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Utility Capital Projects
Department Project Title Project Number
Public Works Big Fossil Interceptor Rehabilitation Project UT2206
Project Description
Rehabilitate the 24 inch wastewater interceptor line from 3621 Holland St to 6029 Riviera Dr. The total distance of the interceptor
rehabilitated would be 7,250 linear feet. The intent is to utilize a trenchless construction method to the greatest extent possible to
rehabilitate this line, such as cured-in-place pipe (CIPP). The project includes three logical sections that could be completed as three
distinct phases. The sections are: 3621 Holland St to 3817 Diamond Loch W, 3817 Diamond Loch W to 6200 Glenview Dr, and
6200 Glenview Dr to 6029 Riviera Dr.

Project Justification
This section of reinforced concrete pipeline was constructed in the early 1970's. A series of collapses in recent years led staff to
inspect sections of this pipeline. Inspection revealed that the pipeline has significant deterioration due to hydrogen sulfide gas
(H2S). H2S gas eats away at the portion of pipe that does not carry the wastewater flow (roughly 50% of the pipe, the top portion of
the pipe). With the gases attacking the top portion of pipe, it can buckle under the weight of the ground above it, resulting in a pipe
collapse, and causing a sanitary sewer overflow. The typical thickness of reinforced concrete pipe is between 2 and 3 inches. Staff
was able to locate areas in the pipeline that had a thickness as low as a quarter of an inch. This is not just at isolated areas, this
corrosion is throughout the pipeline. With the installation of the CIPP, the H2S gases will not corrode the new pipeline and therefore
creating a pipeline that should have a life expectancy of more than 50 years.

Funding Source: Certificates of Obligation.

Project Schedule Beginning Date Ending Date History Fiscal Year Amount
Professional Services Proposed 2021-22 $2,510,000
Engineering/Design 10/2021 09/2022 Total $2,510,000
Land/ROW Acquisition
Construction 10/2022 09/2023
Other
Total Schedule 10/2021 09/2023
Sources of Funds Appr. To Date 2021‐22 Budget 2022‐23 Estimate 2023‐Completion Total Funding
General Obligation Bonds
Certificates of Obligation 0 2,510,000 0 0 $2,510,000
Federal/State Grants
Reserves
Sales Tax
Other
Total Funding $0 $2,510,000 $0 $0 $2,510,000

Project Costs To Date 2021‐22 Budget 2022‐23 Estimate 2023‐Completion Total Cost
Professional Services
Engineering/Design 0 310,000 0 0 $310,000
Land/ROW Acquisition
Construction 0 2,200,000 0 0 $2,200,000
Other
Total Costs $0 $2,510,000 $0 $0 $2,510,000
Operating Impact
No operating impact is anticipated.

Fiscal Year 2020‐21 2021‐22 2022‐23 2023‐24 2024‐25 Total Impact
Amount $0 $0 $0 $0 $0 $0

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