County · California
San Francisco County, California: drinking water records
This overview covers 28 ZIP codes and 6 community water systems in San Francisco County. It also stands in for 0 ZIP codes whose utility has too little EPA data for a page of its own.
System population figures are summed from EPA registry records and can overlap where wholesalers and retail systems serve the same people. They are not a Census county-population estimate.
Water systems with the most complete records
| Water system | People served | PFAS survey results | PFAS found | Health-based violations | Lead, 9 in 10 homes at or below |
|---|---|---|---|---|---|
| Sfpuc City Distribution Division CA3810011 | 848,019 | 720 | 0 | 0 | 0 ppb |
| Presidio of San Francisco CA3810700 | 3,500 | 120 | 7 | 0 | 0 ppb |
| Arbor Village MI0040223 | 670 | 0 | 0 | 3 | 1 ppb |
| San Francisco Regional Water System CA3810001 | 600 | 310 | 0 | 0 | 0 ppb |
| Treasure Island CA3810702 | 3,864 | 0 | 0 | 0 | 100 ppb |
| Hhw&p Moccasin Compound-Sfpuc CA3810003 | 410 | 0 | 0 | 0 | 0 ppb |
ZIP reports in San Francisco County
No ZIP report in this county is published yet.
Sources and scope
EPA UCMR 5 occurrence data, samples collected 2023-01-03 – 2026-06-17, final release, August 2026 (file dated Aug 28, 2026); EPA SDWIS via ECHO, 2026Q2 extract (file dated Jul 9, 2026); EPA service-area boundaries v3.0; Census 2020 ZCTAs. Page generated 2026-09-03.
Counts cover the systems that report this county to EPA. A water system may cross county lines. "Found" means at least one result at or above the laboratory reporting level; it is not a compliance finding.