California utilities 1,501 to 1,600.
Each serves 185 to 215 people, as it reports to EPA. Your ZIP code finds yours faster.
1,501 to 1,600 of 2,762, by people served
Every utility EPA sampled for PFAS under UCMR 5, any other community system serving 3,300 people or more, and any smaller one with results from 2020 on, from the state. Other systems appear in ZIP code results. People served is what each utility reports to EPA. Data: EPA SDWIS 2026 Q3, UCMR 5 and EPA’s 2012 to 2019 compliance results, and California State Water Resources Control Board, Division of Drinking Water.
Where to go next
- Read your utility’s own reportIt covers contaminants these pages don’t show, and its own latest results.How to read it
- Every contaminantLegal limits, health goals and what handles each one.All contaminants
- Filters, checkedEvery filter TapBuff has checked against a certifier’s listing, with five-year costs.Compare filters