Yes, at low levels. 2 PFAS were detected, all below EPA's 2024 limits.
Also detected, no federal limit: PFBA, PFHxA.
East Bay MUD is a public water system drawing on surface water, based in Oakland, California, serving about 1.4 million people, including Alameda, Danville, Alamo, Pleasant Hill, Crockett, Diablo. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 21 times across 6 sampling points between Apr 2023 and Dec 2025.
| PFAS | Detected | Highest | Worst point avg | EPA limit |
|---|---|---|---|---|
| PFBA Perfluorobutanoic acid |
2 of 21 | 5.2 ppt | 1.3 ppt | none |
| PFHxA Perfluorohexanoic acid |
2 of 21 | 3.5 ppt | 1.7 ppt | none |
Not detected: ADONA, PFDA, 9Cl-PF3ONS, 11Cl-PF3OUdS, PFUnA, PFDoA, PFOA, PFOS, PFNA, PFHxS, PFHpA, PFBS, 6:2 FTS, NMeFOSAA, NEtFOSAA, PFPeS, HFPO-DA, PFHpS, NFDHA, PFEESA, PFMBA, PFPeA, PFMPA, 8:2 FTS, 4:2 FTS, PFTrDA, PFTA.
Lithium, tested in the same program: not detected.
In April 2024 EPA set enforceable limits of 4 ppt for PFOA and PFOS, 10 ppt each for PFHxS, PFNA and GenX, and a hazard index of 1 for mixtures. Utilities were given until 2029 to comply. In May 2026 EPA proposed keeping only the PFOA and PFOS limits and moving that deadline to 2031. Until that proposal is final, the 2024 limits stand.
Compliance is judged on a running annual average at each entry point, so we show the average at this system's worst sampling point next to its single highest result. UCMR 5 results do not by themselves put a utility in or out of compliance.
Levels here are under EPA's limits, so no treatment is required. If you want them lower anyway, a certified reverse osmosis system under the sink handles drinking water, and a whole-house carbon filter also takes out the chlorine or chloramine your utility adds.
All 707 tested systems in California
94501 94502 94506 94507 94523 94525 94526 94528 94530 94541 94542 94544 94545 94546 94547 94549 94552 94553 94556 94563 94564 94568 94569 94572 94577 94578 94579 94580 94582 94583 94595 94596 94597 94598 94601 94602 94603 94605 94606 94607 94608 94609 94610 94611 94612 94613 94618 94619 94621 94702 94703 94704 94705 94706 94707 94708 94709 94710 94720 94801 94803 94804 94805 94806
As reported by the utility to EPA. Neighbouring ZIPs are often split between systems; your water bill names yours.
Well & Tap. "PFAS in East Bay MUD water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID CA0110005. https://wellandtap.com/pfas/california/east-bay-mud/
Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID CA0110005). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.
