Is San Diego Tap Water Safe? What San Diego, City of’s EPA Records Show
San Diego, City of, which serves about 1,385,379 people in California, reported no PFAS above reporting limits in the EPA’s UCMR5 monitoring (2023-2025). Non-detect means not found above the EPA’s reporting floor in that round — not that the water was never tested again. Its most recent EPA-record lead 90th-percentile was non-detect (below the reporting limit) — under the current 15 ppb action level. The system has 2 health-based violations on its federal SDWA record.
See the full interactive report for this system — every PFAS analyte, lead and copper rounds, violations, and the filter that handles what was found: open the San Diego report → Or check YOUR exact ZIP: check your water by ZIP →
Beyond PFAS: state-record results over an EPA limit
- tthm: 87 ug/L (highest sample 2025-05-13)
- uranium: 66 pCi/L (highest sample 2025-08-26)
- gross alpha: 73.3 pCi/L (highest sample 2025-08-26)
These are the highest samples in the state/EPA record for this system — a snapshot, not a current reading; the utility’s Consumer Confidence Report is the official current record.
Common questions about San Diego water
Is San Diego's tap water safe to drink?
The records show tthm, uranium, gross alpha above a current EPA limit or action level — the details, with dates, are in the sections above. That is a system-level occurrence record, not a verdict on any individual tap. These are system-level records for public water systems, not a reading of any individual home’s tap, and they do not cover private wells. Confirm your own utility’s current Consumer Confidence Report, and test your tap if you’re unsure.
Does San Diego have PFAS in its drinking water?
San Diego, City of reported no PFAS above reporting limits in UCMR5 monitoring.
Who supplies San Diego's drinking water?
San Diego, City of (PWSID CA3710020) serves about 1,385,379 people, per EPA SDWIS records. A metro area is usually served by more than one water system — this page covers the area’s largest. Suburbs and neighboring towns often have their own systems with their own results; check your exact ZIP for yours.
How do I check my exact address?
Water systems report by system, not by address. Enter your ZIP on the water checker to see the system(s) serving it and what each reported.
Statewide, 18.7% of California’s UCMR5-tested systems reported PFOA or PFOS over the EPA limit — see the California water page.
Other large systems in California
Los Angeles Oakland San Jose San Francisco western Riverside County (Moreno Valley, Hemet, Perris), California
See the 100 largest US water systems, water quality by state, and the national PFAS data study.
Sources: EPA UCMR5 occurrence data, Feb 2026 release (~95% complete; final reporting 2026) (2026-06); lead/copper + violations: EPA SDWIS via ECHO; population served: EPA SDWIS via ECHO (system-reported population served). PWSID CA3710020. Public-domain federal/state records; assembly by WaterByTheBook. Built 2026-07-25. Plain-markdown mirror: https://waterbythebook.com/md/san-diego.md