are typically greater than light (defined as significant
spacing between parked cars so that street cleaners can easily get to the curb for
most of the curb length), then an ordinance or enforceable policy to restrict
parking during leaf collection and street cleaning activities is needed.
If all the preceding conditions are met, then numeric credit is available for the activities
in Table 1 at the specified frequencies.
Table 1: Leaf Management Options for Numeric Credit
Option Start By
(See also
discussion
below)
Leaf Collection
frequency and timing
Street cleaning
timing
Applicable
annual TP %
Reduction1
1 See Table 2
for last
start date
based on
county.
3-4 times spaced
throughout Late
September, October
and November
Within 24 hours of
leaf collection-
Mechanical broom
or high efficiency
street cleaner2
17%
2 See Table 2
for last
start date
based on
county.
3-4 times spaced
throughout Late
September, October
and November
Weekly with
regenerative air
street cleaner or
vacuum-assisted
street cleaner
25%
1Reduction from a ‘no controls’ condition as modeled in accordance with DNR guidance
2A brush attachment on a skid steer is not an acceptable equivalent
7
Table 2: Latest Acceptable Start Date
County* Start No Later Than
Ashland, Bayfield, Burnett, Douglas, Florence,
Forest, Iron, Langlade, Lincoln, Marinette,
Oneida, Price, Rusk, Sawyer, Taylor, Vilas,
Washburn
September 23
Adams, Barron, Brown, Buffalo, Calumet,
Chippewa, Clark, Columbia, Dodge, Door,
Dunn, Eau Claire, Fond du Lac, Green Lake,
Jackson, Juneau, Kewaunee, LaCrosse,
Manitowoc, Marathon, Marquette,
Menomonie, Monroe, Oconto, Outagamie,
Ozaukee, Pepin, Pierce, Polk, Portage,
Richland, Sauk, Shawano, Sheboygan, St.
Croix, Trempealeau, Vernon, Washington,
Waupaca, Waushara, Winnebago, Wood
October 1
Crawford, Dane, Grant, Green, Iowa,
Jefferson, Lafayette, Kenosha, Milwaukee,
Racine, Rock, Walworth, Waukesha
October 7
*County lists based on USDA planting zones
As the exact timing of leaf fall varies from year-to-year, start of leaf management may be
adjusted based on the following: Street cleaning activities for leaf management efforts
should start when the amount of leaves in the streets with the earliest leaf drop reaches
that depicted with Figure 1 below. It is recommended that bulk leaf collection activities
supplement street cleaning once the amount of leaves in the streets is closer to that
depicted in Figure 2 below and/or residents begin piling leaves on the terrace.
Figure 1: Level of leaf accumulation triggering
start of street cleaning for leaf collection with
weekly sweeping.
Figure 2: Level of leaf accumulation triggering start
of collection in addition to street cleaning
8
At this time, numeric credit for leaf management is not available for other land use types,
lower-density tree canopies, or non-curbed streets. The Department encourages
communities to extend their leaf management efforts into all areas where leaf litter
accumulates in gutters and drainageways and report this as a non-quantifiable source
control effort. Leaf management studies to date have demonstrated that the frequency of
removing the leaves from the street is more important than the method of removing the
leaves. It is difficult to predict the timing of rainfall, so it is important to keep the streets
clear of leaves to limit discharge of phosphorus.
Please see Attachment 1 for an example of how this guidance could be applied in the
context of a TMDL tabular summary.
It is anticipated that additional scenarios will be added as research is completed.
E. References
Duan, S., Delaney-Newcomb, K., Kaushal, S.S., Findlay, S.E.G., Belt, K.T., 2014.
Potential effects of leaf litter on water quality in urban watersheds. Biogeochemistry
121, 61–80. http://dx.doi.org/10.1007/s10533-014-0016-9.
Hobbie, S.E., Baker, L.A., Buyarski, C., Nidzgorski, D., Finlay, J.C., 2014.
Decomposition of tree leaf litter on pavement: implications for urban water quality.
Urban Ecosyst. 17 (2), 369–385. http://dx.doi.org/10.1007/s11252-013-0329-9.
Kalinosky, P., Baker, L.A., Hobbie, S., Bintner, R., Buyarksi, C., 2014. User support
manual: estimating nutrient removal by enhanced street sweeping. Report to the
Minnesota Pollution Control Agency (available at:
http://larrybakerlab.cfans.umn.edu/files/2011/07/Kalinosky-et-al.-2014.-Street-
Sweeping-Guidance-Manual-final-9-24-2014.docx, (accessed April 11th, 2016)).
Selbig, W.R., 2016, Evaluation of leaf removal as a means to reduce nutrient
concentrations and loads in urban stormwater, Science of the Total Environment, 571,
pp. 124 – 133. http://dx.doi.org/10.1016/j.scitotenv.2016.07.003
Selbig, W.R., Buer, N.H., Bannerman, R.T., and Gaebler, P., 2020, Reducing leaf litter
contributions of phosphorus and nitrogen to urban stormwater through municipal leaf
collection and street cleaning practices: U.S. Geological Survey Scientific
Investigations Report 5109, 17 p., https://doi.org/10.3133/sir20205109
9
CREATED:
___________________________ February 22, 2022
Amy Minser, Stormwater Engineer Date
On behalf of the Storm Water Liaison Team
APPROVED:
February 22, 2022
Shannon Haydin, Chief Date
Storm Water Runoff Management Section
Watershed Management Team approved on February 17, 2022.
10
ATTACHMENT 1: Example of How to Apply the Credit for Leaf Management
The fictional Village of Hartsookville currently has an ordinance that prohibits raking
leaves into the street, light on-street parking, collects leaves 3-4 times per season, and
sweeps streets bi-weekly during the fall. It has 3 drainage areas in a TMDL reachshed
for which it is considering taking credit for fall leaf collection. The Village has modeled
its pollution control using WinSLAMM with its existing best management practices,
resulting in the numbers in Table A-1 for Total Phosphorus (TP).
Table A‐1 Total Phosphorus reduction without Leaf Management Credit
Basin TP Yield No Controls
(lbs/yr)
TP Load With
Controls (lbs/yr)
TP Percent Yield
Reduction
DA1 87.1 80.1 8.1
DA2 87.1 60.3 30.7
DA3 82.0 82.0 0.0
Total 256.2 222.4 13.2
Drainage Area 1 (DA1) contains 80 acres medium density residential land use without
alleys and 20 acres strip commercial. This entire area has curb and gutter drainage which
is swept with a Vacuum sweeper once every 4 weeks. The phosphorus reduction from
street cleaning is lower than that offered by leaf management (17%). The village has
confirmed that the residential area meets the tree canopy threshold. From the modeling,
the village has determined that the residential area contributes 65.6 lbs of TP per year for
the drainage area without controls. If the village takes leaf collection credit for the
residential area and the street cleaning credit for the commercial area, the with-controls
TP discharge would be as shown in Table A-2.
Table A‐2: Leaf Management Credit Application to Drainage Area 1
Land use TP Yield No
Controls (lbs/yr)
TP Load With Controls
(lbs/yr)
Percent Yield Reduction
MDRNA 65.6 54.5 17% From Leaf Management
Strip
Commercial
21.5 19.5 9.4% from Street Cleaning per
detailed WinSLAMM output
Total DA1 87.1 74.0 15.1%
11
Drainage Area 2 (DA2) is served by a regional pond that provides more phosphorus reduction
that the leaf management credit, so it does not make sense to take credit for leaf management
for DA2.
Drainage Area 3 (DA3) is not served by a best management practice and is 100% residential land
use meeting the tree canopy requirements. The no‐controls annual TP discharge is 82.0 lbs/yr.
With the leaf management credit, the with controls annual TP discharge would be 82.0 x (1‐
0.17) = 68.1 lbs per year.
Table 3 summarizes the results of the Village’s application of the leaf management credit.
Table A‐3 Total Phosphorus reduction with Leaf Credit
Basin TP Yield No
Controls (lbs/yr)
TP Load With
Controls (lbs/yr)
TP Percent Yield
Reduction
DA1 87.1 74.0 15.1
DA2 87.1 60.3 30.7
DA3 82.0 68.1 17.0
Total 256.2 202.3 21.0
2022 Curbside Brush & Loose Leaf Collection Guidelines
Brush Week:
Brush is defined as tree branches, hedge clippings, garden debris and leaves. The City does not pick
up grass, dirt, root balls, or stumps at any time.
Curbside collection of brush is scheduled on your garbage day during the first full, non-holiday week
of the month from April through December. Brush weeks are underlined on the collection calendar.
Brush should be placed in paper biodegradable bags or bundled and tied. Bundles can be no longer
than 4 feet in length and have branches no larger than 3 inches in diameter. Bags and bundles shall
not exceed 50 pounds in weight. Do not place brush inside garbage or recycling carts for collection.
Place bags and bundles at least 3 feet away from the garbage and recycling carts on the terrace or
driveway apron, no later than 7 am on the scheduled collection day. Do not obstruct the sidewalk.
Spring Cleanup:
Spring Cleanup is 3 consecutive weeks of brush collection, scheduled from April 25th to May 13th. Follow
the same guidelines as the Brush Week collection above.
Fall Loose Leaf Collection:
Fall Loose Leaf Collection runs for 5 consecutive weeks, starting October 17th and ending
November 18th. Collection is scheduled for the day after your garbage day. Loose leaf col-
lection weeks are noted by the orange boxes on the Sanitation Collection Calendar.
Place leaves loosely on the terrace, no bags or brush, no later than 7 am on the day after your
scheduled garbage collection day. Rake the leaves as close to the street as possible. Do not rake
leaves into the street, the gutter line or over the sidewalk. Be mindful of obstructions, such as parked
cars, mailboxes, fire hydrants and power poles. Do not mix brush, grass clippings, other plant materi-
als, dirt, root balls, rocks or stumps with the leaves.
Loose leaf collection may end any time due to weather or equipment issues. Scheduled Loose leaf
collection will end November 18th.
Christmas Tree collection:
Christmas tree collection will take place during 2 weeks in January. Check the
City website for exact dates.
Place trees on the terrace or driveway apron, no later than 7 am on your
scheduled garbage collection day. Artificial or flocked trees will NOT be collected.
Remove all decorations, lights and the tree stand. Trees must not be buried by
snow. Trees must be removed from plastic bags.
Christmas wreaths, garland or swags that contain a metal frame should be
placed in the garbage cart.
Brush, leaves and Christmas trees may also be taken to the City of Oshkosh Yard Waste Drop off Site.
A Yard Waste permit is required.
6
Loose Leaf Collection Day 1st Day 2nd Day 3rd Day 4th Day Final Day
Friday Garbage = Monday Loose Leaf Collection 10/17 10/24 10/31 11/07 11/14
Monday Garbage = Tuesday Loose Leaf Collection 10/18 10/25 11/01 11/08 11/15
Tuesday Garbage = Wednesday Loose Leaf Collection 10/19 10/26 11/02 11/09 11/16
Wednesday Garbage = Thursday Loose Leaf Collection 10/20 10/27 11/03 11/10 11/17
Thursday Garbage = Friday Loose Leaf Collection 10/21 10/28 11/04 11/11 11/18
City of Oshkosh Stormwater Quality Management Plan
H-1
Oshkosh SWMP Final.docx
Appendix H: Potential Regional SMPs Additional
Information
SMP ID Site Name Address Reachshed Reason Removed from Consideration
2/34 Westhaven GC - East S. Westhaven Dr
Sawyer Creek / Fox River - Lake Butte
des Morts to Lake Winnebago
Alternative sites implemented (Westhaven Clubhouse,
Armory, 9th & Washburn)
5 South Park Quarry Pond W. South Park Ave
Fow River - Lake Butte des Morts to
Lake Winnebago
Alternative site implemented (South Park Pond
Expansion)
12 Southland/Josslyn 400 N. Sawyer St
Fow River - Lake Butte des Morts to
Lake Winnebago Storm sewer below lake level
14 East of Bradley / North of
Waukau Ave Bradley St Lake Winnebago
Basin would have inflow from navigable stream, WDNR
typically does not approve permits for on-line basins
17 Hilton Garden Inn Dry Basin
Retrofit 1135 W. 20th Ave Lake Winnebago Proximity to airport, wet ponds discouraged
18 Grambrinus Enterprises Dry
Basin 2850 S. Oakwood Rd Sawyer Creek Alternative site implemented (Oakwood Road)
19 Fernau Ave 2920 N. Main St Lake Winnebago
Alternative site concepts developed (See SMP IDs 37 &
38). Basin would have inflow from navigable stream,
WDNR typically does not approve permits for on-line
basins.
21 Stringham Creek1 Basin
Knapp St 1601 Knapp St Lake Winnebago Environmental concerns (site is closed landfill)
24 Red Arrow Park 613 N. Eagle St Sawyer Creek
Environmental concerns (site is closed landfill);
sanitary sewer conflict
28 South Washburn/STH 44 S. Washburn St Lake Winnebago
Alternative site implemented (South Park Pond
Expansion)
30 Fugleberg Park & Boat
Landing 1942 S. Main St Lake Winnebago Storm sewer below lake level
32 Menominee Park - South 1200 E. Irving Ave Lake Winnebago Storm sewer below lake level
33 Menominee Park - North 1200 E. Irving Ave Lake Winnebago
Storm sewer below lake level; located near school and
athletic fields
35 Westhaven GC - West S. Westhaven Dr Sawyer Creek Rejected by Common Council
36 Libbey Ave/N. Main St N. Main St Lake Winnebago
Alternative site implemented (Libbey Ave - North Main
Street Basin)
City of Oshkosh, WI
Stormwater Management Plan Update
Table H-1
SMP Sites Removed From Consideration - Past Citywide SWMPs
Table H-1_Ponds Removed From Consideration.xlsx 7/15/2022
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
%
%
%
%
%
%
%
%
%
%
%
%
%
%
%
F
o
x RiverSawyer CreekLake Winnebago
Lake Butte des Morts
41
41
5
33
32
21
24
19
17
14
12
30
28
18
36
35
2 / 34
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
Figure H-1SMP Sites Removed from Consideration - Past Citywide SWMPsCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
%SMP Sites Removed fromConsideration
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-1 - Previously Eliminated SMPs.mxd7/15/20220 5,0002,500
Feet
±
Wetlands /
Waterways1 Floodplain1 Environmental2 Natural Heritage
Inventory3 In-Series?Lake Level
Concerns?
Sawyer Creek Sawyer Creek -
9th Ave 41 New Wet
Pond Private Yes Yes None Unknown No No
Could be considered in future. Floodplain and floodway
within parcel. Detailed floodplain analysis would be
needed to determine if site could be feasible. Current
scope of study did not allow detailed evaluation at this
time.
Sawyer Creek Carl Traeger
School 44 Dry Pond
Retrofits School
Indicator soils in existing
dry pond, may qualify as
exemption.
None None Unknown
Upstream of
SMPs 29A and
29B
No
Site is tributary to other preferred sites. Could be
considered in future. Current scope of study did not allow
detailed evaluation at this time.
Lake Butte
des Morts
Algoma Blvd /
Butte des Morts
Dr
45 New Wet
Pond Private
Mapped wetlands
identified adjacent to
site.
None Closed site in
vicinity Unknown No No
Could be considered in future. Other sites were identified
as more feasible/preferable at this time. Current scope of
study did not allow detailed evation at this time.
Sawyer Creek James Road
Detention Basin 46 Dry Pond
Retrofit City
Site is an on-line flood
control basin. Wetland
delineation conducted
as part of site
construction.
Yes None Unknown No No
Site is an online flood control basin. The tributary area is
rural/agricultural land. Flows from stream during large
storm events enter the basin to reduce peak flow and
lower floodplain in City. Detailed site evaluation and
negotiations with WDNR would need to be completed to
determine if use of basin for water quality treatment
would be feasible. Would need to determine how
pollutant reduction would be obtained (trade?). Current
scope of study did not allow detailed evaluation at this
time.
Lake
Winnebago
Gallups-Merritts
Creek / 35th
Ave
47 New Wet
Pond City Yes None
Closed site in
vicinity Unknown No No
Treating runoff from creek was deemed to be not feasible
as it would be an online pond, which is generally not
allowed. Diversion of 35th Ave storm sewer into open
space on west side of creek may be feasible, but drainage
area is small and benefit would be limited.
1Wetlands/Waterways and floodplain screening based on review of available information on WDNR surface water data viewer (https://dnr.wisconsin.gov/topic/SurfaceWater/swdv)
2Envinronmental screening based on review of available information on WDNR RR Sites Map (https://dnr.wisconsin.gov/topic/Brownfields/rrsm.html)
3Natural Heritage Inventory screening conducted for SMPs located on property owned by the City of Oshkosh using WDNR public portal (https://dnr.wisconsin.gov/topic/erreview/PublicPortal.html)
Table H-2
2022 Newly Identified Potential Regional SMP Sites - Detailed Analysis Not Completed
Stormwater Management Plan Update
City of Oshkosh, WI
Evaluation NotesOwner
Screening
Reachshed Regional SMP
Name
SMP
ID
Type of
SMP
Table H-2_2022 Sites Removed.xlsx 7/25/2022
!"#$
!"#$
(/
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
Æ%
Æÿ
Æ%
Æ%
Æÿ
(/
Æÿ
Æ%
^_
^_
^_
^_
^_
^_
F
o
x RiverSawyer CreekLake Winnebago
Lake Butte des Morts
41
41
I
N
K
E
Y
A
26
45
44
91
44
21
45
45
76
45
47
46
44
45
44
41
Figure H-2SMP Sites Removed from Consideration - 2022 Citywide SWMPCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
^_2022 SMP Sites Removed fromConsideration
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-2 - 2022 Eliminated SMPs.mxd7/25/20220 5,0002,500
Feet
±
Wetlands / Waterways1 Floodplain1 Environmental2 Natural Heritage
Inventory3 In-Series? Lake Level Concerns?
Lake Butte des
Morts
Washburn St /
Westowne Ave 6 Wet Pond
Retrofit Private Indicator Soils in existing dry pond,
may qualify as exemption.None None Unknown No No City working on land acquisition for dry pond land to allow construction. Draft plans complete.
Sawyer Creek Pheasant Creek 7
Dry Pond
Retrofit Private
No wetlands/indicator soils
identified. Intermittent stream
identified adjacent to dry pond.
None None Unknown No No Evaluated as part of 9th Avenue reconstruction stormwater study.
Lake
Winnebago Island View Estates 15
Dry Pond
Retrofit Private
Mapped wetlands and indicator
soils in area. May qualify as
exemption.
Yes. Small dam identified
in area.None Unknown No
Yes. Location near Lake
Winnebago. Existing dry pond
near summer high target level.
Pond area is wooded. Existing dry pond is located in back of residential lots. Lots are currently vacant and
for sale.
16A Dry Pond
Retrofit
16B Dry Pond
Retrofit
Lake
Winnebago Bowen Street 26 New Wet Pond Private None None Closed sites in vicinity Unknown
Downstream of Fair Acres
Pond
Yes. Adjacent storm sewer is
submerged.
Existing flow splits upstream in watershed between storm sewer system and Anchorage Channel is
accounted for in analysis. Existing flow split in storm sewer system just west of site is assumed to be
eliminated as part of future storm sewer improvements as part of Anchorage Basin study.
Sawyer Creek Oakwood & 20th Ave 29A New Wet Pond Private None None None Unknown Upstream of 29B No
Sawyer Creek Fox Tail Lane 29B New Wet Pond City
Mapped wetlands and indicator
soils in vicinity of project area.In vicinity of project area. None No Further Actions Downstream of 29A No
Existing sanitary interceptor located along south boundary of pond site. Conceptually pond is located
north of sewer. Existing walking path through pond site would need to be relocated.
Sawyer Creek Westhaven Golf Course
West 35 New Wet Pond Private
Mapped wetlands. Intermittent
stream and existing on-line pond.
Yes. Small dam identified
for existing on-line pond.None Unknown No No
Concept includes diverting storm sewer from Oakwood Road and 9th Avenue. Pond would need to be
located on north side of golf course due to stream and pipe elevations. Pond would need to be lower than
existing pond within golf course due to 9th Avenue storm sewer invert elevations. Could possibly create two
smaller ponds, one near each inlet storm sewer.
Lake
Winnebago Hoffmaster - East 37 New Wet Pond Private
Lake
Winnebago Hoffmaster - West 38 New Wet Pond Private
Lake Butte des
Morts Lakeshore Park 39
Wet Pond
Retrofit City Ponds identified on WWI as
excavated ponds.
Yes. Ponds are within
floodplain.
Open site and closed site
with continuing
obligations on property.
ER Review is
recommended No Pond water levels are maintained
by two pumps.
Ponds are located in a park which was formerly a golf course. Project would involve deepening ponds to
provide settling area and sediment storage. Original depth of ponds unknown and do not know if material
removed would be native material or sediment accumulated in ponds.
Lake Butte des
Morts Riverside - North 40 New Wet Pond City In vicinity In vicinity Closed sites in vicinity
ER Review Strongly
Recommended No No (But site is near Lake Butte des
Morts)
Site is on north edge of parcel with Riverside Cemetery. After detailed evaluation further City internal
discussions identified that potential site is planned for cemetery expansion. Thus, site was eliminated
from consideration.
Sawyer Creek Sawyer Creek - Abbey
Ave 42 New Wet Pond City Yes Yes None
ER Review
Recommended
No. But drainage area
overlaps with Sawyer
Creek - Golden Ave site.
No
Overhead power lines through/adjacent to potential project site. Site located at portion of Abbey Park -
playground located near Westhaven Drive. Tree study required for wooded area. Input from Advisory Park
Board needed. Concept has pond west of the playground, grading and wet pool extends under powerlines.
Sawyer Creek Sawyer Creek - Golden
Ave 43 New Wet Pond City Yes Yes None
ER Review
Recommended
No. But drainage area
overlaps with Sawyer
Creek - Abbey Ave site.
No
Overhead power lines through/adjacent to potential project site. Site located at portion of Abbey Park.
Tree study required for wooded area. Input from Advisory Park Board needed. To create large enough wet
pool area overhead powerline tower would need to be relocated. Pond layout needs to be further evaluated
as part of preliminary design.
Table H-3
Potential Regional SMPs Screening / Feasible Summary
Stormwater Management Plan Update
City of Oshkosh, WI
Reachshed Regional SMP Name SMP ID Type of SMP Owner
Screening
Additional Screening / Feasibility Notes
Sawyer Creek Miles Kimball Private
Mapped wetlands and indicator
soils in area. May qualify as
exemption.
None Closed site Unknown
Pond 16A is upstream of
29B No Assumed pond retrofit remained in current footprint of existing dry ponds.
1Wetlands/Waterways and floodplain screening based on review of available information on WDNR surface water data viewer (https://dnr.wisconsin.gov/topic/SurfaceWater/swdv)
3Natural Heritage Inventory screening conducted for SMPs located on property owned by the City of Oshkosh using WDNR public portal (https://dnr.wisconsin.gov/topic/erreview/PublicPortal.html)
Wetland delineation previously
completed. Navigable stream
between east and west ponds.
None
Closed site with
continuing obligations
identified on property.
Unknown No No Identified/evaluated as part of Fernau Watershed Study.
2Envinronmental screening based on review of available information on WDNR RR Sites Map (https://dnr.wisconsin.gov/topic/Brownfields/rrsm.html)
Pond Analysis - Report Tables.xlsx 8/17/2022
Pollution Reduction / WinSLAMM Analysis Notes
Lake Butte des
Morts
Washburn St /
Westowne Ave 6 Wet Pond
Retrofit 77.3 76.6 16.9 6.4 0.6 73% 1.9 74.0 37.4 50% 0.1
WinSLAMM model developed as part of WDNR grant application for project. City design
includes a phosphorus reduction cell with clear slag. Added removal from slag not accounted
for in analysis due to lack of DNR guidance on performance.
Sawyer Creek Pheasant Creek 7 Dry Pond Retrofit 241.0 86.5 9.3 6.9 1.1 62% 3.3 70.5 58.2 43% 18.0
WinSLAMM model developed as part of West 9th Avenue Reconstruction stormwater analysis.
Includes diversion of storm sewer from West 9th Avenue into detention basin. Removal of
diversion storm sewer would reduce drainage area by approximately 33 acres. Drainage area
includes undeveloped land west of Oshkosh City Limits. Impact of new upstream SMPs that
would be constructed as part of new development are not accounted for.
Lake Winnebago Island View Estates 15 Dry Pond Retrofit 45.4 43.1 3.1 2.4 1.7 93% 2.2 25.8 22.9 62% 13.0
16A Dry Pond Retrofit 21.7 21.7 5.6 5.0 0.8 83% 4.0 19.7 18.4 58% 10.2
16B Dry Pond Retrofit 14.7 14.7 3.1 2.8 0.5 81% 2.2 11.6 10.8 55% 5.6
Lake Winnebago Bowen Street 26 New Wet Pond 229.1 229.1 35.0 27.1 0.9 59% 12.8 206.0 176.1 40% 52.5
Existing storm sewer in submerged below lake level. Assume pond depth is extended to provide
5-ft of water depth below pipe invert elevation. Existing Fair Acres/Murdock wet pond is
upstream. Pond is included in model, reductions are not applied to Fair Acres/Murdock
drainage area. Existing flow splits upstream in watershed between storm sewer system and
Anchorage Channel is accounted for in analysis. Analysis shows 52% of runoff from upstream of
Anchorage Channel goes to Bowen Street pond.
Sawyer Creek Oakwood & 20th Ave 29A New Wet Pond 60.4 60.4 13.3 11.8 1.2 81% 9.4 50.1 47.1 57% 25.7 Accounts for pollutant reduction achieved with only 29A implemented.
Sawyer Creek Fox Tail Lane 29B New Wet Pond 162.1 146.4 21.8 19.4 1.6 80% 15.0 112.4 105.0 56% 55.6 Accounts for pollutant reduction achieved with only 29B implemented.
Sawyer Creek Oakwood & 20th Ave /
Fox Tail Lane
29A &
29B New Wet Ponds 162.1 146.4 21.8 19.4 N/A 83% 15.7 112.4 105.0 56% 56.1
Evaluates the inclusion of both 29A-Oakwood & 20th Ave and 29B-Fox Tail Lane operating in-
series.
Sawyer Creek Westhaven Golf Course
West 35 New Wet Pond 235.2 235.2 23.5 19.5 2.0 82% 15.3 176.8 160.0 61% 91.1
Lake Winnebago Hoffmaster - East 37 New Wet Pond 130.4 110.4 24.9 22.0 2.6 73% 15.2 95.4 88.6 52% 43.0 WinSLAMM model developed as part of Fernau Avenue Watershed SWMP.
Lake Winnebago Hoffmaster - West 38 New Wet Pond 42.7 42.5 9.8 8.3 1.2 74% 5.7 37.6 33.3 53% 15.4 WinSLAMM model developed as part of Fernau Avenue Watershed SWMP.
Lake Butte des
Morts Lakeshore Park 39
Wet Pond
Retrofit 73.9 73.9 5.2 5.0 2.8 95% 4.7 44.7 43.5 68% 29.4
Lake Butte des
Morts Riverside - North 40 New Wet Pond 101.4 65.1 6.8 5.6 1.0 82% 4.3 51.4 45.4 60% 24.6
After detailed evaluation further City internal discussions identified that potential site is
planned for cemetery expansion. Thus, site was eliminated from consideration.
Sawyer Creek Sawyer Creek - Abbey
Ave 42 New Wet Pond 81.2 81.2 10.0 8.2 0.6 80% 6.6 67.2 60.1 62% 33.6
Tributary area to this pond includes overlapping area with 42-Sawyer Creek - Abbey Ave pond.
Assumes diversion sewer from Abbey Ave/Graceland Dr intersection to diverts runoff to west
into pond.
Sawyer Creek Sawyer Creek - Golden
Ave 43 New Wet Pond 76.2 76.2 10.5 8.7 0.7 77% 6.0 64.7 58.0 58% 32.1
WinSLAMM model assumes 30,000 sq. ft. permanent pool. This size permanent pool is not
feasible without relocated overhead powerline tower. Tributary area to this pond includes
overlapping area with 42-Sawyer Creek - Abbey Ave pond.
TMDL
Analyzed
Area (ac)
No Controls
TSS Load
(tons)
Estimated
Additional
TP Load
Reduction
(lbs)
Table H-4
Potential Regional SMPs WinSLAMM Modeling Summary
Stormwater Management Plan Update
City of Oshkosh, WI
Conceptual
Permanent
Pool Area
(acres)
Type of SMP
Total
Drainage
Area (ac)
With
Controls TSS
Load (tons)
Estimated
Pond TSS
Load
Reduction
(%)
Estimated
Additional
TSS Load
Reduction
(tons)
No Controls
TP Load
(lbs)
With
Controls
TP Load
(lbs)
Estimated
Pond TP
Load
Reduction
(%)
Sawyer Creek Miles Kimball
Reachshed Regional SMP Name SMP ID
Pond Analysis - Report Tables.xlsx 8/17/2022
Reachshed Regional SMP Name SMP ID Type of SMP
Estimated
Pond TSS
Load
Reduction
(%)
Estimated
Additional
TSS Load
Reduction
(tons)
Estimated
Pond TP
Load
Reduction
(%)
Estimated
Additional
TP Load
Reduction
(lbs)
Estimated Land
Acquisition Cost
Estimated
Construction Cost
Estimated
Annual
Maintenance
Cost
Estimated
Dredging
Maintenance Cost
Total
Annualized
Cost
Annualized
Cost per Ton
of TSS
Removed
Annualized Cost
per Pound of TP
Removed
Cost Notes
Lake Butte des
Morts
Washburn St /
Westowne Ave 6 Wet Pond
Retrofit 73% 1.9 50% 0.1 $7,000 $295,100 $5,500 $95,000 $21,461 $11,295 $214,606 Construction cost estimate from WDNR grant application utilized and indexed
for inflation (Source: RS Means Historical Cost Indexes)
Sawyer Creek Pheasant Creek 7
Dry Pond
Retrofit 62% 3.3 43% 18.0 $48,000 $935,100 $6,900 $192,000 $50,967 $15,444 $2,831
Cost includes diversion sewer & pavement restoration from 9th Avenue to pond
site along Pheasant Creek Drive. Pavement restoration costs may be reduced is
site is combined with future reconstruction of Pheasant Creek Drive.
Lake Winnebago Island View Estates 15
Dry Pond
Retrofit 93% 2.2 62% 13.0 $43,000 $724,200 $8,300 $300,000 $52,780 $23,991 $4,060
16A Dry Pond
Retrofit 83% 3.6 52% 9.1 $46,000 $375,800 $5,700 $130,000 $25,116 $6,977 $2,760
16B Dry Pond
Retrofit 81% 2.1 54% 5.5 $41,000 $440,800 $4,800 $64,000 $23,049 $10,976 $4,191
Lake Winnebago Bowen Street 26 New Wet Pond 59% 12.8 40% 52.5 $1,462,000 $882,700 $5,300 $180,000 $87,997 $6,875 $1,676
Sawyer Creek Oakwood & 20th 29A New Wet Pond 81% 9.4 56% 25.7 $1,465,000 $941,000 $7,000 $199,000 $92,524 $9,843 $3,600
Sawyer Creek Fox Tail Lane 29B New Wet Pond 80% 15.0 56% 55.6 $0 $1,035,700 $7,900 $273,000 $53,426 $3,562 $961
Sawyer Creek Oakwood & 20th / Fox
Tail Lane
29A &
29B
New Wet
Ponds 83% 15.7 56% 56.1 $1,465,000 $1,976,700 $14,900 $472,000 $145,950 $9,296 $2,602
Sawyer Creek Westhaven Golf Course
Basin 35 New Wet Pond 82% 15.3 61% 91.1 $86,000 $2,155,500 $9,300 $349,000 $96,584 $6,313 $1,060
Lake Winnebago Hoffmaster - East &
West 37 & 38 New Wet Pond 73% 20.9 52% 58.4 $0 $7,418,600 $15,100 $618,000 $279,007 $13,350 $4,778
Construction cost estimate from Fernau Avenue Watershed SWMP utilized and
indexed for inflation (Source: RS Means Historical Cost Indexes). Estimate
includes flood control components of project.
Lake Butte des
Morts Lakeshore Park 39
Wet Pond
Retrofit 95% 4.7 68% 29.4 $0 $429,900 $10,600 $440,000 $44,688 $9,508 $1,520
Lake Butte des
Morts Riverside - North 40 New Wet Pond 82% 4.3 60% 24.6 $0 $597,900 $6,100 $156,000 $32,307 $7,513 $1,313
Sawyer Creek Sawyer Creek - Abbey
Ave 42 New Wet Pond 80% 6.6 62% 33.6 $0 $1,503,400 $5,100 $87,000 $56,803 $8,607 $1,691
Cost includes diversion sewer & pavement restoration from Graceland Drive to
pond site along Abbey Avenue. Pavement restoration costs may be reduced is
site is combined with future reconstruction of Abbey Avenue.
Sawyer Creek Sawyer Creek - Golden
Ave 43 New Wet Pond 77% 6.0 58% 32.1 $0 $589,300 $5,600 $106,000 $29,210 $4,868 $910
Annual maintenance costs based include vegetation maintenance (based on past City projects), nuisance animal trapping (based on past City projects), inlet/outlet grate cleaning ($200 annual per each), misc. erosion repair (24 hrs per site), includes 30% contingency.
Dredging costs include removal of sediment from bottom 2-ft of pond. Material removal cost estimate $30/CY. Fixed site costs (mobilization, erosion control, dewatering, restoration, etc) of $45,000 per acre of pond permanent pool. Includes 30% contingency and 15% design/CRS. Based on past City projects and comparable projects from other
cities.
Annualized cost assumes land and capital cost are distributed over 100-year pond lifespan. Dredging cost annualized over 35-year dredging cycle. Assume 3% interest rate.
Assumptions
Construction cost unit prices based on Oshkosh bid tabs for past projects unless otherwise noted. See Table H-6 for further information.
Land Acquisition costs based on values from past Citywide planning efforts. Costs reviewed by City and deemed appropriate for current study.
Sawyer Creek Miles Kimball
Table H-5
Cost Estimate Summary for Potential Regional SMPs
Stormwater Management Plan Update
City of Oshkosh, WI
Prop Pond Cost Estimates.xlsx 8/17/2022
Est. Qty Total Cost Est. Qty Total Cost Est. Qty Total Cost Est. Qty Total Cost Est. Qty Total Cost Est. Qty Total Cost Est. Qty Total Cost Est. Qty Total Cost Est. Qty Total Cost Est. Qty Total Cost Est. Qty Total Cost Est. Qty Total Cost
Mobilization LS Varies1 1 57,000$ 1 44,000$ 1 23,000$ 1 27,000$ 1 54,000$ 1 57,000$ 1 63,000$ 1 131,000$ 1 26,000$ 1 36,000$ 1 91,000$ 1 36,000$
Excavation CY $13.50 14,047 189,641$ 17,520 236,523$ 7,762 104,790$ 5,686 76,762$ 24,505 330,824$ 27,674 373,597$ 25,243 340,786$ 54,967 742,056$ 14,209 191,822$ 12,848 173,442$ 12,205 164,762$ 14,484 195,539$
Seeding SY $1.25 8,400 10,500$ 4,315 5,394$ 5,867 7,334$ 6,469 8,086$ 4,763 5,953$ 4,639 5,798$ 4,807 6,009$ 8,390 10,487$ 13,289 16,611$ 5,080 6,350$ 3,833 4,792$ 5,609 7,011$
Topsoil – Strip,
Stockpile, Replace SY $2.50 8,400 20,999$ 4,315 10,788$ 5,867 14,668$ 6,469 16,172$ 4,763 11,907$ 4,639 11,597$ 4,807 12,017$ 8,390 20,974$ 13,289 33,222$ 5,080 12,699$ 3,833 9,584$ 5,609 14,022$
Wetland Plantings SY $5.00 968 4,840$ 1,180 5,900$ 800 3,998$ 975 4,876$ 995 4,973$ 972 4,859$ 1,129 5,643$ 1,268 6,338$ N/A -$ 860 4,298$ 658 3,291$ 726 3,628$
Rip-Rap SY $40.00 356 14,222$ N/A -$ N/A -$ N/A -$ 267 10,667$ 356 14,222$ 356 14,222$ 400 16,000$ N/A -$ 356 14,222$ 356 14,222$ 356 14,222$
Clay Liner (2' deep) CY $23.50 4,711 110,707$ 6,824 160,366$ 3,140 73,779$ 5,840 137,246$ 4,624 108,675$ 4,433 104,171$ 6,490 152,518$ 7,172 168,540$ N/A -$ 3,566 83,811$ 2,246 52,775$ 2,652 62,314$
Erosion Matting SY $1.50 8,400 12,599$ 4,315 6,473$ 5,867 8,801$ 6,469 9,703$ 6,312 9,468$ 4,639 6,958$ 4,807 7,210$ 8,390 12,584$ 13,289 19,933$ 5,080 7,620$ 3,833 5,750$ 5,609 8,413$
21" Storm Sewer LF $125 680 85,000$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$
24" Storm Sewer LF $130 N/A -$ N/A -$ N/A -$ N/A -$ 100 13,000$ 75 9,750$ N/A -$ N/A -$ N/A -$ N/A -$ 370 48,100$ N/A -$
30" Storm Sewer LF $145 N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ 75 10,875$
36" Storm Sewer LF $165 N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ 75 12,375$ 1,545 254,925$ N/A -$ N/A -$ N/A -$ N/A -$
42" Storm Sewer LF $175 N/A -$ N/A -$ N/A -$ N/A -$ 100 17,500$ N/A -$ N/A -$ 125 21,875$ N/A -$ N/A -$ 830 145,250$ 75 13,125$
48" Storm Sewer LF $250 N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ 150 37,500$ 685 171,250$ N/A -$
60" Storm Sewer LF $325 N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$
29" x 45" Storm Sewer LF $175 N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ 75 13,125$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$
38" x 60" Storm Sewer LF $275 N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ 75 20,625$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$
4' Dia Storm Manhole VF $475 26 12,350$ N/A -$ N/A -$ N/A -$ N/A -$ 6 2,850$ N/A -$ N/A -$ N/A -$ N/A -$ 0 -$ 8 3,800$
6' Dia Storm Manhole VF $750 N/A -$ N/A -$ N/A -$ N/A -$ 8 6,000$ 6 4,500$ N/A -$ 50 37,500$ N/A -$ 8 6,000$ 64 48,000$ 8 6,000$
8' Dia Storm Manhole VF $1,200 N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ 6 7,200$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$
21" Apron Endwall EA $850 1 850$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$
24" Apron Endwall EA $1,500 N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ 1 1,500$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$
30" Apron Endwall EA $1,750 N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ 1 1,750$
36" Apron Endwall EA $2,000 N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ 1 2,000$ 1 2,000$ N/A -$ N/A -$ N/A -$ N/A -$
42" Apron Endwall EA $2,500 N/A -$ N/A -$ N/A -$ N/A -$ 1 2,500$ N/A -$ N/A -$ 1 2,500$ N/A -$ N/A -$ N/A -$ 1 2,500$
48" Apron Endwall EA $3,000 N/A N/A N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ 1 3,000$ 1 3,000$ N/A -$
29" x 45" Apron Endwall EA $4,500 N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ 1 4,500$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$
38" x 60" Apron Endwall EA $6,000 N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ 1 6,000$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$
Concrete Pavement
Restoration LF $135 680 91,800$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ 1,695 228,825$ N/A -$
Asphalt Path SY $30 N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$ 939 28,167$ N/A -$ N/A -$ N/A -$ N/A -$ N/A -$
Outlet Structure EA $15,000 1 15,000$ 1 15,000$ 1 15,000$ 1 15,000$ 1 15,000$ 1 15,000$ 1 15,000$ 1 15,000$ N/A -$ 1 15,000$ 1 15,000$ 1 15,000$
625,508$ 484,444$ 251,369$ 294,846$ 590,466$ 629,428$ 692,772$ 1,441,779$ 287,587$ 399,942$ 1,005,602$ 394,200$
30% 187,652$ 145,333$ 75,411$ 88,454$ 177,140$ 188,828$ 207,832$ 432,534$ 86,276$ 119,983$ 301,680$ 118,260$
813,160$ 629,778$ 326,780$ 383,300$ 767,606$ 818,256$ 900,604$ 1,874,313$ 373,863$ 519,924$ 1,307,282$ 512,460$
15% 121,974$ 94,467$ 49,017$ 57,495$ 115,141$ 122,738$ 135,091$ 281,147$ 56,079$ 77,989$ 196,092$ 76,869$
935,100$ 724,200$ 375,800$ 440,800$ 882,700$ 941,000$ 1,035,700$ 2,155,500$ 429,900$ 597,900$ 1,503,400$ 589,300$
1Mobilization is equal to 10% of the cost of other line items in estimate.
For SMPs 6 and 37/38 alternative sources of construction cost estimates were utilized. See notes in Table H-5 for source.
Total Amount
Pheasant Creek
(SMP 7)
Construction Sub-Total
Contingency
Westhaven Golf Course
West (SMP 35)Line Item Units Unit Cost
Island View Estates (SMP
15)
Construction Total
Design & CRS
Bowen Street (SMP 26)Oakwood & 20th Ave
(SMP 29A)Fox Tail Lane (SMP 29B)
Table H-6
Potential Regional SMPs Cost Estimates
Stormwater Management Plan Update
City of Oshkosh, WI
Miles Kimball
(SMP 16A)
Miles Kimball Dry Basin
(SMP 16B)
Riverside North
(SMP 40)
Sawyer Creek - Abbey Ave
(SMP 42)
Sawyer Creek - Golden
Ave (SMP 43)
Lakeshore Park
(SMP 39)
Prop Pond Cost Estimates.xlsx 8/17/2022
Expand existing wet pond to north intoexisting dry pond. Permanent pool = 0.6 acres. Drainage area = 77 acres.See Figure H-3a for draft granding plan.N WASHBURN STN KOELLER STW ESTOW NE AVEN WESTHAVEN DREMMERS LNFigure H-3Site 6 - Washburn St / Westowne Ave Wet Pond RetrofitCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Storm Sewer
Drainage Area
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-3 - SMP-6 Washburn-Westowne.mxd0 300150
Feet
±
755755755755
754
753
752
751
750 749 748 747 746
750
749
748
747
746
754753752
754
753
752
751
756
751752753754755758758757
757
758
758
757 757755
754
756758.40757.64757.53757.65757.36757.73758.10757.54756.40756.11758.24 HP757.15757.15756.82757.66MATCH EX.SIDEWALK (TYP.)MATCH EX.SIDEWALK (TYP.)MATCH EX.PAV'T (TYP.)SAW CUT(TYP.)SAW CUT(TYP.)SAW CUT(TYP.)SAW CUT(TYP.)REVERSE SLOPEIN GUTTER (WEST SIDE)PROP. STANDARD 24"CURB & GUTTER (8") REQ'D757.18757.54755.86MATCH EX.PAV'T (TYP.)757.53757.65757.48DRILLED SIDEWALKTIE BARS REQ'D (TYP.)15.5'BOC - BOW
5.0' (TYP)PROP 8" HES CONC DWYAPRON REQ'D (TYP.)PROP 8" HES CONC SIDEWALKTHROUGH DWY REQ'DX10'RX22'RPROP. FLOWLINEGRADE (TYP)PROP. 5" ASPHALT PAV'TW/10" CABC REQ'D30' F-FBEGIN CURB &GUTTER TAPERPROP. 4" CONC. SIDEWALK REQ'DMATCH EX. GRADE (TYP)5 FT CURB HEAD TAPER REQ'DMATCH PROP. BACK OF SIDEWALK5 FT CURB HEAD TAPER REQ'DMATCH PROP. BACK OF SIDEWALKMATCH EX.CURB & GUTTERPAV'T TIES REQ'D(TYP)25'
BOW - HPBENCH MARKS - USGS NAVD 88 DATUMSHEET OF 13CITY CONTRACT 17-13NO.STATIONDESCRIPTIONELEV.DESIGN DATEDESIGN ENGINEERPLAN DESIGN INFORMATIONPLAN REVISIONSDESCRIPTIONDATEBYCITY OF OSHKOSH, WISCONSINJAMES RABE, DIRECTOR OF PUBLIC WORKSSCALE IN FEET:02040DESIGN ENGINEERXX/XX/XXISSUED FOR BID9WESTOWNE AVE & N. WASHBURN STWESTOWNE POND RETROF OVERALL GRADING PLANSTORM: JOHN FERRIS08/28/2017756.07758.90NW BOLT OF MCDONALDS/SHELL SIGN BASETAGBOLT OF HYD E OF MCDONALDS PARKING LOT21LEGENDx.xx%xxxxxxXXX.XXXXX.XXTop of Curb Spot ElevationPavement Spot ElevationExisting Major ContourExisting Minor ContourProposed Major ContourProposed Minor ContourFlow ArrowsExisting Contour GradeProposed Contour GradeN. WASHBURN ST BURIEDELECTRICHWY 21WESTOWNE AVEBURIEDCABLEBURIEDPHONEBURIEDFIBERBM #1758.90BM #2756.07PROPOSEDPROPERTYLINEPROPOSEDPROPERTYLINEPROPOSEDRIGHT-OF-WAYPREVIOUSRIGHT-OF-WAY
Retrofit dry pond to wet pond.Permanent pool = 1.1 acres.Drainage area = 241 acres.
Diversion sewer from 9th Avenueto wet detention basin.S OAKWOOD RDW 009TH (NINTH) AVE
MOCKINGBIRD WAY FAIRFAX STRUSCHFIELD DRPHEASANT CREEK DRREBECCA RUN TIMOTHY TRHOMESTEAD DR
HAYWARD AVE
F
O
X FI
R
E D
R
HEIDI HAVEN DRWHEATFIELD WAYKIRKWOOD DRJUDY LEE DRQ
U
AIL R
U
N D
R
JOHN MOORE DRJUDY LEE CTWELLINGTON DRBAILEY CTHUNTER S PLCASEY TRWELLINGTON CTHEIDI HAVEN CTLINDEN OAKS DRTIMOTHY TR S OAKWOOD RDFigure H-4Site 7 - Pheasant Creek Dry Pond RetrofitCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Storm Sewer
Drainage Area
Conceptual Permanent Pool Area
9th Avenue Diversion Sewer
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-4 - SMP-7 PheasantCreek.mxd0 300150
Feet
±
!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(Pond Normal Water Elev. = 776.75Permanent Pool Area = 1.14 acresAdded Storage Volume = 3.5 acre-feet36" Storm21" Storm24" StormDiversion Sewer Inv. Elev. = 780.45Overflow Sewer Inv. Elev. = 782.2Backflow from Pond Occurs in Larger StormsThrough Diversion Sewer & Into 9th AvenueWith Inclusion of InterconnectionThere is Flexibility in Sizing of Sewers.W 9th AvePhe as ant C re ek D r
Heidi Haven DrBailey CtHomestead DrHunters PlWheatfield WayFox Fire DrQuail Run DrJudy Lee DrLegend!(Storm StructuresExisting CulvertExisting Storm Sewer9th Ave Storm SewerImproved Sewer - Adjacent StreetsPheasant Creek Dr Diversion SewerGrass SwaleNormal Water LevelConceptual Contours (1')Existing Contours (2')Parcels11/18/20200 50 100FeetFigure 8Pheasant Creek Drive Dry DetentionBasin Retrofit - Low Flow Diversion Concept9th Avenue ReconstructionCity of Oshkosh, WI
Retrofit dry pond to wet pond.Permanent pool = 1.7 acres. Drainage area = 45 acres.
SUNNYVIEW RDSHERMAN RDZACHER DR
CTH AS
HA
M
BEAU DR
E CTH Y CEDAR VIEW DRHILLWOOD RUNMARWAY CTISLAND VIEW DRISLAND ESTATES CT
Figure H-5Site 15 - Island View Estates Dry Pond RetrofitCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Storm Sewer
Drainage Area
Conceptual Permanent Pool Area
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-5 - SMP-15 IslandView.mxd0 300150
Feet
±
Site 16BRetrofit dry pond to wet pond.Permanent pool = 0.5 acres. Drainage area = 14.7 acres.
Site 16ARetrofit dry pond to wet pond.Permanent pool = 0.8 acres. Drainage area = 21.7 acres.
S O
A
K
WO
O
D R
D
BADGER AVEME
A
D
OW P
A
R
K
D
R
Figure H-6Sites 16A & 16B - Mile Kimball Dry Pond RetrofitsCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Storm Sewer
Drainage Area
Conceptual Permanent Pool
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-6 - SMP-16A16B MilesKimball.mxd0 300150
Feet
±
Construct new wet pond.Permanent pool = 0.9 acres. Drainage area = 229 acres.
Storm sewer flow split. Low flows go east towards conceptual detention basin location. High flows go north in Anchorage Channel.EVANS STN MAIN STGROVE STBOWEN STJACKSON STHARRISON STWISCONSIN STVIOLA AVE
BEECH STCEDAR STE NEVADA AVE
LIBERTY STONTARIO STW MURDOCK AVE
W NEW YORK AVE
E MURDOCK AVE
WESTERN STJEFFERSON STE NEW YORK AVE
HOBBS AVE
W BENT AVE
GRAND STCONGRESS AVE ASHLAND STBROAD ST EE CUSTER AVE
POWERS STMONROE STBURDICK STMOUNT VERNON STCENTRAL STBROAD ST WKENTUCKY STEASTMAN STW GRUENWALD AVE
STILLWELL AVE
W NEVADA AVE
E TENNESSEE AVE
E GRUENWALD AVE
HURON AVE
W CUSTER AVE
ANNEX AVE
TITAN CTALLEY
STANLEY AVE
W L IN W O O D A V E
SARATOGA AVE
DOCTORS CT
SHELTER CTGEHRES CTMOUNT VERNON STJEFFERSON STE TENNESSEE AVE
W BENT AVE
POWERS STCENTRAL STJEFFERSON STE CUSTER AVE
KENTUCKY STW NEVADA AVE
Figure H-7Site 26 - Bowen Street Net Wet PondCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Storm Sewer
Drainage Area
Conceptual Permanent Pool
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-7 - SMP-26 BowenSt.mxd0 600300
Feet
±
Construct new wet pond.Permanent pool = 1.2 acres. Drainage area = 60.4 acres.
W 020TH (TWENTIETH) AVE
S OAKWOOD RDBADGER AVEUNIVERSAL STFigure H-8Site 29A - Oakwood Road & 20th Avenue New Wet PondCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Storm Sewer
Drainage Area
Conceptual Permanent Pool Area
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-8 - SMP-29A Oakwood20th.mxd0 350175
Feet
±
Construct new wet pond.Permanent pool = 1.6 acres. Drainage area = 162 acres.
W 020TH (TWENTIETH) AVE S OAKWOOD RDNEWPORT AVE
UNIVERSAL STBADGER AVEM O N T C L A I R P L MARICOPA DRS WESTHAVEN DRBERNHEIM STCHATHAM DRGLOBAL PKW YARLINGTON DRWOODSTOCK STME
A
D
OW
P
A
R
K
D
R CRESTVIEW DRFOX TAIL LA
HUNTERS GLEN DRSAWYER CREEK DR
BRENTWOOD DRTEMPLETON PLCASEY TRW E S T H A V E N C IR
ALLERTON DR
LENNOX STNEWPORT CT
CHATHAM CTFigure H-9Site 29B - Fox Tail Lane New Wet PondCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Storm Sewer
Drainage Area
Conceptual Permanent Pool Area
Sanitary Interceptor Sewer
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-9 - SMP-29B FoxTailLane.mxd0 700350
Feet
±
Construct new wet pond.Permanent pool = 1.6 acres. Drainage area = 162 acres.
Construct new wet pond.Permanent pool = 1.2 acres. Drainage area = 60.4 acres.
W 020TH (TWENTIETH) AVE S OAKWOOD RDNEWPORT AVE
UNIVERSAL STBADGER AVEM O N T C L A I R P L MARICOPA DRS WESTHAVEN DRBERNHEIM STCHATHAM DRGLOBAL PKW YARLINGTON DRWOODSTOCK STME
A
D
OW
P
A
R
K
D
R CRESTVIEW DRFOX TAIL LA
HUNTERS GLEN DRSAWYER CREEK DR
BRENTWOOD DRTEMPLETON PLCASEY TRW E S T H A V E N C IR
ALLERTON DR
LENNOX STNEWPORT CT
CHATHAM CTFigure H-10Site 29A & 29B - Oakwood & 20th Avenue / Fox Tail Lane New Wet PondsCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Storm Sewer
Drainage Area
Conceptual Permanent Pool Area
Sanitary Interceptor Sewer
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-10 - SMP-29A-29B.mxd0 700350
Feet
±
Construct new wet pond.Location would need to be determined as part of design process and through collaboration with golf course.Permanent pool = 2.0 acres. Drainage area = 235 acres.
W 009TH (NINTH) AVE
S KOELLER STW 020TH (TWENTIETH) AVE S WASHBURN STS OAKWOOD RDMARICOPA DRS WESTHAVEN DRNEWPORT AVE
ALLERTON DRREICHOW STVILLAGE LA GREENFIELD TROSBORN AVEHERITAGE TRM O N T C L A IR P LFAIRFAX STVILLA PARK DRRUSCHFIELD DRPHEASANT CREEK DRREBECCA RUN
BERNHEIM STTIMOTHY TRCHATHAM DRCOVINGTON DRMOCKINGBIRD WAY MORELAND STCUMBERLAND TRARLINGTON DR THORNTON DRDEERFIELD DRHOMESTEAD DR
WOODSTOCK STARDMORE TRCRESTVIEW DRFOX TAIL LA S WESTFIELD STHAYWARD AVE
H E ID I H A V E N D R
WHEATFIELD WAYHUNTERS GLEN DRCANDLELIGHT CTFOX FIRE DRSAWYER CREEK DR
BRENTWOOD DRJUDY LEE DRTEMPLE TO N PL CA
MDEN L
AKIRKWOOD DRLILAC STGRACELAND DRARCADIA AVE
GALWAY CTDICKINSON AVE
KINGSTON PL
CAPITAL DRWELLINGTON DRMENARD DR
WESTHAVEN CIRJOHN MOORE DRCASEY TRVIKING PLLENNOX STNEWPORT CT
W E L D O N C T
CHATHAM CTKILLARNEY CT
WILDERNESS PL
S WESTFIELD STS WESTHAVEN DRS OAKWOOD RDFigure H-11Site 35 - Westhaven Golf Course West New Wet PondCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Storm Sewer
Drainage Area
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-11 - SMP-35-Westhaven.mxd0 700350
Feet
±
Æÿ
Construct new wet ponds.East permanent pool = 2.6 acresEast drainage area = 130.4 acresWest permanent pool = 1.2 acresWest drainage area = 42.7 acresSee Figure H-12a for concept layout.
ACTH AN MAIN STJACKSON STVINLAND STMOSER STE SNELL RD
W SNELL RD
OLSON AVE
FARMINGTON AVE
COZY LASHADOW LACHRISTIAN DR
E FERNAU AVEW FERNAU AVELOGAN DRFREEDOM AVE EICHSTADT RDMACARTHUR RD
RIDGE LA
BIRCH LA
MILLER LA SHERMAN RDLOUISE CTSUMMERSET WAYHARBOR BAY RDDRIFTWOOD LA
KEENVILLE LAZION STPARKVIEW CT
HARVEST DRGOLDEN IRIS DR PURPLE CREST CTFigure H-12Sites 37 & 38 - Hoffmaster - East and West New Wet PondsCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Storm Sewer
Drainage Area
Conceptual Permanent Pool Area
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-12 - SMP-37-38 Hoffmaster.mxd0 600300
Feet
±
!!!!!!!!!!!!!!!!#!!!!!!!!!!!!!!!!!!!!!!!!!!Fernau CrHoffmasterDiversion StructureNorth BranchDiversion StructureSouth BranchDiversion StructureNorth BranchBypass SewerSouth BranchBypass SewerMain StemBypass SewerEast Pool OutletWest Pool OutletMoser StreetInlet SewerFernau AveInlet SewerMain StInlet SewerMain St CulvertRelocationN Main StE Fernau AveMoser StW Fernau Ave3634x53
30242724x382 -4 8
4238x6048
48x764x636 364x6424x6274 8 x 7 6 48x762436244x6242448x7642424x6244x6
4x648
LegendLegendLegendLegendXPSWMM Model Input!Manhole#Detention BasinBridge/CulvertPipePrivate PipeOpen Channel/SwaleParcelsProposed Storm Sewer ImprovementsAbandon Existing Storm SewerNew Storm SewerRedirect Detention Basin OutletStream ImprovementsFuture Development ImprovementsReplace Existing Storm SewerDetention Basin LayoutDeep Pool Area (5')Shallow Pool Area (1')Dry Storage AreaDetention Basin - Top of BankContours (1')Document Path: C:\Users\mwegner\Documents\Projects\Oshkosh City of\146204_Fernau Basin Stmwater Study\GIS\MXD\Report Figures\Figure 5-5_Hoff_Layout.mxdFigure 5-5Proposed Hoffmaster Wet Detention Basin LayoutFernau Avenue Watershed Regional SWMPCity of Oshkosh, WI4/28/20170 62.5 125Feet±Air Photo: City of Oshkosh, 2015
Utilize existing Lakeshore Park ponds.Excavate ponds 5-ft below existing pipeinvert elevations. Cumulative Permanent pool = 2.75 acres. Drainage area = 77 acres.
OSHKOSH AVE
ALLEY
PUNHOQUA STR
AIN
B
O
W
D
R
FOX STV
E
T
E
R
A
N
S
T
R
GRAHAM AVE
N EAGLE STCATHERINE AVE
RATH LA
DOVE STN KO ELLER STN WESTFIELD STFILLMORE AVE
BUCHANAN AVE
REPP AVE
N SAWYER STMAPLE AVE
LOCUST STJOSSLYN STNIMROD CTO S H K OSH A VEN EAGLE STALLEY ALLEYN EAGLE STALLEY
ALLEY
Figure H-13Site 39 - Lakeshore Park Wet Ponds RetrofitCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Storm Sewer
Drainage
Conceptual Permanent Pool
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-13 - SMP-39 Lakeshore.mxd0 300150
Feet
±
Construct new wet pond.Permanent pool = 1.0 acres. Drainage area = 101 acres.AL
GOMA
B
L
V
DCLOVER STMINERVA STHAMILTON STW PACKER AVE
SHERIDAN STMARQUETTE AVE
PARKSIDE DRPLYMOUTH STMORGAN AVEKAITLYNN DRKIENAST AVE
KAITLYNN CTPARKSIDE CT
Figure H-14Site 40 - Riverside - North New Wet PondCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Storm Sewer
Drainage Area
Conceptual Permanent Pool Area
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-14 - SMP-40 Riverside.mxd0 450225
Feet
±
Construct new wet pond.Permanent pool = 0.6 acres. Drainage area = 81.2 acres.
Construct new storm sewerto west to divert runoff fromintersection of Graceland Dr and Abbey Ave to SMP.
ABBEY AVE
W 009TH (NINTH) AVE GREENFIELD TRS WASHBURN STGRACELAND DRS WESTHAVEN DRGOLDEN AVE
HERITAGE TRHENNESSY STKATY CT
KINCAID AVE
G R A C E L A N D C T
WESTHAVEN CT
Figure H-15Site 42 - Sawyer Creek - Abbey Ave New Wet PondCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Storm Sewer
Drainage Area
Conceptual Permanent Pool
Proposed Storm Sewer
ATC Power Lines
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-15 - SMP-42.mxd0 250125
Feet
±
Construct new wet pond.Permanent pool = 0.7 acres. Drainage area = 76.2 acres.
Overhead power poleneeds to be relocatedto allow pond construction
ABBEY AVE
W 009TH (NINTH) AVE GREENFIELD TRS WASHBURN STGRACELAND DRS WESTHAVEN DRGOLDEN AVE
HERITAGE TRHENNESSY STKATY CT
KINCAID AVE
G R A C E L A N D C T
WESTHAVEN CT
Figure H-16Site 43 - Sawyer Creek - Golden Ave New Wet PondCity of OshkoshStormwater Quality Management Plan
Legend
City Limits
Storm Sewer
Drainage
Conceptual Permanent Pool
ATC Power Lines
Path: V:\154820 - Oshkosh SWM - TMDL Compliance - 20 - 21\MXDs\Figures\Report Figures\Figure H-16 - SMP-43-GoldenAve.mxd0 250125
Feet
±
Reachshed Regional SMP Name SMP ID Owner
Treatment
Area (ac)Type of SMP
No Controls
TSS Load
(tons)
With Controls
TSS Load
(tons)
TSS Load
Reduction
(tons)
TSS Load
Reduction
(%)
No Controls
TP Load
(lbs)
With Controls
TP Load
(lbs)
TP Load
Reduction
(lbs)
TP Load
Reduction
(%)
Potential
lbs of TP
Removal at
85.6%
Enhanced Settling Treatment Potential Notes
Armory Reg-1 City 415.4 Wet Pond 86.3 6.3 80.0 93% 355.5 74.6 280.8 79% 23.5
Existing site achieves high level of control, incremental benefit of adding
enhanced settling treatment is limits.
City Hall Reg-2 City 106.9 Wet Pond 15.0 7.2 7.9 52% 99.6 61.5 38.0 38% 47.2 N/A - Underground wet detention basin
South Park Reg-3 City 660.1 Wet Pond 111.4 45.4 66.0 59% 572.0 247.6 324.4 57% 165.2 Within park, likely challenge with available space, ability to deepen
E Nevada Ave Reg-4 City 94.7 Lift Station 10.6 7.7 2.9 27% 77.1 63.6 13.4 17% 52.5 N/A - Lift Station
Fair Acres/Murdock Reg-5 City 93.0 Wet Pond 16.0 4.7 11.3 71% 86.4 38.8 47.6 55% 26.4 Multiple inlets.
Fernau Watershed - North
Main Street Area Reg-6 City 151.1 Wet Pond 30.1 3.9 26.3 87% 129.2 48.1 81.2 63%29.5 Groundwater & rock - difficult to deepen
Libbey-Nicolet Reg-7 City 341.4 Wet Pond 55.7 15.6 40.0 72% 289.4 135.8 153.6 53% 94.1 Groundwater - difficult to deepen, multiple inlets
Melvin Ave Reg-8 City 110.8 Lift Station 13.3 9.1 4.1 31% 93.9 73.8 20.0 21% 60.3 N/A - Lift Station
North High School Area Reg-9 City 77.1 Wet Pond 8.9 1.2 7.6 86% 62.5 20.8 41.7 67% 11.8
Located U/S of Libbey-Nicolet, likely most effective to implement downstream.
Rock - difficult to deepen. Low incremental TP reduction benefit.
9th & Washburn Reg-10 City 293.6 Wet Pond 32.4 5.4 26.9 83% 217.0 84.4 132.6 61% 53.2 Wetlands within pond area. Single primary inflow point.
Oakwood Road Reg-11 City 56.9 Wet Pond 13.2 1.0 12.2 92% 47.7 17.1 30.6 64% 10.3 Low incremental TP reduction benefit.
Westhaven Club House Reg-12 City 72.6 Wet Pond 7.2 0.3 6.9 96%55.0 14.8 40.1 73% 6.9
Located U/S of 9th & Washburn, likely most effective to implement downstream.
Low incremental TP reduction benefit.
Green shading represents sites selected for additional evaluation.
Preferred Enhanced Phosphorus Site Characteristics:
1. Space for treatment system - need area for small building with equipment
2. Electrical - System needs three phase electrical to site.
3. Single (or a primary) inlet - Coagulant is added in a mixing chamber in pipe.
4. Access for regular O&M at equipment building, mixing chamber, access for delivery of coagulant to building
5. Provisions for dredging and disposal of floc generated (occurs approximately every 1-3 years). Others projects dredge/pump to sanitary. Alternative is to dewater on-site and find disposal location.
6. Pond depth - prefer deeper pond (8+ ft), thus would like ability to further excavate pond. Deeper pond allows better floc settling and less frequent dredging.
Lake Winnebago
Sawyer Creek
Fox River - Lake Butte
des Morts to Lake
Winnebago
Table H-7
Enhanced Settling Site Selection Initial Screening Review
Stormwater Management Plan Update
City of Oshkosh, WI
Enhanced P Analysis.xlsx 9/21/2022
Reachshed Regional SMP Name SMP ID
Treatment
Area (ac)
No Controls
TSS Load
(tons)
Existing
Pond TSS
Load
Reduction
(%)
No Controls
TP Load
(lbs)
TP Load
Reduction
(%)
Potential tons of
TSS Removal at
90% TSS Removal
Rate
Potential lbs of TP
Removal at
85.6% TP
Removal Rate
Coagulant System
Capital Cost
(A) Annualized
Capital Cost
(B) Base Annual
Operation and
Maintenance
Costs
(C) Variable
Annual
Maintenance
Cost
(D) Total
Annualized Cost
(A+B+C)
Annualized
Cost/Ton of
Incremental TSS
Removed
Annualized
Cost/Pound of
Incremental TP
Removed
Fair Acres/Murdock Reg-5 93.0 16.0 71% 86.4 55% 3.1 26.4 $1,193,712 $43,012 $26,520 $11,179 $80,712 $26,017 $3,061
Fernau Watershed - North
Main Street Area Reg-6 151.1 30.1 87% 129.2 63% 0.9 29.5 $1,284,920 $47,028 $26,520 $19,149 $92,697 $107,967 $3,148
Libbey-Nicolet Reg-7 341.4 55.7 72% 289.4 53% 10.1 94.1
North High School Area Reg-9 77.1 8.9 86% 62.5 67% 0.4 11.8
10.4 105.9
9th & Washburn Reg-10 293.6 32.4 83% 217.0 61% 2.2 53.2
Westhaven Club House Reg-12 72.6 7.2 96% 55.0 73% 0.0 6.9
2.2 60.1
Residence Time Criteria Evaluation:
Fair Acres/Murdock:
Total Storage Volume: 17.3 acre-feet
Required Storage Volume: Largest event = 48.6 acre-feet; 5th largest event = 33.7 acre-feet.
Fernau Watershed - North Main Street Area
Total Storage Volume: 77.9 acre-feet
Required Storage Volume: Largest event = 90.7 acre-feet; 2nd largest event = 68.9 acre-feet; 5th largest event = 61.5 acre-feet.
Libbey-Nicolet:
Total Storage Volume: 67.4 acre-feet
Required Storage Volume: Largest event = 68.9 acre-feet; 2nd largest event = 37.2 acre-feet; 5th largest event = 33.2 acre-feet.
9th & Washburn:
Total Storage Volume: 86.9 acre-feet
Required Storage Volume: Largest event = 87.3 acre-feet; 2nd largest event = 61.5 acre-feet; 5th largest event = 52.5 acre-feet.
Potential Site Constraints/Assumptions:
All sites: Assumed pond depth increase not required. Additional analysis/preliminary design evaluation should consider benefits of increased depth.
Fair Acres/Murdock:
Footprint does not allow pond to be deepened to meet storage volume requirement
Fernau Watershed - North Main Street Area
Treatment building location identified at northeast corner of the site in proximity to Main Street and close to one of the pond inlets.
Rock within the footprint of the pond reduces normal water depth in northwest corner of pond and impacts storage volume/residence time calculations.
Not feasible to deepen pond due to rock and groundwater dewatering system within pond.
Libbey-Nicolet:
Wet pond is located north of a dry pond that provides additional storage and flood control. How the backwater and flow between the ponds function needs to be further evaluated. Analysis assumes that inlet from dry pond is treated with coagulant.
Identified northeast corner of wet pond for building location. This location is in close proximity to street and one of the pond inlets. Other locations do not have adequate space for a building and result in difficult access.
Not feasible to deepen pond due groundwater dewatering system within pond.
9th & Washburn:
Treatment building location identified at northeast corner of the site in proximity to Washburn Street. Access and space does not allow building to be placed close to primary inlet at south side of site.
Analysis assumed only the primary inlet (5'x8' box culvert) is treated with coagulant. Smaller inlets surrounding pond are not treated and it is assumed pollution loads from those pipes is negligible.
The southern portion of the pond is a dry storage area where wetlands were present at the time of construction. Wetland permitting requirements need to be further considered.
Table H-8
Enhanced Phosphorus Reduction Analysis Details
Stormwater Management Plan Update
City of Oshkosh, WI
$78,707
$1,283,032 $38,658
$26,520 $39,019 $144,246 $13,828 $1,362
$26,520 $20,991 $86,168 $39,148 $1,434
Lake Winnebago
Sawyer Creek
Libbey-Nicolet Total
9th & Washburn Total
$2,088,840
Enhanced P Analysis.xlsx 9/21/2022
Est. Qty Total Cost Est. Qty Total Cost Est. Qty Total Cost Est. Qty Total Cost
1 Mobilization LS Varies 1 60,000$ 1 122,000$ 1 70,000$ 1 75,000$
2 Pond Retrofit Cost LS Varies N/A -$ N/A1 60,000$ N/A2 138,675$ N/A -$
3 1-inch HDPE Coagulant Feed Line LF 25$ 1,150 28,750$ 1,750 43,750$ 225 5,625$ 1,380 34,500$
4 WQ monitoring stations and equipment EA 28,500$ 2 57,000$ 2 57,000$ 2 57,000$ 2 57,000$
5 1-inch PRGS Conduit & Signal Cable to Point of Flow Measurement LF 40$ 1,150 46,000$ 1,750 70,000$ 225 9,000$ 1,380 55,200$
6 Coagulant Tank Fill Structures / Valves EA 3,500$ 1 3,500$ 1 3,500$ 1 3,500$ 1 3,500$
7 Coagulant Tank Fill Line, 3-inch PVC LF 30$ 100 3,000$ 100 3,000$ 100 3,000$ 100 3,000$
8 Bldg Drain Line, 6-inch PVC LF 50$ 20 1,000$ 20 1,000$ 20 1,000$ 20 1,000$
9 Floc Discharge Structure / Assembly EA 4,500$ 1 4,500$ 1 4,500$ 1 4,500$ 1 4,500$
10 Floc Discharge Line to Sanitary Sewer, 6-inch PVC LF 50$ 125 6,250$ 75 3,750$ 280 14,000$ 100 5,000$
11 1-inch Water Service LF 40$ 100 4,000$ 100 4,000$ 280 11,200$ 80 3,200$
12 Flow Measurement Location (includes valves, piping, structure, etc) EA 35,000$ 1 35,000$ 3 105,000$ 1 35,000$ 2 70,000$
13 Coagulant Addition Location (structure, flash-mixer, etc.)EA 100,000$ 1 100,000$ 3 300,000$ 1 100,000$ 2 200,000$
14 Bldg Piping, Valves, & Appurtenances LS 10,000$ 1 10,000$ 1 10,000$ 1 10,000$ 1 10,000$
15 3,000 Gallon Double Wall FRP Tank, Heated, & Leak Detection System EA 15,000$ 1 15,000$ 1 15,000$ 1 15,000$ 1 15,000$
16 Coagulant Pump & Control Panel EA 100,000$ 1 100,000$ 3 300,000$ 1 100,000$ 1 100,000$
17 Coagulant Flow Meter EA 15,000$ 1 15,000$ 3 45,000$ 1 15,000$ 1 15,000$
18 Equipment Bldg (concrete block w/ shingle roof) SF 150$ 528 79,200$ 660 99,000$ 528 79,200$ 528 79,200$
19 Gravel Driveway SY 15$ 267 4,000$ 167 2,500$ 233 3,500$ 171 2,567$
20 Bldg Electrical / HVAC LS 40,000$ 1 40,000$ 1 40,000$ 1 40,000$ 1 40,000$
21 Telemetry LS 25,000$ 1 25,000$ 1 25,000$ 1 25,000$ 1 25,000$
22 Electrical Service to Pump building LS 25,000$ 1 25,000$ 1 25,000$ 1 25,000$ 1 25,000$
662,200$ 1,339,000$ 765,200$ 823,667$
198,660$ 401,700$ 229,560$ 247,100$
860,860$ 1,740,700$ 994,760$ 1,070,767$
172,172$ 348,140$ 198,952$ 214,153$
1,033,032$ 2,088,840$ 1,193,712$ 1,284,920$
Est. Qty Total Cost Est. Qty Total Cost Est. Qty Total Cost Est. Qty Total Cost
1 Weekly Site Visits & Testing (1 visit / week, 1 person, 2 hrs / visit) HRS 50$ 104 5,200$ 104 5,200$ 104 5,200$ 104 5,200$
2 Equipment / Supplies ($100 / month)LS 1,200$ 1 1,200$ 1 1,200$ 1 1,200$ 1 1,200$
3 Coagulant Purchase (10 gal of Coagulant / 1.0 ac-ft of runoff) GAL 5.00$ 1,675 8,374$ 3,195 15,975$ 833 4,164$ 1,512 7,562$
4 Floc Removal and Transfer to Sewer HRS 50.00$ 20 1,000$ 32 1,600$ 16 800$ 20 1,000$
5 Floc/Sediment Disposal (1075 gal of Sediment / 1.0 ac-ft of runoff) GAL 0.03$ 180,030 5,401$ 343,452 10,304$ 89,534 2,686$ 162,583 4,877$
6 Power (50 kWh / 1.0 ac-ft of runoff)kWh 0.10$ 8,374 1,372$ 15,975 2,136$ 4,164 949$ 7,562 1,291$
7 WQ Monitoring (20 events/yr.)Events 700$ 20 14,000$ 20 14,000$ 20 14,000$ 20 14,000$
36,547$ 50,415$ 29,000$ 35,130$
10,964$ 15,124$ 8,700$ 10,539$
47,511$ 65,539$ 37,699$ 45,669$
Fernau Watershed - North Main
Street Area
1Pond retrofit cost for Libbey-Nicolet pond is to construct a retaining wall to allow for construction of equipment building at northeast corner of pond. This area was identified as most feasible building location.
2Pond retrofit cost for Fair-Acres/Murdock pond is to construction a new east inlet pipe and divert it to the west side of pond to create a single inlet.
Based on the design for floc removal currently under consideration, the City will need to purchase a remote dredge to remove the floc from facilities for discharge to the sanitary sewer system. The dredge cost is estimated at $250,000 and can be
used for any and all facilities constructed by the City.
Annual Operation & Maintenance Cost Estimate
Libbey-Nicolet
Construction Sub-Total
Construction Contingency (30%)
Construction Total
Design & CRS (20%)
Annual O&M Contingency (30%)
Total Amount
9th & Washburn
Total Amount
Annual O&M Sub-Total
Item No. Description
9th & Washburn Libbey-Nicolet Fair-Acres
Unit Unit Cost
Item No. Description Unit Unit Cost
Fair-Acres Fernau Watershed - North Main
Street Area
Construction Capital Cost Estimate
Table H-9
Enhanced Phosphorus System Costs
Stormwater Management Plan Update
City of Oshkosh, WI
7/26/2022 Enhanced P Analysis.xlsx
City of Oshkosh Stormwater Quality Management Plan
I-1
Oshkosh SWMP Final.docx
Appendix I: Biofilter / Rain Garden Analysis Additional
Information
Handout 8
Rain Garden/Biofilter Wide-Scale Implementation Summary
# Installed Removal # Installed Removal # Installed Removal # Installed Removal # Installed Removal
Sawyer Creek 628 251 0 628 1 1,256 1 1,884 2 2,512 2
Lake Butte des Morts 120 48 0 120 0 240 0 360 0 480 0
Fox River 1,116 446 0 1,116 1 2,232 2 3,348 3 4,464 4
Lake Winnebago 2,050 820 1 2,050 2 4,100 3 6,150 5 8,200 7
Sawyer Creek 221 22 5 55 12 111 23 166 35 221 46
Lake Butte des Morts 133 13 3 33 7 67 14 100 21 133 28
Fox River 165 17 3 41 9 83 17 124 26 165 35
Lake Winnebago 653 65 14 163 34 327 69 490 103 653 137
Sawyer Creek 181 18 3 45 6 91 13 136 19 181 25
Lake Butte des Morts 296 30 4 74 10 148 21 222 31 296 41
Fox River 306 31 4 77 11 153 21 230 32 306 43
Lake Winnebago 256 26 4 64 9 128 18 192 27 256 36
Sawyer Creek 156 16 2 39 6 78 12 117 18 156 23
Lake Butte des Morts 53 5 1 13 2 27 4 40 6 53 8
Fox River 371 37 6 93 14 186 28 278 42 371 56
Lake Winnebago 344 34 5 86 13 172 26 258 39 344 52
# Installed Removal # Installed Removal # Installed Removal # Installed Removal # Installed Removal
Sawyer Creek 628 251 0 628 1 1,256 1 1,884 2 2,512 2
Lake Butte des Morts 120 48 0 120 0 240 0 360 0 480 0
Fox River 1,116 446 0 1,116 1 2,232 2 3,348 3 4,464 4
Lake Winnebago 2,050 820 1 2,050 2 4,100 3 6,150 5 8,200 7
Sawyer Creek 221 22 5 55 12 111 23 166 35 221 46
Lake Butte des Morts 133 13 3 33 7 67 14 100 21 133 28
Fox River 165 17 3 41 9 83 17 124 26 165 35
Lake Winnebago 653 65 14 163 34 327 69 490 103 653 137
Sawyer Creek 181 18 3 45 6 91 13 136 19 181 25
Lake Butte des Morts 296 30 4 74 10 148 21 222 31 296 41
Fox River 306 31 4 77 11 153 21 230 32 306 43
Lake Winnebago 256 26 4 64 9 128 18 192 27 256 36
Sawyer Creek 156 16 2 39 6 78 12 117 18 156 23
Lake Butte des Morts 53 5 1 13 2 27 4 40 6 53 8
Fox River 371 37 6 93 14 186 28 278 42 371 56
Lake Winnebago 344 34 5 86 13 172 26 258 39 344 52
Biofilter
Construction Cost $32 per sq. ft.
Rain Garden Cost $1,250 each
Reachshed
$20,800 $2,850 $3,509 $25,000
$32,800 $3,500 $4,540 $30,000
$0 $40 $50,000
$25,600 $3,150 $3,962 $19,000
Table I-1
Potential Pollution Reduction of Wide-Scale Rain Garden/Biofilter Implementation
Stormwater Management Plan Update
City of Oshkosh, WI
Land Use
Category
Acres NOT Treated
with Existing
Structural SMPs
TSS Removal per Rain
Garden/ Biofilter
(tons/year)
TSS Control with Variable Treatment Levels (tons/year)Construction Cost
per Rain Garden/
Biofilter
Annualized Cost
per ton of TSS
Removal
10% 25% 50% 75% 100%
TSS Reduction Summary
Reachshed
Annualized cost assumes capital cost is distributed over 100 year life span.
TP Reduction Summary
25%10%
TP Removal per Rain
Garden/ Biofilter
(lbs/year)
Construction Cost
per Rain Garden/
Biofilter
Annualized Cost
per lb of TP
Removal
TP Control with Variable Treatment Levels (lbs/year)
100%75%50%
Annual Maintenance Costs include bi-annual inspections, debris removal and weed control, annual sediment removal, routine mowing of perimeter, annual replacement of 5% of plants and engineered soil, and repair of erosion spots. Includes 30% contingency. Source: Minnesota Storm Water Manual.
Land Use
Category
Acres NOT Treated
with Existing
Structural SMPs
Cost does not include land acquisition or easement. Cost does not include potential site specific items such as pavement removal/restoration, inlet/outlet sewers, or grading to create drainage to biofilter.
Estimated Annual
Maintenance Cost
Total Annualized
Cost
Estimated Annual
Maintenance Cost
Total Annualized
Cost
Source: City of Oshkosh bid results for Lakeshore Park Four-Seasons Building (construction in 2022). Cost includes excavation, engineered soil, stone layer, perforated pipe, geotextile, cleanout, and seeding/plant
plugs. Includes 30% contingency, 15% design/CRS, 10% mobilization costs.
Source: UW-Extension. Cost for private property owner to hire contractor for construction ($10 - $15 per sq. ft.).
Residential
Industrial
Institutional
Commercial
0.001
0.21
0.14
0.15
$1,250
$6,000
Industrial 0.39 $25,600 $3,150 $3,962 $10,000
Residential 0.007 $1,250 $0 $40
$8,000
Commercial 0.36 $32,800 $3,500 $4,540 $13,000
Institutional 0.42 $20,800 $2,850 $3,509
Biofilter Wide Scale Analysis_v2.xlsx 7/19/2022
City of Oshkosh Stormwater Quality Management Plan
J-1
Oshkosh SWMP Final.docx
Appendix J: Redevelopment / New Development
Analysis Supporting Information
Witzel Avenue
Leonard Point Road
Brooks Road
Sand Pit RoadState
R
oad 21
US Highway 45
Lake ButteDes Morts
Wolf River
Source: Future Land Use from the City of Oshkosh 2018
PREPARED SEPTEMBER 2018 BY:
4
0 10.5
Scale in Miles
O:\Tyler\2016\Oshkosh_Comp_Plan\FutureLandUse\FromOshkosh\Quadrants\Future_Land_Use_4_3a.mxd
This data was created for use by the East Central WisconsinRegional Planning Commission Geographic InformationSystem. Any other use/application of this information is theresponsibility of the user and such use/application is at theirown risk. East Central Wisconsin Regional PlanningCommission disclaims all liability regarding fitness of theinformation for any use other than for East CentralWisconsin Regional Planning Commission business.
!Ä Wittman RegionalAirport
Protected Area
Light DensityResidential
Medium and HighDensity Residential
Rural Residential
ConservationResidential
General Commercial
InterstateCommercial
NeighborhoodCommercial
Mixed Use
Industrial
Quarry
Community Facility
Center City
Environmental
Park
Railroad ROW
Water
Map 4-3A: City of Oshkosh Comprehensive Plan Update Year 2040 Future Land Use
F
o
x
RiverEast Central Wisconsin Regional Planning Commission4-21
OhioStreetN Main StreetSnell Road
Vinland StreetJackson StreetIrving Avenue
Murdock Avenue
Indian Point Road
LakeWinnebago
Lake ButteDes Morts
Source: Future Land Use from the City of Oshkosh 2018
PREPARED SEPTEMBER 2018 BY:
4
0 10.5
Scale in Miles
O:\Tyler\2016\Oshkosh_Comp_Plan\FutureLandUse\FromOshkosh\Quadrants\Future_Land_Use_4_3b.mxd
This data was created for use by the East Central WisconsinRegional Planning Commission Geographic InformationSystem. Any other use/application of this information is theresponsibility of the user and such use/application is at theirown risk. East Central Wisconsin Regional PlanningCommission disclaims all liability regarding fitness of theinformation for any use other than for East CentralWisconsin Regional Planning Commission business.
F
o
x
River
Map 4-3B: City of Oshkosh Comprehensive Plan Update Year 2040 Future Land Use
!Ä Wittman RegionalAirport
Protected Area
Light DensityResidential
Medium and HighDensity Residential
Rural Residential
ConservationResidential
General Commercial
InterstateCommercial
NeighborhoodCommercial
Mixed Use
Industrial
Quarry
Community Facility
Center City
Environmental
Park
Railroad ROW
WaterEast Central Wisconsin Regional Planning Commission4-23
Witzel Avenue Oakwood RoadFisk AvenueSand Pit Road9Th St Road
Interstate Highway 4120th Avenue
StateRoad26CountyRoadNStateRoad 44State Road 91
Source: Future Land Use from the City of Oshkosh 2018
PREPARED SEPTEMBER 2018 BY:
4
0 10.5
Scale in Miles
O:\Tyler\2016\Oshkosh_Comp_Plan\FutureLandUse\FromOshkosh\Quadrants\Future_Land_Use_4_3c.mxd
This data was created for use by the East Central WisconsinRegional Planning Commission Geographic InformationSystem. Any other use/application of this information is theresponsibility of the user and such use/application is at theirown risk. East Central Wisconsin Regional PlanningCommission disclaims all liability regarding fitness of theinformation for any use other than for East CentralWisconsin Regional Planning Commission business.
F
o
x
River
Map 4-3C: City of Oshkosh Comprehensive Plan Update Year 2040 Future Land Use
!Ä Wittman RegionalAirport
Protected Area
Light DensityResidential
Medium and HighDensity Residential
Rural Residential
ConservationResidential
General Commercial
InterstateCommercial
NeighborhoodCommercial
Mixed Use
Industrial
Quarry
Community Facility
Center City
Environmental
Park
Railroad ROW
WaterEast Central Wisconsin Regional Planning Commission4-25
!Ä OhioStreetNekimi Avenue
W 18Th Avenue9Th Avenue
Black Wolf AvenueOregonStreetInterstate Highway 41LakeWinnebago
Source: Future Land Use from the City of Oshkosh 2018
PREPARED SEPTEMBER 2018 BY:
4
0 10.5
Scale in Miles
O:\Tyler\2016\Oshkosh_Comp_Plan\FutureLandUse\FromOshkosh\Quadrants\Future_Land_Use_4_3d.mxd
This data was created for use by the East Central WisconsinRegional Planning Commission Geographic InformationSystem. Any other use/application of this information is theresponsibility of the user and such use/application is at theirown risk. East Central Wisconsin Regional PlanningCommission disclaims all liability regarding fitness of theinformation for any use other than for East CentralWisconsin Regional Planning Commission business.
F
o
x
River
Map 4-3D: City of Oshkosh Comprehensive Plan Update Year 2040 Future Land Use
!Ä Wittman RegionalAirport
Protected Area
Light DensityResidential
Medium and HighDensity Residential
Rural Residential
ConservationResidential
General Commercial
InterstateCommercial
NeighborhoodCommercial
Mixed Use
Industrial
Quarry
Community Facility
Center City
Environmental
Park
Railroad ROW
WaterEast Central Wisconsin Regional Planning Commission4-27
Additional
TSS Load
Reduction
(tons/year)
Incremental
TSS
Reduction %
Additional
TSS Load
Reduction
(tons/year)
Incremental
TSS
Reduction %
Additional
TSS Load
Reduction
(tons/year)
Incremental
TSS
Reduction %
Future
Reachshed
TSS
Reduction %
Is TSS Load
Reduction
Target Met?
Sawyer Creek 2,707 354 98 58.4% 27.8% No 727 1.9 2.6 0.3 3.5 1.0% 7.0 2.0% 10.5 3.0% 30.7% No
Lake Butte des Morts 2,137 242 56 20% 23.0% Yes 500 0.1 2.2 0.3 2.6 1.1% 5.1 2.1% 7.7 3.2% 26.3% Yes
Fox River – Lake Butte des Morts
to Lake Winnebago 3,452 557 213 20% 38.3% Yes 694 7.3 1.2 0.5 5.4 1.0% 10.7 1.9% 16.1 2.9% 41.2% Yes
Lake Winnebago 7,041 893 275 20% 30.8% Yes 1,451 4.5 8.7 1.2 11.7 1.3% 23.3 2.6% 35.0 3.9% 34.7% Yes
Totals 15,336 2,045 643 31.6% 3,372 13.7 14.6 2.3 23.1 46.2 69.2
Additional TP
Load
Reduction
(lbs/year)
Incremental
TP Reduction
%
Additional TP
Load
Reduction
(lbs/year)
Incremental
TP Reduction
%
Additional TP
Load
Reduction
(lbs/year)
Incremental
TP Reduction
%
Future
Reachshed
TP Reduction
%
Is TP Load
Reduction
Target Met?
Sawyer Creek 2,707 2,104 425 85.6% 20.2% No 727 1.9 2.6 1.1 10.9 0.5% 21.9 1.0% 32.8 1.6% 21.7% No
Lake Butte des Morts 2,137 1,392 255 85.6% 18.2% No 500 0.1 2.2 0.8 7.7 0.6% 15.4 1.1% 23.1 1.7% 20.0% No
Fox River – Lake Butte des Morts
to Lake Winnebago 3,452 3,023 865 85.6% 28.6% No 694 7.3 1.2 1.7 17.3 0.6% 34.5 1.1% 51.8 1.7% 30.3% No
Lake Winnebago 7,041 5,167 1,282 85.6% 24.8% No 1,451 4.5 8.7 3.4 33.9 0.7% 67.9 1.3% 101.8 2.0% 26.8% No
Totals 15,336 11,685 2,827 24.3% 3,372 13.7 14.6 7.0 69.8 139.7 209.5
Category TSS TP
Redevelopment 40% 27%
Mixed Development 60% 40.5%
New Development 80% 54%
Reachshed
Projected Improvement Under Current Code
10-year Projection
(2022 - 2031)
20-year Projection
(2022 - 2041)
30-year Projection
(2022 - 2051)
Current Conditions
Total
Analyzed
Area (ac)
No Controls
TSS Load
(tons/year)
With-Controls
TSS Load
Reduction
(tons/year)
TMDL Target TSS
Load Reduction
%
With-Controls
TSS Reduction %
(compared to no
controls total
load)
Is TSS Load
Reduction
Target Met?
Redevelopment & Mixed Development Analysis Input Data
Potential
Redevelopment
Area (acres)
Estimated
Annual
Redevelopment
Area (acres)
Estimated
Annual Mixed
Development
Area (acres)
30-year Projection
(2022 - 2051)
Estimated Additional
Annual TSS Load
Reduction from
Redevelopment &
Mixed Development
(tons/year)
Redevelopment & Mixed Development Analysis Input Data Projected Improvement Under Current Code
20-year Projection
(2022 - 2041)Estimated
Annual
Redevelopment
Area (acres)
Potential
Redevelopment
Area (acres)
Current Municipal Code Requirements
Estimated
Annual Mixed
Development
Area (acres)
Estimated Additional
Annual TP Load
Reduction from
Redevelopment &
Mixed Development
(lbs/year)
10-year Projection
(2022 - 2031)
Table J-1. Redevelopment Analysis - Existing Municipal Code Requirements
Total Suspended Solids
Total Phosphorus
Reachshed
Current Conditions
Total
Analyzed
Area (ac)
No Controls
TP Load
(lbs/year)
With-Controls TP
Load Reduction
(lbs/year)
TMDL Target TP
Load Reduction
%
With-Controls TP
Reduction %
(compared to no
controls total
load)
Is TP Load
Reduction
Target Met?
Oshkosh_Redevelopment Analysis_v4.xlsx 9/21/2022
Additional
TSS Load
Reduction
(tons/year)
Incremental
TSS
Reduction %
Additional
TSS Load
Reduction
(tons/year)
Incremental
TSS
Reduction %
Additional
TSS Load
Reduction
(tons/year)
Incremental
TSS
Reduction %
Future
Reachshed
TSS
Reduction %
Is TSS Load
Reduction
Target Met?
Sawyer Creek 2,707 354 98 58.4% 27.8% No 727 1.9 2.6 0.5 4.8 1.3% 9.5 2.7% 14.3 4.0% 31.8% No
Lake Butte des Morts 2,137 242 56 20% 23.0% Yes 500 0.1 2.2 0.3 3.1 1.3% 6.2 2.6% 9.3 3.8% 27.0% Yes
Fox River – Lake Butte des Morts
to Lake Winnebago 3,452 557 213 20% 38.3% Yes 694 7.3 1.2 0.8 8.2 1.5% 16.4 2.9% 24.5 4.4% 42.7% Yes
Lake Winnebago 7,041 893 275 20% 30.8% Yes 1,451 4.5 8.7 1.5 15.2 1.7% 30.4 3.4% 45.6 5.1% 35.9% Yes
Totals 15,336 2,045 643 31.6% 3,372 13.7 14.6 3.1 31.2 62.5 93.7
Additional TP
Load
Reduction
(lbs/year)
Incremental
TP Reduction
%
Additional TP
Load
Reduction
(lbs/year)
Incremental
TP Reduction
%
Additional TP
Load
Reduction
(lbs/year)
Incremental
TP Reduction
%
Future
Reachshed
TP Reduction
%
Is TP Load
Reduction
Target Met?
Sawyer Creek 2,707 2,104 425 85.6% 20.2% No 727 1.9 2.6 1.5 14.9 0.7% 29.8 1.4% 44.7 2.1% 22.3% No
Lake Butte des Morts 2,137 1,392 255 85.6% 18.2% No 500 0.1 2.2 0.9 9.3 0.7% 18.7 1.3% 28.0 2.0% 20.3% No
Fox River – Lake Butte des Morts
to Lake Winnebago 3,452 3,023 865 85.6% 28.6% No 694 7.3 1.2 2.6 26.3 0.9% 52.5 1.7% 78.8 2.6% 31.2% No
Lake Winnebago 7,041 5,167 1,282 85.6% 24.8% No 1,451 4.5 8.7 4.4 44.1 0.9% 88.1 1.7% 132.2 2.6% 27.4% No
Totals 15,336 11,685 2,827 24.3% 3,372 13.7 14.6 9.5 94.6 189.2 283.7
Category TSS TP
Redevelopment 58% 39%
Mixed Development 72% 48.4%
New Development 85% 57%
Estimated
Annual Mixed
Development
Area (acres)
Estimated Additional
Annual TP Load
Reduction from
Redevelopment &
Mixed Development
(lbs/year)
Scenario #1 Municipal Code Requirements
With-Controls TP
Load Reduction
(lbs/year)
TMDL Target TP
Load Reduction
%
With-Controls TP
Reduction %
(compared to no
controls total
load)
Is TP Load
Reduction
Target Met?
Estimated
Annual
Redevelopment
Area (acres)
Estimated
Annual Mixed
Development
Area (acres)
Estimated Additional
Annual TSS Load
Reduction from
Redevelopment &
Mixed Development
(tons/year)
10-year Projection
(2022 - 2031)
20-year Projection
(2022 - 2041)Estimated
Annual
Redevelopment
Area (acres)
Total Phosphorus
Reachshed
Current Conditions Redevelopment & Mixed Development Analysis Input Data Projected Improvement Under Scenario #1
Total
Analyzed
Area (ac)
No Controls
TP Load
(lbs/year)
30-year Projection
(2022 - 2051)
Potential
Redevelopment
Area (acres)
Table J-2. Redevelopment Analysis - Municipal Code Change Scenario #1
Total Suspended Solids
Reachshed
Current Conditions Redevelopment & Mixed Development Analysis Input Data Projected Improvement Under Scenario #1
Total
Analyzed
Area (ac)
No Controls
TSS Load
(tons/year)
With-Controls
TSS Load
Reduction
(tons/year)
TMDL Target TSS
Load Reduction
%
10-year Projection
(2022 - 2031)
20-year Projection
(2022 - 2041)
30-year Projection
(2022 - 2051)With-Controls
TSS Reduction %
(compared to no
controls total
load)
Is TSS Load
Reduction
Target Met?
Potential
Redevelopment
Area (acres)
Oshkosh_Redevelopment Analysis_v4.xlsx 9/21/2022
Additional
TSS Load
Reduction
(tons/year)
Incremental
TSS
Reduction %
Additional
TSS Load
Reduction
(tons/year)
Incremental
TSS
Reduction %
Additional
TSS Load
Reduction
(tons/year)
Incremental
TSS
Reduction %
Future
Reachshed
TSS
Reduction %
Is TSS Load
Reduction
Target Met?
Sawyer Creek 2,707 354 98 58.4% 27.8% No 727 1.9 2.6 0.4 4.5 1.3% 9.0 2.5% 13.4 3.8% 31.6% No
Lake Butte des Morts 2,137 242 56 20% 23.0% Yes 500 0.1 2.2 0.3 3.1 1.3% 6.1 2.5% 9.2 3.8% 27.0% Yes
Fox River – Lake Butte des Morts
to Lake Winnebago 3,452 557 213 20% 38.3% Yes 694 7.3 1.2 0.7 7.3 1.3% 14.5 2.6% 21.8 3.9% 42.2% Yes
Lake Winnebago 7,041 893 275 20% 30.8% Yes 1,451 4.5 8.7 1.5 14.5 1.6% 29.0 3.3% 43.5 4.9% 35.7% Yes
Totals 15,336 2,045 643 31.6% 3,372 13.7 14.6 2.9 29.3 58.6 87.9
Additional TP
Load
Reduction
(lbs/year)
Incremental
TP Reduction
%
Additional TP
Load
Reduction
(lbs/year)
Incremental
TP Reduction
%
Additional TP
Load
Reduction
(lbs/year)
Incremental
TP Reduction
%
Future
Reachshed
TP Reduction
%
Is TP Load
Reduction
Target Met?
Sawyer Creek 2,707 2,104 425 85.6% 20.2% No 727 1.9 2.6 1.4 14.0 0.7% 28.1 1.3% 42.1 2.0% 22.2% No
Lake Butte des Morts 2,137 1,392 255 85.6% 18.2% No 500 0.1 2.2 0.9 9.2 0.7% 18.4 1.3% 27.6 2.0% 20.3% No
Fox River – Lake Butte des Morts
to Lake Winnebago 3,452 3,023 865 85.6% 28.6% No 694 7.3 1.2 2.3 23.3 0.8% 46.6 1.5% 69.9 2.3% 30.9% No
Lake Winnebago 7,041 5,167 1,282 85.6% 24.8% No 1,451 4.5 8.7 4.2 42.1 0.8% 84.2 1.6% 126.2 2.4% 27.3% No
Totals 15,336 11,685 2,827 24.3% 3,372 13.7 14.6 8.9 88.6 177.2 265.8
Category TSS TP
Redevelopment 52% 35%
Mixed Development 71% 47.9%
New Development 90% 61%
Estimated
Annual Mixed
Development
Area (acres)
Estimated Additional
Annual TP Load
Reduction from
Redevelopment &
Mixed Development
(lbs/year)
Scenario #2 Municipal Code Requirements
With-Controls TP
Load Reduction
(lbs/year)
TMDL Target TP
Load Reduction
%
With-Controls TP
Reduction %
(compared to no
controls total
load)
Is TP Load
Reduction
Target Met?
Estimated
Annual
Redevelopment
Area (acres)
Estimated
Annual Mixed
Development
Area (acres)
Estimated Additional
Annual TSS Load
Reduction from
Redevelopment &
Mixed Development
(tons/year)
10-year Projection
(2022 - 2031)
20-year Projection
(2022 - 2041)Estimated
Annual
Redevelopment
Area (acres)
Total Phosphorus
Reachshed
Current Conditions Redevelopment & Mixed Development Analysis Input Data Projected Improvement Under Scenario #2
Total
Analyzed
Area (ac)
No Controls
TP Load
(lbs/year)
30-year Projection
(2022 - 2051)
Potential
Redevelopment
Area (acres)
Table J-3. Redevelopment Analysis - Municipal Code Change Scenario #2
Total Suspended Solids
Reachshed
Current Conditions Redevelopment & Mixed Development Analysis Input Data Projected Improvement Under Scenario #2
Total
Analyzed
Area (ac)
No Controls
TSS Load
(tons/year)
With-Controls
TSS Load
Reduction
(tons/year)
TMDL Target TSS
Load Reduction
%
10-year Projection
(2022 - 2031)
20-year Projection
(2022 - 2041)
30-year Projection
(2022 - 2051)With-Controls
TSS Reduction %
(compared to no
controls total
load)
Is TSS Load
Reduction
Target Met?
Potential
Redevelopment
Area (acres)
Oshkosh_Redevelopment Analysis_v4.xlsx 9/21/2022
acres % of Total acres % of Total acres % of Total acres % of Total
Sawyer Creek 2,683 17.5% 495 25.2% 2,166 30.6% 2,661 29.4%
Lake Butte des Morts 2,136 13.9% 692 35.2% 2,655 37.5% 3,348 37.0%
Fox River 3,451 22.5% 34 1.7% 185 2.6% 219 2.4%
Lake Winnebago 7,041 45.9% 748 38.0% 1,854 26.2% 2,601 28.8%
Neenah Slough 35 0.2% 0 0.0% 216 3.1% 216 2.4%
Total 15,346 1,969 7,076 9,045
2014 SWMP Analyzed Area 14,648 acres
2022 SWMP Analyzed Area 15,371 acres
Increased in Analyzed Area 723 acres
Years between Plans 7 years
Average Analyzed Area Growth Rate 103.3 acres/year
Land Use 2015 2020 2025 2030 2035 2040
Total
Increase
Average
Annual
Increase
Commercial 1,623 1,714 1,805 1,897 1,988 2,078 455 18.2
Industrial 1,045 1,103 1,162 1,221 1,279 1,337 292 11.7
Residential, Multi-Family 774 804 834 864 894 923 149 6.0
Residential, Single Family 3,922 4,073 4,225 4,377 4,529 4,681 759 30.4
Total 7,364 7,694 8,026 8,359 8,690 9,019 1,655 66.2
Land Use 2015 2020 2025 2030 2035 2040
Total
Increase
Average
Annual
Increase
Commercial 1,623 1,732 1,842 1,951 2,060 2,169 546 21.8
Industrial 1,045 1,115 1,185 1,256 1,326 1,396 351 14.0
Residential, Multi-Family 738 812 850 888 926 964 226 9.0
Residential, Single Family 3,922 4,114 4,307 4,500 4,692 4,885 963 38.5
Total 7,328 7,773 8,184 8,595 9,004 9,414 2,086 83.4
Projected Growth Rate for Planning
Analysis 80
Table J-4. New Development Analysis - Projected Growth
Note: Area as of December 2013
Note: Area as of December 2020
Change in Analyzed Area Since 2014 SWMP
Reachshed
Current Conditions
Analyzed Area
Undeveloped Area inside
City Limits
Undeveloped Area in
2040 Planning Area Total Undeveloped Area
Assume new development occurs based on the percentage of total undeveloped area that is available within each reachshed (i.e. 29.4% of development occurs
within Sawyer Creek reachshed)
At current development rate there is approximately 25 years of developable land within the City limits. There is development that occurs outside of the current
city limits on an annual basis. Assume the area inside of the City limits develops evenly over the 30-year planning period for this project. Annual New
Development within city limits = 65.6 acres. Annual New Development outside city limits = 14.4 acres.
Additional Analysis Notes
Projected Growth as per City of Oshkosh Comprehensive Plan Update 2040
Projected Growth as per City of Oshkosh Comprehensive Plan Update 2040
Future Land Use Consumption in Acres - Scenario #1, Low Estimate (Table 4-7 of Plan)
Future Land Use Consumption in Acres - Scenario #2, High Estimate (Table 4-8 of Plan)
acres/year
Comprehensive plan projections do not include right-of-way area in consumption area.
Growth rate used for analysis selected based on change in analyzed area since last SWMP and comprehensive plan.
New Development Analysis Spreadsheet Working_v3.xlsx 7/28/2022
acres % of Total acres % acres % acres % acres % acres % acres %acres %
TSS
(tons/ac/yr)
TP
(lbs/ac/yr)
Sawyer Creek 2,661 29.4% 0 0.0% 1,112 41.8% 81 3.1% 20 0.7% 5 0.2% 427 16.0% 1,016 38.2% 0.18 0.87
Lake Butte des Morts 3,348 37.0% 685 20.5% 1,852 55.3% 278 8.3% 34 1.0% 269 8.0% 131 3.9% 99 3.0% 0.12 0.79
Fox River 219 2.4% 118 54.0% 3 1.3% 0 0.0% 0 0.1% 0 0.2% 76 34.7%21 9.8% 0.13 0.79
Lake Winnebago 2,601 28.8% 221 8.5% 1,178 45.3% 75 2.9% 31 1.2% 246 9.5% 299 11.5% 552 21.2% 0.15 0.83
Neenah Slough 216 2.4% 0 0.0% 98 45.5% 110 51.0% 0 0.0% 8 3.5% 0 0.0% 0 0.0% 0.12 0.85
Total 9,045 1,024 11.3% 4,242 46.9% 544 6.0% 86 0.9% 528 5.8% 933 10.3% 1,688 18.7% 0.15 0.83
Mixed land Use is assumed to be 50% MFRNA, 25% SCOM, and 25% OFPK
0.14
0.89
0.25
1.07
0.19
0.82
TSS (tons/ac/yr)
TP (tons/ac/yr)
0.08
0.67
0.10
0.80 0.91
0.18
0.93
Pollutant Unit Load LDR MDRNA MFRNA SCOM
Corresponding WinSLAMM SLU File for Future Land Use Categories
0.26
SHOP MIXED LI
Table J-5. New Development Analysis - Projected Land Use
Reachshed
Area of Future Land Use Categories for Undeveloped Areas by Reachshed
Conservation
Residential
Light Density
Residential
Total Undeveloped
Area
Average Development Unit
Load by ReachshedMedium/High
Density Residential
General or
Neighborhood
Interstate
Commercial Mixed Use Industrial
New Development Analysis Spreadsheet Working_v3.xlsx 7/28/2022
Estimated
Annual New
Development
Area
Existing
OSUD in
Analyzed
Area
Estimated
Annual
Development
Rate of OSUD
TSS
(tons/ac/yr)
TP
(lbs/ac/yr)acres acres acres
TSS
(tons/yr)
TP
(lbs/yr)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
(tons/yr)
TP
(lbs/yr)
Sawyer Creek 0.18 0.87 24 170 5.7 0.1 1.7 4.2 20.4 3.3 11.0 3.6 11.7 3.8 12.4
Lake Butte des Morts 0.12 0.79 30 279 9.3 0.2 2.8 3.5 23.4 2.8 12.7 3.0 13.5 3.1 14.2
Fox River 0.13 0.79 2 27 0.9 0.0 0.3 0.3 1.5 0.2 0.8 0.2 0.9 0.2 0.9
Lake Winnebago 0.15 0.83 23 295 9.8 0.2 2.9 3.6 19.2 2.8 10.4 3.0 11.0 3.2 11.6
Neenah Slough 0.12 0.85 2 0 0.0 0.0 0.0 0.2 1.6 0.2 0.9 0.2 0.9 0.2 1.0
Total 0.15 0.83 80 771 26 1 8 11.7 66.1 9.4 35.7 10.0 37.9 10.6 40.2
TSS TP TSS TP TSS TP
80% 54% 85% 57% 90% 61%New Development
Current Requirements Scenario #1
Requirements
Scenario #2
Requirements
New Development Municipal Code Requirements
Category
Existing Annual Load
from OSUD that is
Developed
Table J-6. New Development Analysis - Projected Load Reductions Under Municipal Code Scenarios
Scenario #1
Ordinance Annual
New Development
Load Reduction
Scenario #2
Ordinance Annual
New Development
Load Reduction
Current Ordinance
Annual New
Development Load
ReductionReachshed
Annual New
Development Base
Load
Average Development Unit
Load for by Reachshed
New Development Analysis Spreadsheet Working_v3.xlsx 7/28/2022
Existing
OSUD in
Analyzed
Area
Projected
Analyzed
Area
Projected
TSS Base
Load
Projected
With Controls
TSS Load
Reduction
Projected
Analyzed
Area
Projected
TSS Base
Load
Projected
With Controls
TSS Load
Reduction
Projected
Analyzed
Area
Projected
TSS Base
Load
Projected
With Controls
TSS Load
Reduction
(acres) (acres) (acres) (tons/year) (tons/year) (acres) (tons/year) (tons/year) (acres) (tons/year) (tons/year)
Sawyer Creek 2,707 351 98 58.4% 27.8% No 170 24 2,942 391 132 33.7% 3,178 431 165 38.3% 3,413 472 199 42.1% 14.3% No
Lake Butte des Morts 2,137 242 56 20% 23.2% Yes 279 30 2,433 275 84 30.6% 2,729 307 112 36.4% 3,025 340 140 41.2% 18.0% Yes
Fox River 3,452 557 213 20% 38.3% Yes 27 2 3,471 559 215 38.5% 3,491 561 217 38.7% 3,510 564 219 38.9% 0.6% Yes
Lake Winnebago 7,041 893 275 20% 30.8% Yes 295 23 7,271 926 304 32.8% 7,501 959 332 34.6% 7,731 992 360 36.3% 5.5% Yes
Neenah Slough 35 2 0 52% 0% No 0 2 54 5 2 41.8% 73 7 4 54.9% 92 9 6 61.3% 61.3% Yes
Total 15,371 2,044 643 771 80 16,171 2,155 736 16,971 2,266 830 17,771 2,377 924
Existing
OSUD in
Analyzed
Area
Projected
Analyzed
Area
Projected TP
Base Load
Projected
With Controls
TP Load
Reduction
Projected
Analyzed
Area
Projected TP
Base Load
Projected
With Controls
TP Load
Reduction
Projected
Analyzed
Area
Projected TP
Base Load
Projected
With Controls
TP Load
Reduction
(acres) (acres) (acres) (lbs/year) (lbs/year) (acres) (lbs/year) (lbs/year) (acres) (lbs/year) (lbs/year)
Sawyer Creek 2,707 2,081 425 85.6% 20.6% No 170 24 2,942 2,268 535 23.6% 3,178 2,455 645 26.3% 3,413 2,642 755 28.6% 8.0% No
Lake Butte des Morts 2,137 1,391 255 85.6% 18.2% No 279 30 2,433 1,598 381 23.9% 2,729 1,805 508 28.1% 3,025 2,011 635 31.5% 13.3% No
Fox River 3,452 3,021 865 85.6% 28.6% No 27 2 3,471 3,034 873 28.8% 3,491 3,047 882 28.9% 3,510 3,059 890 29.1% 0.5% No
Lake Winnebago 7,041 5,167 1,282 85.6% 24.8% No 295 23 7,271 5,330 1,386 26.0% 7,501 5,492 1,489 27.1% 7,731 5,654 1,593 28.2% 3.4% No
Neenah Slough 35 20 0 40.5% 0.0% No 0 2 54 36 9 24.5% 73 52 17 33.7% 92 68 26 38.5% 38.5% No
Total 15,371 11,681 2,827 771 80 16,171 12,265 3,184 16,971 12,850 3,541 17,771 13,435 3,898
Projected
Annual New
Development
Rate
10-year Projection (2022 - 2031) 20-year Projection (2022 - 2041) 30-year Projection (2022 - 2051)
Projected
With Controls
TP Load
Reduction %
Projected
With Controls
TP Load
Reduction %
Projected
With Controls
TP Load
Reduction %
Projected
Change in TP
Load
Reduction %
Is TP Load
Reduction
Target Met
Reachshed
Total
Analyzed
Area (ac)
No Controls
TSS Load
(tons/year)
With-Controls
TSS Load
Reduction
(tons/year)
TMDL Target
TSS Load
Reduction %
Reachshed
Current Conditions
Is TSS Load
Reduction
Target Met?
With-Controls
TSS Reduction %
(compared to no
controls total
load)
Current Conditions
Total
Analyzed
Area (ac)
No Controls
TP Load
(lbs/year)
With-Controls
TP Load
Reduction
(lbs/year)
TMDL Target
TP Load
Reduction %
With-Controls TP
Reduction %
(compared to no
controls total
load)
Is TP Load
Reduction
Target Met?
Table J-7. New Development Analysis - Reachshed Impacts Under Existing Municipal Code Requirements
Total Suspended Solids
Total Phosphorus
Projected
With Controls
TSS Load
Reduction %
Projected
With Controls
TSS Load
Reduction %
Projected
With Controls
TSS Load
Reduction %
Projected
Change in TSS
Load
Reduction %
Is TSS Load
Reduction
Target Met
10-year Projection (2022 - 2031) 20-year Projection (2022 - 2041) 30-year Projection (2022 - 2051)
Projected
Annual New
Development
Rate
New Development Analysis Spreadsheet Working_v4.xlsx 9/22/2022
Existing
OSUD in
Analyzed
Area
Projected
Analyzed
Area
Projected
TSS Base
Load
Projected
With Controls
TSS Load
Reduction
Projected
Analyzed
Area
Projected
TSS Base
Load
Projected
With Controls
TSS Load
Reduction
Projected
Analyzed
Area
Projected
TSS Base
Load
Projected
With Controls
TSS Load
Reduction
(acres) (acres) (acres) (tons/year) (tons/year) (acres) (tons/year) (tons/year) (acres) (tons/year) (tons/year)
Sawyer Creek 2,707 351 98 58.4% 27.8% No 170 24 2,942 391 134 34.2% 3,178 431 169 39.3% 3,413 472 205 43.4% 15.6% No
Lake Butte des Morts 2,137 242 56 20% 23.2% Yes 279 30 2,433 275 86 31.2% 2,729 307 115 37.6% 3,025 340 145 42.7% 19.5% Yes
Fox River 3,452 557 213 20% 38.3% Yes 27 2 3,471 559 215 38.5% 3,491 561 217 38.7% 3,510 564 220 39.0% 0.7% Yes
Lake Winnebago 7,041 893 275 20% 30.8% Yes 295 23 7,271 926 305 33.0% 7,501 959 336 35.0% 7,731 992 366 36.9% 6.1% Yes
Neenah Slough 35 2 0 52% 0% No 0 2 54 5 2 44.4% 73 7 4 58.3% 92 9 6 65.2% 65.2% Yes
Total 15,371 2,044 643 771 80 16,171 2,155 742 16,971 2,266 842 17,771 2,377 941
Existing
OSUD in
Analyzed
Area
Projected
Analyzed
Area
Projected TP
Base Load
Projected
With Controls
TP Load
Reduction
Projected
Analyzed
Area
Projected TP
Base Load
Projected
With Controls
TP Load
Reduction
Projected
Analyzed
Area
Projected TP
Base Load
Projected
With Controls
TP Load
Reduction
(acres) (acres) (acres) (lbs/year) (lbs/year) (acres) (lbs/year) (lbs/year) (acres) (lbs/year) (lbs/year)
Sawyer Creek 2,707 2,081 425 85.6% 20.2% No 170 24 2,942 2,268 542 23.9% 3,178 2,455 658 26.8% 3,413 2,642 775 29.4% 9.2% No
Lake Butte des Morts 2,137 1,391 255 85.6% 18.3% No 279 30 2,433 1,598 389 24.4% 2,729 1,805 524 29.0% 3,025 2,011 658 32.7% 14.4% No
Fox River 3,452 3,021 865 85.6% 28.6% No 27 2 3,471 3,034 874 28.8% 3,491 3,047 883 29.0% 3,510 3,059 891 29.1% 0.5% No
Lake Winnebago 7,041 5,167 1,282 85.6% 24.8% No 295 23 7,271 5,330 1,392 26.1% 7,501 5,492 1,502 27.4% 7,731 5,654 1,612 28.5% 3.7% No
Neenah Slough 35 20 0 40.5% 0.0% No 0 2 54 36 9 26.0% 73 52 19 35.8% 92 68 28 40.9% 40.9% Yes
Total 15,371 11,681 2,827 771 80 16,171 12,265 3,206 16,971 12,850 3,586 17,771 13,435 3,965
Projected
With Controls
TP Load
Reduction %
Projected
With Controls
TP Load
Reduction %
Projected
With Controls
TP Load
Reduction %
Projected
Change in TP
Load
Reduction %
Is TP Load
Reduction
Target Met
Total
Analyzed
Area (ac)
No Controls
TP Load
(lbs/year)
With-
Controls TP
Load
Reduction
(lbs/year)
TMDL Target
TP Load
Reduction %
With-Controls TP
Reduction %
(compared to no
controls total
load)
Is TP Load
Reduction
Target Met?
Projected
With Controls
TSS Load
Reduction %
Projected
Change in TSS
Load
Reduction %
Is TSS Load
Reduction
Target Met
Total Phosphorus
Reachshed
Current Conditions
Projected
Annual New
Development
Rate
10-year Projection (2022 - 2031) 20-year Projection (2022 - 2041) 30-year Projection (2022 - 2051)
With-
Controls TSS
Load
Reduction
(tons/year)
TMDL Target
TSS Load
Reduction %
With-Controls
TSS Reduction %
(compared to no
controls total
load)
Is TSS Load
Reduction
Target Met?
Projected
With Controls
TSS Load
Reduction %
Projected
With Controls
TSS Load
Reduction %
Table J-8. New Development Analysis - Reachshed Impacts Under Municipal Code Change Scenario #1
Total Suspended Solids
Reachshed
Current Conditions
Projected
Annual New
Development
Rate
10-year Projection (2022 - 2031) 20-year Projection (2022 - 2041) 30-year Projection (2022 - 2051)
Total
Analyzed
Area (ac)
No Controls
TSS Load
(tons/year)
New Development Analysis Spreadsheet Working_v4.xlsx 9/22/2022
Existing
OSUD in
Analyzed
Area
Projected
Analyzed
Area
Projected
TSS Base
Load
Projected
With Controls
TSS Load
Reduction
Projected
Analyzed
Area
Projected
TSS Base
Load
Projected
With Controls
TSS Load
Reduction
Projected
Analyzed
Area
Projected
TSS Base
Load
Projected
With Controls
TSS Load
Reduction
(acres) (acres) (acres) (tons/year) (tons/year) (acres) (tons/year) (tons/year) (acres) (tons/year) (tons/year)
Sawyer Creek 2,707 351 98 58.4% 27.8% No 170 24 2,942 391 136 34.8% 3,178 431 174 40.2% 3,413 472 211 44.8% 17.0% No
Lake Butte des Morts 2,137 242 56 20% 23.2% Yes 279 30 2,433 275 88 31.9% 2,729 307 119 38.7% 3,025 340 150 44.2% 21.1% Yes
Fox River 3,452 557 213 20% 38.3% Yes 27 2 3,471 559 215 38.5% 3,491 561 218 38.8% 3,510 564 220 39.0% 0.8% Yes
Lake Winnebago 7,041 893 275 20% 30.8% Yes 295 23 7,271 926 307 33.2% 7,501 959 339 35.4% 7,731 992 371 37.4% 6.6% Yes
Neenah Slough 35 2 0 52% 0% No 0 2 54 5 2 47.0% 73 7 4 61.8% 92 9 6 69.0% 69.0% Yes
Total 15,371 2,044 643 771 80 16,171 2,155 748 16,971 2,266 854 17,771 2,377 959
Existing
OSUD in
Analyzed
Area
Projected
Analyzed
Area
Projected TP
Base Load
Projected
With Controls
TP Load
Reduction
Projected
Analyzed
Area
Projected TP
Base Load
Projected
With Controls
TP Load
Reduction
Projected
Analyzed
Area
Projected TP
Base Load
Projected
With Controls
TP Load
Reduction
(acres) (acres) (acres) (lbs/year) (lbs/year) (acres) (lbs/year) (lbs/year) (acres) (lbs/year) (lbs/year)
Sawyer Creek 2,707 2,081 425 85.6% 20.2% No 170 24 2,942 2,268 548 24.2% 3,178 2,455 672 27.4% 3,413 2,642 796 30.1% 9.9% No
Lake Butte des Morts 2,137 1,391 255 85.6% 18.3% No 279 30 2,433 1,598 397 24.9% 2,729 1,805 540 29.9% 3,025 2,011 682 33.9% 15.6% No
Fox River 3,452 3,021 865 85.6% 28.6% No 27 2 3,471 3,034 874 28.8% 3,491 3,047 884 29.0% 3,510 3,059 893 29.2% 0.6% No
Lake Winnebago 7,041 5,167 1,282 85.6% 24.8% No 295 23 7,271 5,330 1,399 26.2% 7,501 5,492 1,515 27.6% 7,731 5,654 1,632 28.9% 4.0% No
Neenah Slough 35 20 0 40.5% 0.0% No 0 2 54 36 10 27.5% 73 52 20 37.9% 92 68 29 43.3% 43.3% Yes
Total 15,371 11,681 2,827 771 80 16,171 12,265 3,229 16,971 12,850 3,630 17,771 13,435 4,032
Projected
With Controls
TP Load
Reduction %
Projected
With Controls
TP Load
Reduction %
Projected
With Controls
TP Load
Reduction %
Projected
Change in TP
Load
Reduction %
Is TP Load
Reduction
Target Met
Total
Analyzed
Area (ac)
No Controls
TP Load
(lbs/year)
With-Controls
TP Load
Reduction
(lbs/year)
TMDL Target
TP Load
Reduction %
With-Controls TP
Reduction %
(compared to no
controls total
load)
Is TP Load
Reduction
Target Met?
Projected
With Controls
TSS Load
Reduction %
Projected
Change in TSS
Load
Reduction %
Is TSS Load
Reduction
Target Met
Total Phosphorus
Reachshed
Current Conditions
Projected
Annual New
Development
Rate
10-year Projection (2022 - 2031) 20-year Projection (2022 - 2041) 30-year Projection (2022 - 2051)
With-Controls
TSS Load
Reduction
(tons/year)
TMDL Target
TSS Load
Reduction %
With-Controls
TSS Reduction %
(compared to no
controls total
load)
Is TSS Load
Reduction
Target Met?
Projected
With Controls
TSS Load
Reduction %
Projected
With Controls
TSS Load
Reduction %
Table J-9. New Development Analysis - Reachshed Impacts Under Municipal Code Change Scenario #2
Total Suspended Solids
Reachshed
Current Conditions
Projected
Annual New
Development
Rate
10-year Projection (2022 - 2031) 20-year Projection (2022 - 2041) 30-year Projection (2022 - 2051)
Total
Analyzed
Area (ac)
No Controls
TSS Load
(tons/year)
New Development Analysis Spreadsheet Working_v4.xlsx 9/22/2022
City of Oshkosh Stormwater Quality Management Plan
K-1
Oshkosh SWMP Final.docx
Appendix K: Implementation Plan
TSS TP TSS TP TSS TP TSS TP TSS TP TSS TP TSS TP TSS TP TSS TP TSS TP
(tons/yr)(lbs/yr)(%)(%)(tons/yr)(lbs/yr)(%)(%)(tons/yr)(lbs/yr)(%)(%)(tons/yr)(lbs/yr)(%)(%)(tons/yr)(lbs/yr)(%)(%)
No Controls Load
(per 2022 Citywide SWMP)354 2104 242 1392 557 3023 893 5167 2 20
TMDL Reduction Targets 207 1801 58.4% 85.6% 48 1192 20.0% 85.6% 111 2588 20.0% 85.6% 179 4423 20.0% 85.6% 1 8 52.0% 40.5%
With Controls Current Load Reductions
(per 2022 Citywide SWMP)98 425 27.8% 20.2% 56 255 23.2% 18.3% 213 865 38.3% 28.6% 275 1282 30.8% 24.8% 0 0 0.0% 0.0%
With Controls Remaining Load 256 1679 186 1137 344 2158 618 3885 2 20
Are TMDL Reduction Requirements
Achieved?NO NO YES NO YES NO YES NO NO NO
NR 151 Required Reduction
(TSS = 20%, TP = 15%)71 316 20.0% 15.0% 48 209 20.0% 15.0% 111 453 20.0% 15.0% 179 775 20.0% 15.0% 0 3 20.0% 15.0%
NR 151 Allowable Load
(TMDL Baseline load)283 1788 194 1183 445 2570 714 4392 2 17
Allowable TMDL Wasteload 147 303 194 200 445 435 714 744 1 12
Additional Reduction from NR 151 Needed 136 1485 0 983 0 2134 0 3648 1 5
Additional Reduction Needed for Next
Permit Term (TSS = 20%, TP = 10%)27 149 0 98 0 213 0 365 0 1
Total Reduction Needed @ End of Next
Permit Term (2029)98 464 27.7% 22.1% 48 307 20.0% 22.1% 111 667 20.0% 22.1% 179 1140 20.0% 22.1% 1 4 26.4% 17.6%
Is Next Permit Term Reduction
Requirement Achieved?YES NO YES NO YES YES YES YES NO NO
Added Reduction Needed in Next Permit
Term 0 39 -8 52 -102 -198 -96 -142 1 4
Cumulative TSS Reduction Required in
Next Permit Term -206
Cumulative TP Reduction Required in Next
Permit Term -246
Negative value = Excess reduction
(Sum of reduction from all
reachsheds)
Table K-1
Existing Conditions & 2024-2029 WPDES Permit Compliance Summary
Stormwater Management Plan Update
City of Oshkosh, WI
2024-2029 Permit Summary - Citywide
Neenah Slough
TMDL Compliance SummaryCalculations for Compliance with Reductions for 2024-2029 Permit (MS4 Permit Section c.4.3 b.)Sawyer Creek Lake Butte des Morts Fox River Lake Winnebago
Oshkosh TMDL Implementation Plan Summary_v3.xlsx 9/21/2022
$ Rank $ Rank
Lake Butte
des Morts
Washburn St / Westowne Ave Wet
Pond Retrofit (SMP 6)1.9 0.1 0.8% 0.0% $7,000 $295,100 $21,461 $11,295 12 $214,606 23 1 2024-2029
City has completed initial project design and is in land acquisition process. Project is believed to
be close to "shovel-ready." TP reduction may be increased by phosphorus reduction cell
included in preliminary design. Reductions from cell not currently accounted for due to lack of
guidance.
Sawyer Creek Pheasant Creek Dry Pond Retrofit
(SMP 7)3.3 18.0 0.9% 0.9% $48,000 $935,100 $50,967 $15,444 15 $2,831 12 6 2049-2054
Site is located in Sawyer Creek reachshed and is a cost-effective step towards TMDL
requirements, particularly if street reconstruction costs for 9th Ave diversion sewer are avoided.
Project is scheduled for approximate time-frame when street reconstruction could occur.
Diversion could be delayed and implemented at a later date to coincide with street
reconstruction if needed. Drainage area includes substantial undeveloped land upstream in
watershed - new development and incorporation of those SMPs could impact performance.
Scheduled implementation time-frame should allow for understanding of development impacts
Lake
Winnebago
Island View Estates Dry Pond
Retrofit (SMP 15)2.2 13.0 0.2% 0.3% $43,000 $724,200 $52,780 $23,991 17 $4,060 16 Future Unknown
Sawyer Creek Miles Kimball North Dry Pond
Retrofit (SMP 16B)3.6 9.1 1.0% 0.4% $46,000 $375,800 $25,116 $6,977 5 $2,760 11 N/A N/A
Site is located upstream of Fox Tail Lane New Wet Basin. Fox Tail Lane is a more preferred and
cost-effective site and higher priority for implementation. Site may be reconsidered in future if
Fox Tail Lane site can't be implemented.
Sawyer Creek Miles Kimball South Dry Pond
Retrofit (SMP 16A)2.2 5.6 0.6% 0.3% $41,000 $440,800 $23,049 $10,976 11 $4,191 17 Future Unknown
Lake
Winnebago
Bowen Street New Wet Pond (SMP
26)12.8 52.5 1.4% 1.0% $1,462,000 $941,000 $87,997 $6,875 4 $1,676 8 Future Unknown
Sawyer Creek Oakwood & 20th New Wet Pond
(SMP 29A)9.4 25.7 2.7% 1.2% $1,465,000 $941,000 $92,524 $9,843 10 $3,600 15 2 2029-2034
Alternative to Fox Tail Lane Site. Located upstream of Fox Tail Lane New Wet Basin. Fox Tail Lane
is preferred location to provide treatment for entire drainage area. If Fox Tail Lane can't be
implemented may consider this site as an alternative location. Both project to be evaluated as
part of planning for Fox Tail Lane to determine optimum location and treatment ability. If this site
will also be implemented it may scheduled for subsequent time periods.
Sawyer Creek Fox Tail Lane New Wet Pond (SMP
29B)15.0 55.6 4.2% 2.6% $0 $1,035,700 $53,426 $3,562 1 $961 2 2 2029-2034
Site is located in Sawyer Creek reachshed and is most cost-effective step towards Sawyer Creek
TSS reduction target. Located on land owned by City. Evaluation for Fox Tail Lane site to also
include Oakwood & 20th Site to determine most cost-effective treatment system. Current
analysis shows Fox Tail Lane site alone is most cost-effective.
Sawyer Creek Oakwood & 20th / Fox Tail Lane
New Wet Ponds (SMPs 29A & 29B)15.7 56.1 4.4% 2.7% $1,465,000 $1,976,700 $145,950 $9,296 8 $2,602 10 2 2029-2034
Alternative to Fox Tail Lane. Accounts for combination of both Oakwood & 20th and Fox Tail Lane
new wet basins being implemented in series. Evaluation of Fox Tail Lane pond will consider both
Fox Tail Lane and Oakwood & 20th locations to determine optimum location and treatment
ability. Fox Tail Lane is preferred site and inclusion of Oakwood & 20th to provide treatment is
series is not as cost-effective.
Sawyer Creek Westhaven Golf Course West New
Wet Pond (SMP 35)15.3 91.1 4.3% 4.3% $86,000 $2,155,500 $96,584 $6,313 3 $1,060 3 Future Unknown
Lake
Winnebago
Hoffmaster - East & West New Wet
Ponds (SMPs 37 & 38)20.9 58.4 2.3% 1.1% $0 $7,418,600 $279,007 $13,350 13 $4,778 18 5 2044-2049
Site identified as part of Fernau Watershed SWMP and is a public-private partnership project that
would be located on private land. Project implementation would occur in conjunction with
expansion of private development. Schedule may change (occur sooner or later) dependent on
private aspect of project.
Lake Butte
des Morts
Lakeshore Park Wet Ponds Retrofit
(SMP 39)4.7 29.4 1.9% 2.1% $0 $429,900 $44,688 $9,508 9 $1,520 7 Future Unknown
Lake Butte
des Morts
Riverside - North New Wet Pond
(SMP 40)4.3 24.6 1.8% 1.8% $0 $597,900 $32,307 $7,513 6 $1,313 4 N/A N/A Site eliminated from consideration. Area is reserved for future cemetery use.
Table K-2
Comparison of Potential SMPs for Implementation Plan
Stormwater Management Plan Update
City of Oshkosh, WI
Annualized Cost per
Ton of TSS
Removed
Annualized Cost per
Pound of TP
Removed Priority Years
Estimated Land
Acquisition
Cost
Estimated
Construction
Cost
Total
Annualized
Cost
Implementation Planning NotesReachshed Project
TSS
Reduction
(tons/yr)
TP
Reduction
(lbs/yr)
TSS %
Reduction -
Reachshed
Basis
TP % Reduction
- Reachshed
Basis
SMP Comparison Table.xlsx 9/21/2022
$ Rank $ Rank
Table K-2
Comparison of Potential SMPs for Implementation Plan
Stormwater Management Plan Update
City of Oshkosh, WI
Annualized Cost per
Ton of TSS
Removed
Annualized Cost per
Pound of TP
Removed Priority Years
Estimated Land
Acquisition
Cost
Estimated
Construction
Cost
Total
Annualized
Cost
Implementation Planning NotesReachshed Project
TSS
Reduction
(tons/yr)
TP
Reduction
(lbs/yr)
TSS %
Reduction -
Reachshed
Basis
TP % Reduction
- Reachshed
Basis
Sawyer Creek Sawyer Creek - Abbey Ave New Wet
Pond (SMP 42)6.6 33.6 1.9% 1.6% $0 $1,503,400 $56,803 $8,607 7 $1,691 9
Sawyer Creek Sawyer Creek - Golden Ave New
Wet Pond (SMP 43)6.0 32.1 1.7% 1.5% $0 $589,300 $29,210 $4,868 2 $910 1
Lake
Winnebago
Fair Acres/Murdock - Enhanced
Settling Retrofit 3.1 26.4 0.3% 0.5% $0 $1,193,712 $80,712 $26,017 19 $3,061 13 N/A N/A
Site eliminated from consideration. Not feasible due to inadequate residence time for enhanced
settling.
Lake
Winnebago
Fernau Watershed - North Main
Enhanced Setting Retrofit 0.9 29.5 0.1% 0.6% $0 $1,284,920 $92,697 $107,967 23 $3,148 14 Future Unknown
Lake
Winnebago
Libbey-Nicolet - Enhanced Settling
Retrofit 10.4 105.9 1.2% 2.0% $0 $2,088,840 $144,246 $13,828 14 $1,362 5 Future Unknown
Sawyer Creek 9th & Washburn Enhanced Settling
Retrofit 2.2 60.1 0.6% 2.9% $0 $1,033,032 $86,168 $39,148 21 $1,434 6 4 2039-2044
Site is located in Sawyer Creek reachshed and represents a step towards advanced treatment
levels that would be needed to ultimately comply with high TP reductions required by TMDL.
Implementation schedule assumes additional WDNR guidance regarding this technology is
available and a preliminary evaluation of the technology has been completed to understand
costs and verify it is a cost-effective practice.
All Rain Gardens - Residential Land $0 $1,250 $40 $50,000 22 $6,004 19 Future Unknown
All Biofilters - Industrial Land $0 $20,800 $3,509 $25,000 18 $10,158 21 Future Unknown
All Biofilters - Institutional Land $0 $25,600 $3,962 $30,000 20 $8,356 20 Future Unknown
All Biofilters - Commercial Land $0 $25,600 $4,540 $19,000 16 $12,610 22 Future Unknown
Sawyer Creek Formalize & Integrate Leaf
Management Program 0 0.2 0.0% 0.1%Future Unknown
Implementation of leaf management program will be dependent on results on future study
(scheduled for 2027)
Fox River Formalize & Integrate Leaf
Management Program 0 0.1 0.0% 0.0%Future Unknown
Implementation of leaf management program will be dependent on results on future study
(scheduled for 2027)
All Research SMPs with O&M
Agreements Not Found 89 367.0 Varies Varies 1 2023 & Further Research scheduled to begin in 2023, schedule to obtain O&M agreements is uncertain.
All Research previously unidentified
Non-Regional SMPs 1 2024-2025 Research scheduled to being in 2024, schedule to obtain O&M agreements is uncertain.
Would depend on # implemented
Would depend on # implemented
Sites are in Sawyer Creek reachshed and are both cost-effective steps towards Sawyer Creek TSS
reduction target. Preliminary engineering to evaluate both Golden Ave and Abbey Ave Pond as
treatment areas overlap. Preferred site would be selected and then advanced for implementation.
Abbey Avenue site includes diversion sewer to maximize pollutant reductions. Added costs for
diversion sewer makes this site less cost effective. Evaluation to consider diversion sewer further.
Diversion sewer can potentially be implemented at a future date as part of road reconstruction to
lower cost of pavement replacement.
3 2034-2039
Reductions are unknown
Would depend on # implemented
Would depend on # implemented
SMP Comparison Table.xlsx 9/21/2022
Project Reachshed Type Years Item Description/Notes
Storm Water Utility Billing Database Updates All
Non-
Structural On-Going Continual updates to storm water utility billing database is made regularly as
development occurs and new aerial photographs are obtained.
Review flood control studies/projects for
opportunities to achieve pollution reduction as
a co-benefit
All Structural On-Going
Continue to review of flood studies/flood mitigation projects that are completed by
the City and where feasible incorporate pollution reduction measures.
Screen development sites for opportunities to
create a public-private partnership to enhance
pollutant reduction as part of development
All Structural
On-Going / As
projects occur
As developments (new or redevelopment) are first discussed with the City review to
determine if there is the possibility for a public-private partnership to maximize
benefits to the City. An example could be having a portion of the ROW treated by the
SMP included as part of the development.
Evaluate incorporation of SMPs into road
reconstruction projects All Structural
On-Going / As
projects occur
The City currently implements inlets with sumps as part of road reconstruction
projects. As part of the project planning and design review opportunities associated
with the road reconstruction to incorporate additional SMPs into the design to
maximize the pollution reduction achieved.
Implement non-regional SMPs associated with
other City projects All Structural
On-Going / As
projects occur
Implement non-regional SMP as part of various other City project such as parking lot
reconstruction, building reconstruction, etc. Meet City Municipal Code requirements
as a minimum level of pollution reduction and review the site to determine if
additional treatment can be feasible and cost-effective.
Research and verify existing O&M Agreements,
or obtain O&M Agreements for Additional
Existing Non-Regional SMPs (Sites
Constructed in Last 18 months)
All Non-
Structural 2023
Research sites where an O&M agreement could not be found further to identify if
one is in place. If not in place, work through Site Plan review process to obtain
agreement as part of final approval for the project. Priority is given to recent sites as
they were provided a Conditional Approval pending completion of an O&M
agreement.
Further consideration & study of Municipal
Code modifications to require increased
pollution reductions
All Non-
Structural 2023-2024
Conduct outreach with other City Departments (City Manager, Community
Development, Economic Development, etc) to consider benefits and drawbacks to
code modifications. Complete further study to understand impacts of code
modifications. Develop recommendations for implementation of code changes.
Potential implementation of Municipal Code
modifications All Non-
Structural 2024 Implement the Municipal Code modification recommended (if any) as part of the
study conducted in 2023-2024.
Research and verify existing O&M Agreements,
or obtain O&M Agreements, for Additional
Existing Non-Regional SMPs (Older Sites)
All Non-
Structural 2024-2025
Research sites that were constructed more than 18 months ago further and make
initial attempt to obtain O&M agreements. Develop protocol for further efforts to
obtain O&Ms if initial attempt is unsuccessful. Includes coordination with other City
Departments (Attorney, Community Development, Inspection Services) to work
towards obtaining agreements.
Research previously unidentified Non-
Regional SMPs All Non-
Structural 2024-2025
Research sites to collect SWMP and calculate pollution control. Research O&M
agreements and work towards obtaining O&M agreements as necessary in
conjunction with implementation plan items for O&M agreements.
Build WinSLAMM models for SWIP ponds (6
ponds - three currently assuming 80% TSS
control, three are not included due to lack of
data)
Sawyer Creek Non-
Structural 2026
The SWIP was constructed in two phases. The initial three ponds were built in
2004/2005 and the City does not have documentation of water quality
performance. These ponds are not included as SMPs in the current study. The
second phase included three ponds that were identified as achieving 80% TSS
reduction per WDNR Tech Std 1001.
Additional evaluation of leaf management
program All Non-
Structural 2027 Schedule anticipates additional guidance from WDNR and/or additional studies.
Also anticipate additional/updated tree size and leaf canopy coverage data.
Preliminary design study for feasibility of
enhanced settling All Non-
Structural 2028-2029
Schedule anticipates WDNR technical standard in place prior to start of study. Study
scheduled to allow for incorporation into 2030-2032 City SWMP update for
planning of future projects.
Citywide SWMP Update All
Non-
Structural
2030-2032
2040-2042
2050-2052
Regular updates at approximately 8-10 yr cycle. May adjust schedule or complete
pieces of study if changes, guidance, development, or other project related aspects
dictate. Study would include evaluation of new technology & potential alternative
compliance mechanisms such as pollutant trading. Update implementation plan.
Table K-3
Other Projects for Implementation Plan
Stormwater Management Plan Update
City of Oshkosh, WI
Oshkosh TMDL Implementation Plan Summary_v2.xlsx 8/10/2022
Table K-4
TMDL COMPLIANCE SUMMARY AND IMPLEMENTATION PLAN
Sawyer Creek (TMDL Reach 30)
Upper Fox & Wolf Rivers TMDL
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
No Controls Loads (per 2022 Citywide Stormwater Plan)354 2104
TMDL REDUCTION TARGETS 207 1801 58.4% 85.6%
With Controls Current Load Reductions (per 2022 Citywide Stormwater Plan)98 425 27.8% 20.2%
With Controls Remaining Loads (per 2022 Citywide Stormwater Plan)256 1679
Reduction Requirements Achieved?NO NO
Remaining gap (negative value) or Excess reduction (positive value)-108 -1376
BENCHMARK DESCRIPTION OF MEASURE IMPLEMENTATION DATE
IMPACTED
AREA (ac)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
1 Storm Water Utility Billing Database Updates On-Going Citywide 0 0 0.0% 0.0% 98 425 27.8% 20.2%
2 Review flood control studies/projects for opportunities to achieve pollution reduction as
a co-benefit On-Going Citywide 0 0 0.0% 0.0% 98 425 27.8% 20.2%
3 Screen development sites for opportunities to create a public-private partnership to
enhance pollutant reduction as part of development On-Going / As projects occur Citywide 0 0 0.0% 0.0% 98 425 27.8% 20.2%
4 Evaluate incorporation of SMPs into road reconstruction projects On-Going / As projects occur Citywide 0 0 0.0% 0.0%98 425 27.8% 20.2%
5 Implement non-regional SMPs associated with other City projects On-Going / As projects occur Citywide 0 0 0.0% 0.0%98 425 27.8% 20.2%
6 Research and verify existing O&M Agreements, or obtain O&M Agreements for Additional
Existing Non-Regional SMPs (14 sites)
2023 (recent sites)
2024 & Beyond (older sites)256 23 102 6.5% 4.8% 121 527 34.3% 25.0%
7 Further consideration & study of Municipal Code modifications to require increased
pollution reductions 2023-2024 Citywide 0 0 0.0% 0.0% 121 527 34.3% 25.0%
8 Potential implementation of Municipal Code modifications 2024 Citywide 0 0 0.0% 0.0% 121 527 34.3% 25.0%
9 Research previously unidentified Non-Regional SMPs (13 sites) 2024-2025 Unknown Unknown Unknown Unknown Unknown 121 527 34.3% 25.0%
10 Build WinSLAMM models for SWIP ponds (6 ponds - three currently assuming 80% TSS
control, three are not included due to lack of data)2026 Unknown Unknown Unknown Unknown Unknown 121 527 34.3% 25.0%
11 Additional evaluation of leaf management program 2027 Citywide 0 0 0.0% 0.0% 121 527 34.3% 25.0%
12 Preliminary design study for feasibility of enhanced settling 2028-2029 Citywide 0 0 0.0% 0.0% 121 527 34.3% 25.0%
13 Fox Tail Lane Wet Detention Basin (SMP 29B)2029-2034 162 15 56 4.2% 2.6% 136 583 38.5% 27.7%
14 Citywide SWMP Update 2030-2032 Citywide 0 0 0.0% 0.0% 136 583 38.5% 27.7%
15 Sawyer Creek - Abbey Ave (SMP 42) or Sawyer Creek - Golden Ave Wet Detention Basin
(SMP 43)2034-2039 81 7 34 1.9% 1.6% 143 616 40.4% 29.3%
16 9th & Washburn Enhanced Phosphorus Retrofit (Reg-10)2039-2044 366 2 60 0.6% 2.9% 145 676 41.0% 32.1%
17 Citywide SWMP Update 2040-2042 Citywide 0 0 0.0% 0.0% 145 676 41.0% 32.1%
18 Pheasant Creek Dry Basin Retrofit (SMP 7)2049-2054 87 3 18 0.9% 0.9% 148 694 41.9% 33.0%
19 Citywide SWMP Update 2050-2052 Citywide 0 0 0.0% 0.0% 148 694 41.9% 33.0%
20 Integrate Pollution Control Impacts from Redevelopment & Mixed Development (Assumes
Current Code Requirements)Annual (2022-2051) 132 11 33 3.0% 1.6% 159 727 44.9% 34.6%
BENCHMARK Consideration of New Development Impact IMPLEMENTATION DATE IMPACTED
AREA (ac)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
21 Integrate Pollution Control Impacts from New Development (Assumes Current Code
Requirements)Annual (2022-2051) 720 101 330 21.3% 12.4% 260 1057 54.7% 39.7%
121 561
Future Implementation Items
DESCRIPTION OF MEASURE IMPLEMENTATION DATE
IMPACTED
AREA (ac)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
Formalize & Integrate Leaf Management Program Unknown 17 0 2 0.0% 0.1%
Construct Miles Kimball Dry Basin Retrofit (SMP 16B)Unknown 15 2 6 0.6% 0.3%
Construct New Westhaven Golf Course West Wet Detention Basin (SMP 35) Unknown 235 15 91 4.3% 4.3%
Added Base Load from New Development
INCREMENTAL MEASURE TREATMENT
PERFORMANCE CUMULATIVE REACHSHED REDUCTION
Assessment Date: August, 2022
Oshkosh TMDL Implementation Plan Summary_v3.xlsx 9/21/2022
Table K-5
TMDL COMPLIANCE SUMMARY AND IMPLEMENTATION PLAN
Lake Butte Des Morts (TMDL Reach 73)
Upper Fox & Wolf Rivers TMDL
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
No Controls Loads (per 2022 Citywide Stormwater Plan)242 1392
TMDL REDUCTION TARGETS 48 1192 20.0% 85.6%
With Controls Current Load Reductions (per 2022 Citywide Stormwater Plan)56 255 23.2% 18.3%
With Controls Remaining Loads (per 2022 Citywide Stormwater Plan)186 1137
Reduction Requirements Achieved?YES NO
Remaining gap (negative value) or Excess reduction (positive value)8 -937
BENCHMARK DESCRIPTION OF MEASURE IMPLEMENTATION DATE
IMPACTED
AREA (ac)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
1 Storm Water Utility Billing Database Updates On-Going Citywide 0 0 0.0% 0.0% 56 255 23.2% 18.3%
2 Review flood control studies/projects for opportunities to achieve pollution reduction as
a co-benefit On-Going Citywide 0 0 0.0% 0.0% 56 255 23.2% 18.3%
3 Screen development sites for opportunities to create a public-private partnership to
enhance pollutant reduction as part of development On-Going / As projects occur Citywide 0 0 0.0% 0.0% 56 255 23.2% 18.3%
4 Evaluate incorporation of SMPs into road reconstruction projects On-Going / As projects occur Citywide 0 0 0.0% 0.0%56 255 23.2% 18.3%
5 Implement non-regional SMPs associated with other City projects On-Going / As projects occur Citywide 0 0 0.0% 0.0%56 255 23.2% 18.3%
6 Research and verify existing O&M Agreements, or obtain O&M Agreements for Additional
Existing Non-Regional SMPs (11 sites)
2023 (recent sites)
2024 & Beyond (older sites)334 16 58 6.6% 4.2% 72 313 29.8% 22.5%
7 Further consideration & study of Municipal Code modifications to require increased
pollution reductions 2023-2024 Citywide 0 0 0.0% 0.0% 72 313 29.8% 22.5%
8 Washburn St/Westowne Ave Wet Detention Basin Retrofit (SMP 6) 2024-2029 76.6 1.9 0.1 0.8% 0.0% 74 313 30.6% 22.5%
9 Potential implementation of Municipal Code modifications 2024 Citywide 0 0 0.0% 0.0% 74 313 30.6% 22.5%
10 Research previously unidentified Non-Regional SMPs (9 sites) 2024-2025 Unknown Unknown Unknown Unknown Unknown 74 313 30.6% 22.5%
11 Additional evaluation of leaf management program 2027 Citywide 0 0 0.0% 0.0% 74 313 30.6% 22.5%
12 Preliminary design study for feasibility of enhanced settling 2028-2029 Citywide 0 0 0.0% 0.0% 74 313 30.6% 22.5%
13 Citywide SWMP Update 2030-2032 Citywide 0 0 0.0% 0.0% 74 313 30.6% 22.5%
14 Citywide SWMP Update 2040-2042 Citywide 0 0 0.0% 0.0% 74 313 30.6% 22.5%
15 Citywide SWMP Update 2050-2052 Citywide 0 0 0.0% 0.0% 74 313 30.6% 22.5%
16 Integrate Pollution Control Impacts from Redevelopment & Mixed Development (Assumes
Current Code Requirements)Annual (2022-2051) 68 8 23 3.2% 1.7% 82 336 33.7% 24.2%
BENCHMARK Consideration of New Development Impact IMPLEMENTATION DATE IMPACTED
AREA (ac)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
17 Integrate Pollution Control Impacts from New Development (Assumes Current Code
Requirements)Annual (2022-2051) 900 83 380 24.4% 18.9% 165 716 48.4% 35.6%
98 620
Future Implementation Items
DESCRIPTION OF MEASURE IMPLEMENTATION DATE
IMPACTED
AREA (ac)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
Lakeshore Park Ponds Retrofit (SMP 39)Unknown 74 5 29 1.9% 2.1%
Added Base Load from New Development
Assessment Date: August, 2022
INCREMENTAL MEASURE TREATMENT
PERFORMANCE CUMULATIVE REACHSHED REDUCTION
Oshkosh TMDL Implementation Plan Summary_v2.xlsx 8/17/2022
Table K-6
TMDL COMPLIANCE SUMMARY AND IMPLEMENTATION PLAN
Fox River - Lake Butte Des Morts to Lake Winnebago (TMDL Reach 74)
Upper Fox & Wolf Rivers TMDL
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
No Controls Loads (per 2022 Citywide Stormwater Plan)557 3023
TMDL REDUCTION TARGETS 111 2588 20.0% 85.6%
With Controls Current Load Reductions (per 2022 Citywide Stormwater Plan)213 865 38.3% 28.6%
With Controls Remaining Loads (per 2022 Citywide Stormwater Plan)344 2158
Reduction Requirements Achieved?YES NO
Remaining gap (negative value) or Excess reduction (positive value)102 -1723
BENCHMARK DESCRIPTION OF MEASURE IMPLEMENTATION DATE
IMPACTED
AREA (ac)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
1 Storm Water Utility Billing Database Updates On-Going Citywide 0 0 0.0% 0.0% 213 865 38.3% 28.6%
2 Review flood control studies/projects for opportunities to achieve pollution reduction as
a co-benefit On-Going Citywide 0 0 0.0% 0.0% 213 865 38.3% 28.6%
3 Screen development sites for opportunities to create a public-private partnership to
enhance pollutant reduction as part of development On-Going / As projects occur Citywide 0 0 0.0% 0.0% 213 865 38.3% 28.6%
4 Evaluate incorporation of SMPs into road reconstruction projects On-Going / As projects occur Citywide 0 0 0.0% 0.0%213 865 38.3% 28.6%
5 Implement non-regional SMPs associated with other City projects On-Going / As projects occur Citywide 0 0 0.0% 0.0%213 865 38.3% 28.6%
6 Research and verify existing O&M Agreements, or obtain O&M Agreements for Additional
Existing Non-Regional SMPs (29 sites)
2023 (recent sites)
2024 & Beyond (older sites)208 3 9 0.5% 0.3% 216 874 38.8% 28.9%
7 Further consideration & study of Municipal Code modifications to require increased
pollution reductions 2023-2024 Citywide 0 0 0.0% 0.0% 216 874 38.8% 28.9%
8 Potential implementation of Municipal Code modifications 2024 Citywide 0 0 0.0% 0.0% 216 874 38.8% 28.9%
9 Research previously unidentified Non-Regional SMPs (2 sites) 2024-2025 Unknown Unknown Unknown Unknown Unknown 216 874 38.8% 28.9%
10 Additional evaluation of leaf management program 2027 Citywide 0 0 0.0% 0.0% 216 874 38.8% 28.9%
11 Preliminary design study for feasibility of enhanced settling 2028-2029 Citywide 0 0 0.0% 0.0% 216 874 38.8% 28.9%
12 Citywide SWMP Update 2030-2032 Citywide 0 0 0.0% 0.0% 216 874 38.8% 28.9%
13 Citywide SWMP Update 2040-2042 Citywide 0 0 0.0% 0.0% 216 874 38.8% 28.9%
14 Citywide SWMP Update 2050-2052 Citywide 0 0 0.0% 0.0% 216 874 38.8% 28.9%
15 Integrate Pollution Control Impacts from Redevelopment & Mixed Development (Assumes
Current Code Requirements)Annual (2022-2051) 255 16 52 2.9% 1.7% 232 926 41.7% 30.6%
BENCHMARK Consideration of New Development Impact IMPLEMENTATION DATE IMPACTED
AREA (ac)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
16 Integrate Pollution Control Impacts from New Development (Assumes Current Code
Requirements)Annual (2022-2051) 60 6 25 1.1% 0.8% 238 951 42.2% 31.1%
7 38
Future Implementation Items
DESCRIPTION OF MEASURE IMPLEMENTATION DATE
IMPACTED
AREA (ac)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
Formalize & Integrate Leaf Management Program Unknown 1 0 0 0.0% 0.0%
Added Base Load from New Development
Assessment Date: August, 2022
INCREMENTAL MEASURE TREATMENT
PERFORMANCE CUMULATIVE REACHSHED REDUCTION
Oshkosh TMDL Implementation Plan Summary_v2.xlsx 8/17/2022
Table K-7
TMDL COMPLIANCE SUMMARY AND IMPLEMENTATION PLAN
Lake Winnebago (TMDL Reach 75)
Upper Fox & Wolf Rivers TMDL
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
No Controls Loads (per 2022 Citywide Stormwater Plan)893 5167
TMDL REDUCTION TARGETS 179 4423 20.0% 85.6%
With Controls Current Load Reductions (per 2022 Citywide Stormwater Plan)275 1282 30.8% 24.8%
With Controls Remaining Loads (per 2022 Citywide Stormwater Plan)618 3885
Reduction Requirements Achieved?YES NO
Remaining gap (negative value) or Excess reduction (positive value)96 -3141
BENCHMARK DESCRIPTION OF MEASURE IMPLEMENTATION DATE
IMPACTED
AREA (ac)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
1 Storm Water Utility Billing Database Updates On-Going Citywide 0 0 0.0% 0.0% 275 1282 30.8% 24.8%
2 Review flood control studies/projects for opportunities to achieve pollution reduction as
a co-benefit On-Going Citywide 0 0 0.0% 0.0% 275 1282 30.8% 24.8%
3 Screen development sites for opportunities to create a public-private partnership to
enhance pollutant reduction as part of development On-Going / As projects occur Citywide 0 0 0.0% 0.0% 275 1282 30.8% 24.8%
4 Evaluate incorporation of SMPs into road reconstruction projects On-Going / As projects occur Citywide 0 0 0.0% 0.0%275 1282 30.8% 24.8%
5 Implement non-regional SMPs associated with other City projects On-Going / As projects occur Citywide 0 0 0.0% 0.0%275 1282 30.8% 24.8%
6 Research and verify existing O&M Agreements, or obtain O&M Agreements for Additional
Existing Non-Regional SMPs (33 sites)
2023 (recent sites)
2024 & Beyond (older sites)730 48 199 5.3% 3.9% 323 1481 36.1% 28.7%
7 Further consideration & study of Municipal Code modifications to require increased
pollution reductions 2023-2024 Citywide 0 0 0.0% 0.0% 323 1481 36.1% 28.7%
8 Potential implementation of Municipal Code modifications 2024 Citywide 0 0 0.0% 0.0% 323 1481 36.1% 28.7%
9 Research previously unidentified Non-Regional SMPs (15 sites) 2024-2025 Unknown Unknown Unknown Unknown Unknown 323 1481 36.1% 28.7%
10 Additional evaluation of leaf management program 2027 Citywide 0 0 0.0% 0.0% 323 1481 36.1% 28.7%
11 Preliminary design study for feasibility of enhanced settling 2028-2029 Citywide 0 0 0.0% 0.0% 323 1481 36.1% 28.7%
12 Citywide SWMP Update 2030-2032 Citywide 0 0 0.0% 0.0% 323 1481 36.1% 28.7%
13 Citywide SWMP Update 2040-2042 Citywide 0 0 0.0% 0.0% 323 1481 36.1% 28.7%
14 Construct Hoffmaster East and West Wet Detention Basin (SMPs 37 & 38) 2044-2049 153 21 58 2.3% 1.1% 343 1539 38.5% 29.8%
15 Citywide SWMP Update 2050-2052 Citywide 0 0 0.0% 0.0% 343 1539 38.5% 29.8%
16 Integrate Pollution Control Impacts from Redevelopment & Mixed Development (Assumes
Current Code Requirements)Annual (2022-2051) 396 45 132 5.1% 2.6% 389 1672 43.6% 32.4%
BENCHMARK Consideration of New Development Impact IMPLEMENTATION DATE IMPACTED
AREA (ac)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
17 Integrate Pollution Control Impacts from New Development (Assumes Current Code
Requirements)Annual (2022-2051) 690 85 311 8.6% 5.5% 474 1983 47.8% 35.1%
99 487
Future Implementation Items
DESCRIPTION OF MEASURE IMPLEMENTATION DATE
IMPACTED
AREA (ac)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
Construct Island View Estates Dry Basin Retrofit (SMP 15)Unknown 43 2 13 0.2% 0.3%
Construct Bowen Street Wet Detention Basin (SMP 26)Unknown 229 13 53 1.4% 1.0%
Construct Libbey-Nicolet Enhanced Phosphorus Retrofit (Reg-9) Unknown 419 10 106 1.2% 2.0%
Added Base Load from New Development
Assessment Date: August, 2022
INCREMENTAL MEASURE TREATMENT
PERFORMANCE CUMULATIVE REACHSHED REDUCTION
Oshkosh TMDL Implementation Plan Summary_v2.xlsx 8/17/2022
Table K-8
TMDL COMPLIANCE SUMMARY AND IMPLEMENTATION PLAN
Neenah Slough (TMDL Reach LF06)
Upper Fox & Wolf Rivers TMDL
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
No Controls Loads (per 2022 Citywide Stormwater Plan)2 20
TMDL REDUCTION TARGETS 1 8 52.0% 40.5%
With Controls Current Load Reductions (per 2022 Citywide Stormwater Plan)0 0 0.0% 0.0%
With Controls Remaining Loads (per 2022 Citywide Stormwater Plan)2 20
Reduction Requirements Achieved?NO NO
Remaining gap (negative value) or Excess reduction (positive value)-1 -8
BENCHMARK DESCRIPTION OF MEASURE IMPLEMENTATION DATE
IMPACTED
AREA (ac)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
1 Storm Water Utility Billing Database Updates On-Going Citywide 0 0 0.0% 0.0% 0 0 0.0% 0.0%
2 Review flood control studies/projects for opportunities to achieve pollution reduction as
a co-benefit On-Going Citywide 0 0 0.0% 0.0% 0 0 0.0% 0.0%
3 Screen development sites for opportunities to create a public-private partnership to
enhance pollutant reduction as part of development On-Going / As projects occur Citywide 0 0 0.0% 0.0% 0 0 0.0% 0.0%
4 Evaluate incorporation of SMPs into road reconstruction projects On-Going / As projects occur Citywide 0 0 0.0% 0.0%0 0 0.0% 0.0%
5 Implement non-regional SMPs associated with other City projects On-Going / As projects occur Citywide 0 0 0.0% 0.0%0 0 0.0% 0.0%
6 Further consideration & study of Municipal Code modifications to require increased
pollution reductions 2023-2024 Citywide 0 0 0.0% 0.0% 0 0 0.0% 0.0%
7 Potential implementation of Municipal Code modifications 2024 Citywide 0 0 0.0% 0.0% 0 0 0.0% 0.0%
8 Additional evaluation of leaf management program 2027 Citywide 0 0 0.0% 0.0% 0 0 0.0% 0.0%
9 Preliminary design study for feasibility of enhanced settling 2028-2029 Citywide 0 0 0.0% 0.0% 0 0 0.0% 0.0%
10 Citywide SWMP Update 2030-2032 Citywide 0 0 0.0% 0.0% 0 0 0.0% 0.0%
11 Citywide SWMP Update 2040-2042 Citywide 0 0 0.0% 0.0% 0 0 0.0% 0.0%
12 Citywide SWMP Update 2050-2052 Citywide 0 0 0.0% 0.0% 0 0 0.0% 0.0%
BENCHMARK Consideration of New Development Impact IMPLEMENTATION DATE IMPACTED
AREA (ac)
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
TSS
(tons/yr)
TP
(lbs/yr)
TSS
%
TP
%
13 Integrate Pollution Control Impacts from New Development (Assumes Current Code
Requirements)Annual (2022-2051) 60 6 26 65.2% 38.2% 6 26 65.2% 38.2%
7 48Added Base Load from New Development
Assessment Date: August, 2022
INCREMENTAL MEASURE TREATMENT
PERFORMANCE CUMULATIVE REACHSHED REDUCTION
Oshkosh TMDL Implementation Plan Summary_v2.xlsx 8/17/2022