Thanks to the visionary engineers of the 20th century and the ongoing management of the San Francisco Public Utilities Commission, many Bay Area residents are blessed with some of the best drinking water in the nation. From the 2008 report on water quality:
The sources of drinking water (both tap water and bottled water) include rivers, lakes, streams, ponds, reservoirs, springs, and wells. For the SFPUC systems, the major water source originates from spring snowmelt flowing down the Tuolumne River to the Hetch Hetchy Reservoir, where it is stored. This pristine water source is located in the well-protected Sierra region and meets all federal and state criteria for watershed protection. Based on the SFPUC’s disinfection treatment practice, extensive bacteriological-quality monitoring, and high operational standards, the State has granted the Hetch Hetchy water source a filtration exemption. In other words, the source is so clean and protected that the SFPUC is not required to filter water from the Hetch Hetchy Reservoir.84% of the tap water for our town of Foster City comes from the Hetch Hetchy. Clean running water adds immeasurably to the quality of our lives, yet it's easy to take for granted. Here’s one taxpayer who doesn’t. Salud!