HomeMy WebLinkAbout22. 22-110MARCH 8, 2022 22-110 RESOLUTION
(CARRIED___7-0_____LOST________LAID OVER________WITHDRAWN________)
PURPOSE: DIRECT STAFF TO ENTER INTO CONTRACT AMENDMENT
WITH JACOBS ENGINEERING GROUP, INC. TO EXPLORE
POSSIBILITY OF EXTENDING EXISTING UNDERGROUND
CLEARWELLS’ SERVICE LIFE ($140,000.00)
INITIATED BY: DEPARTMENT OF PUBLIC WORKS
WHEREAS, the City and Jacobs Engineering Group, Inc., previously entered into
a contract in which Jacobs would provide the City with services related to the study and
design of replacement clearwell structures for the temporary storage of treated drinking
water; and
WHEREAS, additional services added to the contract would explore the
possibility of extending the existing underground clearwells’ service life.
NOW, THEREFORE, BE IT RESOLVED by the Common Council of the City of
Oshkosh that the proper City officials are authorized and directed pursuant to Section
12-16 of the Municipal Code to enter into an amended contract with Jacobs Engineering
Group, Inc. for the purpose of conducting a physical inspection of the existing clearwells
and groundwater sampling and providing an analysis and recommendation in relation
to the potential for extending the service life of the existing underground clearwell
structures.
BE IT FURTHER RESOLVED that an amendment to the contract with Jacobs
Engineering Group, Inc. is approved and said City officials are authorized and directed
to take those steps necessary to implement the terms and conditions of the final contract.
BE IT FURTHER RESOLVED that should it be more efficient and/or cost effective
for sampling, testing or other services to be contracted directly by the City in coordination
with the work required by Jacobs that the proper City staff are authorized and directed
to work with Jacobs Engineering Group, Inc. to identify those services that may be
necessary and directly contract with those providers as may be necessary to support this
project.
BE IT FURTHER RESOLVED that money for this purpose is hereby appropriated
from:
Acct. No. 03221810-7206-64110 Water Capital Fund/Capital Construction-WFP
Infrastrc Imprvmt
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TO: Honorable Mayor and Members of the Common Council
FROM: Steven M. Gohde, Assistant Director of Public Works /
Utilities General Manager
DATE: March 3, 2022
RE: Direct Staff to Enter into Contract Amendment with Jacobs Engineering
Group, Inc. (Jacobs) to Explore Possibility of Extending Existing
Underground Clearwells’ Service Life ($140,000)
BACKGROUND
The Water Filtration Plant stores treated drinking water in structures called clearwells,
prior to pumping it into the water distribution system. These clearwells are buried, cast-
in-place concrete structures that range in age from approximately 60 to over 100 years
old. The Wisconsin Department of Natural Resources (WDNR) Sanitary Surveys of the
City’s water system identified deficiencies with these structures and directed the City to
replace the clearwells. The 2014 inspection of the clearwells indicated they were in fair
condition.
The City hired Jacobs, formerly CH2MHill, in 2012 to study the replacement of the
clearwells and has entered into preliminary and final design contracts since then. To
date, the City has entered into contracts totaling approximately $1,445,000 for study and
design of the replacement of the clearwells and directly-related work.
The State of Wisconsin Administrative Code prohibits storing drinking water below
groundwater to prevent potential contamination of the drinking water should the tank
leak. Public Informational Meetings (PIM) were held in 2017 and in 2021 to present the
concept of aboveground storage tanks to replace existing underground tanks. Following
the 2021 PIM, several residents expressed concern about the appearance of the
aboveground tanks, including the visual impact of having the large structures along the
shoreline of Lake Winnebago. City Staff and Jacobs have collected and responded to
questions related to the replacement of the tanks and placed these on the City’s website.
During this time, Jacobs was keeping the two (2) regulatory agencies, WDNR and the
Public Service Commission of Wisconsin, updated on the status of the design.
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On February 4th, the City and Jacobs met virtually with WDNR to discuss the clearwells
replacement. During the meeting, the WDNR indicated they would be willing to
entertain an option which would allow the existing underground (below groundwater)
clearwells to remain in service. While this meeting was not the place to discuss technical
options, the WDNR staff made it clear they would expect a physical inspection of the
existing clearwells to be completed and that “additional mitigation efforts are necessary
to ensure adequate treatment if the integrity of the tanks would become compromised
and was undetected between inspections”. Additional groundwater sampling and
testing would need to be performed to determine what, if any, contaminants are present
in the groundwater. The inspection and sampling is anticipated to take six to eight (6 –
8) months to complete and would cost approximately $140,000. Until this work is
complete, we will not know the viability or estimated cost of pursuing this option.
We currently estimate that the best extension of life the clearwells could achieve is 20 –
40 years. At such time, it is anticipated the reconstruction of the clearwells would be
required. WDNR staff have made it very clear that, at such time as the clearwells are
reconstructed, the requirements of the State of Wisconsin Administrative Code must be
complied with. This means that eventually, the City will have to construct aboveground
structures to maintain the storage above groundwater.
ANALYSIS
Based on the information currently available, the City has two (2) options to move
forward with at this time. The first is to proceed with the investigation to determine if
the existing underground clearwells can be rehabilitated to add an estimated 20 – 40 years
of service life. The second option is to build new aboveground storage tanks, with an
expected service life of 60 – 80 years. The shape and architectural finishes of the tanks
will then need to be determined.
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The first option will require the existing center underground clearwell be abandoned and
a new pump station built aboveground within the existing center clearwell footprint.
The new pump station will house any additional mitigation barrier needed to meet the
WDNR requirement for additional mitigation efforts. At this time, UV disinfection is
assumed to be needed. Proceeding with this direction will result in the splitting of the
current proposed project into two (2) separate projects. The ozone system replacement,
emergency generator replacement, and auxiliary improvements would move forward as
a separate project, while the investigation into the condition of the existing clearwells
proceeds. The estimated cost of the investigation is $140,000. Upon completion of the
investigation, assuming no issues are found to eliminate this option, a reasonable cost
estimate will be developed. Based on the extensive experience of the Jacobs engineering
team, they have provided potential costs in the table below. This option will require the
City to physically inspect the tanks more often, perhaps annually, and the City will incur
additional operating costs for the mitigation barrier. The pump station built with this
option will need to be expanded when the aboveground tanks are constructed.
The second option, to build aboveground storage tanks with a pump station, has been
studied in depth. Aboveground tanks meet the Wisconsin Administrative Code and will
provide the highest level of protection to the stored drinking water. If Council wishes to
proceed with this option, the contract amendment is not needed and the ozone system
replacement, emergency generator, auxiliary work, and the new tanks will be bid as one
(1) project. Staff will then bring a resolution to Council to determine the shape and
general location of the aboveground tanks and to establish an ad hoc committee to
address the aesthetics of the tanks, site, and adjacent area.
The table on the next page provides a cost comparison of the two (2) aboveground tanks’
options and extending the life of the existing clearwells. The extending the life of the
existing clearwells option is based on Jacobs engineering team’s extensive experience and
is subject to change, pending the outcome of the inspection and groundwater sampling
and analysis.
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Project Component
At-Grade
Circular
At-Grade
Square and
Rectangular
Extend Existing
Clearwells’ Service Life
Proposed tank size
(gallons)
Two 84’
diameter tanks
with 28’ wall
height and 34’
to top of domed
roof (1,000,000
gal. each).
South, 92’
square. North,
84’ x 130’
rectangle. Both
tanks have 17’
wall height and
are 18’ to top of
sloped roof
(850,000 and
1,150,000 gal.,
respectively).
Existing North and South
Clearwells would be
maintained. The center
clearwell would be
demolished and the new
pump station and treatment
would be installed. Resulting
capacity total is 1,900,000 gal.
Inspection and
groundwater sampling
and analysis $140,000
Mitigation proposal to
WDNR and design $190,000
Storage tanks cost $5,398,600 $9,548,300
Clearwells repairs $2,600,000 - $3,800,000
Pump station’s cost $7,301,700 $7,301,700 $4,746,100
New mitigation barrier
and pump station
redesign, assumed UV
disinfection $4,155,000
Subtotal $12,700,300 $16,850,000 $11,831,100 – $13,031,100
Expected life 60 – 100 years 60 – 100 years 20 – 40 years
Ozone system $7,804,800 $7,804,800 $7,804,800
Emergency generators $4,707,900 $4,707,900 $4,707,900
Demolition/site work $3,357,000 $3,357,000 $3,357,000
Auxiliary
improvements $1,210,600 $1,210,600 $1,210,600
TOTAL COST $29,780,600 $33,930,300 $28,911,400 – $30,111,400
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FISCAL IMPACT
The estimated cost of the physical inspection of the existing clearwells and groundwater
sampling and analysis is $140,000. Funding for this is available in the 2021 Capital
Improvements Program (Account No. 03221810-7206-64110/Water Capital Fund/Capital
Construction-WFP Infrastrc Imprvmt).
RECOMMENDATIONS
Approval of this resolution will allow staff to negotiate and approve an agreement with
Jacobs to inspect the existing clearwells, sample and analyze the groundwater, and
determine if moving forward to develop a mitigation proposal for the WDNR to maintain
the existing tanks is feasible and allow for development of a more accurate estimate of
probable costs.
Failure of the resolution will result in staff placing a resolution on the next meeting to
provide direction on the shape of the aboveground storage tanks and to establish an ad
hoc committee for the aesthetics of the tanks, site, and adjacent area.
Approved,
John Fitzpatrick
Assistant City Manager
SMG/tlt