DATE: May 3, 2016
TO: Mayor and City Council
FROM: Director of Utilities & Environmental Services
SUBJECT
Title
Water Pollution Control Facility (WPCF) Headworks Rehabilitation Project: Approval of Plans and Specifications, and Call for Bids
End
RECOMMENDATION
Recommendation
That Council adopts the attached resolution (Attachment I) approving the plans and specifications for the WPCF Headworks Rehabilitation Project and calling for bids to be received on June 7, 2016.
Body
BACKGROUND
The City's WPCF provides treatment for wastewater collected from the City's residential and business communities. The facility treats an annual average flow of eleven million gallons per day (MGD) and meets current requirements to discharge treated effluent to the deep waters of the San Francisco Bay. All of the flow coming to the WPCF passes through the headworks and is conveyed through influent channels with grinders designed to break down large debris prior to pumping to downstream treatment processes. The Headworks Building was originally constructed in 1996 and is an essential facility at the WPCF. Given the location and the function of the headworks, the facility is expected to require major maintenance and overhaul more frequently than other facilities. Funding is approved in FY 2016 and FY 2017 Capital Improvement Program for Headworks Rehabilitation.
A recent structural inspection revealed substantial deterioration of the concrete on the interior deck of the influent channels located in the lower level of the Headworks Building caused by exposure to hydrogen sulfide, a corrosive gas and a common byproduct of sewer collection and conveyance. The protective coatings originally installed in the headworks had deteriorated over the years and in some areas had completely failed leading to substantial corrosion including loss of the cement covering the reinforcing steel in some areas. The Headworks Reha...
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