The Hetch Hetchy watershed, an area located in Yosemite National Park, provides approximately 85% of San Francisco's total water needs. Spring snowmelt runs down the Tuolumne River and fills Hetch Hetchy, the largest reservoir in the SFPUC system. This surface water in the Hetch Hetchy Reservoir is treated, but not filtered because it is of such high quality.
The Alameda and Peninsula Sources
Together the Alameda and Peninsula watersheds produce about 15% of the total water supply. The Alameda watershed, located in Alameda and Santa Clara Counties, contributes surface water supplies captured and stored in two reservoirs: Calaveras and San Antonio. The Sunol Filter Galleries located near the Town of Sunol, are a groundwater source supplying less than one percent of San Francisco's water. The Peninsula watershed in San Mateo County contributes surface water supplies captured and stored in lower and upper Crystal Springs and San Andreas Reservoirs and in two smaller reservoirs, Pilarcitos and Stone Dam. The 6 reservoirs in the Alameda and Peninsula watersheds capture rain and local runoff. Some also store Hetch Hetchy water for use by San Francisco. These local water sources and groundwater from the Sunol filter galleries are treated and filtered before delivery.
"Water for Our Future," a full-color brochure summarizing the SFPUC's water supply diversification projects, is now available.
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The San Francisco Public Utilities Commission has developed a Recycled Water Master Plan to provide guidance for implementing recycled water projects in San Francisco. Recycled water will help the City better meet its long-term water demands in a more reliable and sustainable manner.
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The SFPUC Wholesale Customer Demand Projections Technical Report is now available. This report was prepared for the San Francisco Public Utilities Commission by URS consultants. Read more
