HomeMy WebLinkAboutOshkosh_Raw Water Diversion Vault Modification_Approval 2023
August 9, 2023
DIANE BARTLETT CLERK Acknowledgement of Receipt
CITY OF OSHKOSH
215 CHURCH AVE
PO BOX 1130
OSHKOSH WI 54903-1130
Project Number:
PWSID#:
DNR Region:
County:
W-2023-0774
47104574
NER
WINNEBAGO
SUBJECT: WATER SYSTEM FACILITIES PLAN AND SPECIFICATION APPROVAL
Dear Ms. Bartlett:
The Wisconsin Department of Natural Resources, Division of Environmental Management, Bureau of Drinking
Water and Groundwater, is conditionally approving plans and specifications for the following project. An
engineering report or information of sufficient detail to meet the requirements of s. NR 811.09(3), Wis. Adm.
Code, was submitted along with the plans and specifications.
Water system name: Oshkosh Waterworks
Date received: 8/2/2023
Engineering firm: Jacobs Engineering Group, Inc.
Professional Engineer: Linda Mohr
Regional DNR Contact: Jamie Douglas, 2984 Shawano Ave, Green Bay, WI 54313, (920) 362-6629,
jamie.douglas@wisconsin.gov
DNR Plan Reviewer: Bradley Siefker, 101 South Webster Street, Madison, WI 53703, (608) 419-7636,
bradley.siefker@wisconsin.gov
Project description: On behalf of the City of Oshkosh (City), Jacobs Engineering Group, Inc. submitted plans
and specifications for the modification of the raw water diversion vault to allow for intake and raw water
transmission main cleaning. The plans and specifications are hereby approved by the department subject to the
conditions below.
Background: The City’s water supply system presently includes a surface water treatment plant drawing raw
water from Lake Winnebago, three finished water clearwells, four elevated storage tanks, and the distribution
system composed of two pressure zones. The water treatment plant includes two treatment trains that each
include rapid mix, flocculation, sedimentation, dual media gravity filtration, ozone contactors, and granular
activated carbon contactors. Chemical addition consists of gas chlorine and ammonia to form chloramines for
disinfection purposes, fluorosilicic acid for community dental health purposes, blended phosphate for distribution
system corrosion control purposes, and sodium hydroxide for pH adjustment and distribution system corrosion
control purposes.
The City utilizes a primary 60-inch diameter intake with a backup 36-inch diameter intake to supply water the to
the treatment plant. The 36-inch diameter intake discharges into a pre-treatment basin before a 30-inch diameter
State of Wisconsin
DEPARTMENT OF NATURAL RESOURCES
101 S. Webster Street
Box 7921
Madison WI 53707-7921
Tony Evers, Governor
Adam N. Payne, Secretary
Telephone 608-267-7556
Toll Free 1-888-936-7463
TTY Access via relay - 711
dnr.wi.gov
wisconsin.gov
Project Number: W-2023-0774 Page 2 of 3
raw water transmission main discharges to the treatment plant. Due to potential water quality issues associated
with the pre-treatment basin, the City has reportedly not used this intake, the pre-treatment basin, or the
transmission main since 2005. The primary 60-inch diameter intake discharges to a diversion vault which allows
water to either discharge to the pre-treatment basin or be directed toward the treatment plant through a 60-inch
diameter raw water transmission main. Normal operation for the City bypasses the pre-treatment basin and water
discharges from the vault directly to the treatment plant.
The City completed a condition assessment of the intakes in May of 2023 and discovered the 60-inch diameter
intake pipes and transmission mains to be between 50 and 75% full of sediment. It is assumed similar sediment
deposition may be occurring in the 36-inch diameter intake and 30-inch diameter raw water transmission main.
Due to the reduced capacity of the 60-inch diameter pipes the City has proposed to flush water through the intakes
and transmission mains from the shore into the lake. The City has proposed to modify the diversion vault top slab
to provide access and accommodate the temporary fittings for connection of raw water pumps to flush the 60-inch
diameter intakes and transmission mains. The department is not approving the intake cleaning or any
modifications to allow for additional connections of the 36-inch diameter intake or 30-inch diameter
transmission to the diversion vault at this time.
Diversion vault modifications: Two L-shaped slabs of existing pre-cast concrete planks from the existing
diversion vault roof slab will be removed. The slabs removed will be approximately 5.5-foot square openings with
an additional approximately 3-foot by 3.5-foot extension. The extensions of the L-shaped openings will be
covered with gasketed plate bolted to the concrete roof. A new 5-foot square gasketed aluminum access hatch and
support frame will be installed over the 5.5-foot square openings. The access hatches will be supplied by Nystrom
and include a will be double door access hatch with a locking cover. The frame of the hatches will be provided
with a channel drain to divert water from the hatch interior. The channel drain will discharge to the side of the
vault top slab through 1.5-inch-thick stainless steel drain piping with a rodent screen will be sealed to the concrete
roof slab to prevent infiltration between the pipe and concrete. Any voids between the concrete roof and the
access hatches will be sealed with non-shrink grout.
Approval conditions related to Chapters NR 810 and NR 811, Wis. Adm. Code:
1. A resident project representative shall be designated by the water supply owner or by the agent retained
by the owner. The resident project representative shall be knowledgeable regarding the proposed
construction and be able to ensure the improvements are being constructed in accordance with the
department approved plans, specifications, and conditions of the approval. The project representative
shall be present on the work site as needed to assure proper construction and installation of the
improvements. (s. NR 811.11, Wis. Adm. Code)
2. Plans and specifications shall be submitted to the department for review and the subsequent written
approval prior to any additional modifications or additional connections to the diversion vault (s. NR
811.08 (1), Wis. Adm. Code)
3. The owner or owner’s agent shall provide notification to Jamie Douglas from the department’s Green Bay
office upon completion of the improvements so that she can inspect the completed improvements and
issue written authorization prior to placing the improvements in service, if she deems necessary. (s. NR
810.26 (1), Wis. Adm. Code)
Approval constraints: The project was reviewed in accordance with ss. 281.34 and 281.41, Wis. Stats. for
compliance with Chapters NR 108, NR 810, NR 811 and NR 820, Wis. Adm. Code and is hereby approved in
accordance with ss. 281.34 and 281.41, Wis. Stats. subject to the conditions listed above. This approval is valid
for two years from the date of approval. If construction or installation of the improvements has not commenced
within two years the approval shall become void and a new application must be made and approval obtained prior
to commencing construction or installation.
Project Number: W-2023-0774 Page 3 of 3
This approval is based on the applicant’s representation that the plans and specifications submitted to the
department are complete and accurately represent the project being approved. Discovery that the applicant failed
to submit complete and accurate plans and specifications may void this approval.
Be advised that this project may require permits or approvals from other federal, state or local authorities. For
example, a certificate of authority from the Public Service Commission of Wisconsin may be required per s.
196.49, Wis. Stats. and ch. PSC 184, Wis. Adm. Code.
Appeal rights: If you believe that you have a right to challenge this decision, you should know that the
Wisconsin Statutes and administrative rules establish time periods within which requests to review Department
decisions must be filed. To request a contested case hearing pursuant to s. 227.42, Wis. Stats., you have 30 days
after the decision is mailed, or otherwise served by the Department, to serve a petition for hearing on the
Secretary of the Department of Natural Resources. Requests for contested case hearings must be made in
accordance with ch. NR 2, Wis. Adm. Code. Filing a request for a contested case hearing does not extend the 30
day period for filing a petition for judicial review. For judicial review of a decision pursuant to ss. 227.52 and
227.53, Wis. Stats., you must file your petition with the appropriate circuit court and serve the petition on the
Department within 30 days after the decision is mailed. A petition for judicial review must name the Department
of Natural Resources as the respondent.
STATE OF WISCONSIN
DEPARTMENT OF NATURAL RESOURCES
For the Secretary
Bradley D. Siefker, P.E.
Public Water Engineering Section
Bureau of Drinking Water and Groundwater
cc: James Rabe – City of Oshkosh (by email)
Linda Mohr – Jacobs Engineering Group Inc., Milwaukee (by email)
Jamie Douglas – DNR, Green Bay (by email)
JaNelle Merry – DNR, Green Bay (by email)
PSC – Madison (by email)