Water Quality in San Francisco, CA
Detailed water quality data for San Francisco, California including contaminant levels, EPA comparisons, AquaScore™ grading, and treatment recommendations.
Water utility: San Francisco Public Utilities Commission.
Water source: Hetch Hetchy Reservoir (Yosemite), local groundwater.
Key Contaminants Found
- Chromium (hexavalent)
- Total trihalomethanes (TTHMs)
- Haloacetic acids (HAA5)
- Lead
- Chloroform
San Francisco gets pristine snowmelt from Hetch Hetchy Reservoir in Yosemite — so pure it's one of only a few US cities exempt from filtration requirements. Lead from old building plumbing is the primary concern at the tap.