No PFAS were detected in any of the 16 samples EPA's program collected.
City of San Diego is a public water system drawing on surface water, based in San Diego, California, serving about 1.4 million people, including Bonita, Chula Vista, Imperial Beach, La Mesa, Lemon Grove, National City. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 16 times across 4 sampling points between Jan 2023 and Dec 2023.
None of the 29 PFAS were found at or above EPA's minimum reporting levels (2 to 20 ppt depending on the compound).
Not detected: PFUnA, PFHxA, PFDoA, PFDA, PFOA, PFOS, PFHxS, NMeFOSAA, NEtFOSAA, 11Cl-PF3OUdS, PFPeA, PFTrDA, PFBS, PFMPA, PFHpS, PFPeS, NFDHA, PFEESA, 8:2 FTS, PFHpA, 9Cl-PF3ONS, PFTA, 4:2 FTS, 6:2 FTS, PFBA, HFPO-DA, ADONA, PFMBA, PFNA.
Lithium, tested in the same program: highest 65 ppb, detected in 15 of 16 samples. EPA's health-based screening level is 10 ppb.
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.
No PFAS action is needed on these results. If your water tastes or smells of chlorine, a whole-house city water filter is the usual fix.
All 707 tested systems in California
91902 91910 91911 91913 91915 91932 91941 91942 91945 91950 91977 92008 92014 92019 92020 92021 92025 92027 92037 92040 92064 92065 92067 92071 92075 92093 92101 92102 92103 92104 92105 92106 92107 92108 92109 92110 92111 92113 92114 92115 92116 92117 92119 92120 92121 92122 92123 92124 92126 92127 92128 92129 92130 92131 92134 92136 92139 92140 92145 92154 92161 92173 92182
As reported by the utility to EPA. Neighbouring ZIPs are often split between systems; your water bill names yours.
Well & Tap. "PFAS in City of San Diego water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID CA3710020. https://wellandtap.com/pfas/california/city-of-san-diego/
Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID CA3710020). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.
