SCH Number 2020070367

Project Info

Title

Moccasin Creek Hatchery Permanent Recirculation Project

Description

The San Francisco Public Utility Commission (SFPUC), a department of the City and County of San Francisco, operates the Hetch Hetchy Water and Power System, which provides water to the California Department of Fish and Wildlife’s (CDFW’s) Moccasin Creek Fish Hatchery (Hatchery) from Moccasin Reservoir. In 2016, an emergency recirculation system was constructed by CDFW at the Hatchery (funded by SFPUC), which allowed the Hatchery to continue operating with a smaller fish inventory and with only 3 cubic feet per second (cfs) of inflow from Moccasin Reservoir. This emergency recirculation system successfully operated during SFPUC’s January 3, 2017 to March 4, 2017 shutdown, which temporarily eliminated water deliveries through the Mountain Tunnel to accommodate necessary inspections and maintenance. As a result of inspections and work performed during the 2017 Shutdown, SFPUC determined it would require multiple 60- to 100-day shutdowns over a 6-year period to complete the rehabilitation of Mountain Tunnel. Adding on to what was constructed in 2016, CDFW will be constructing a reuse system (Permanent Recirculation System) at the Hatchery using funding provided by SFPUC. The Permanent Recirculation System will accommodate water supply interruptions for periods of 60 to 100 days. The Permanent Recirculation System generally consists of installation of: 1) permanent power with backup generator and transfer switch; 2) a new sump for existing pumps; 3) drum filtration; 4) a safe platform access for existing aeration towers; and 5) a fish exclusion screen at the existing settling pond.

2 documents in project