Ensuring a proposed SFPUC water recapture facility
in the Sunol Valley maintains stream flow benefits and fish passage for
The SFPUC is proposing a project to recapture stream flows that will be released from Calaveras Reservoir and bypassed around the Alameda Creek Diversion Dam as part of steelhead trout restoration and mitigations for the Calaveras Dam project. The recapture project has changed from a proposed rubber dam in the Sunol Valley to proposed construction of an infiltration gallery under Alameda Creek, to the current project: passive water recapture through a quarry pit in the Sunol Valley. The SFPUC intends to recapture an annual average of 9800 acre-feet of water that percolates into the Sunol Groundwater Basin, by pumping it out of quarry Pit-F2 into San Antonio Reservoir or the Sunol Water Treatment Plant, essentially mining the groundwater. The SFPUC proposes construction from 2017-2018.
While the project represents an improvement over previous project designs and avoids construction impacts to Alameda Creek, there are some concerns about potential project impacts on surface flows in Alameda Creek, and on fish passage and aquatic habitat in the Sunol Valley and Niles Canyon. The SFPUC proposes to operate the quarry pond as a reservoir, but the connection between groundwater in the Sunol Basin with surface flow in Alameda Creek is unclear. The SFPUC issued a Notice of Preparation of an Environmental Impact Report in June 2015. The Alameda Creek Alliance, Alameda County Water District and Save The Frogs submitted extensive scoping comments regarding these concerns.