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City of Gilroy tap water

Above a federal PFAS limit

At least one sampling point at City of Gilroy averaged above the 4 ppt federal limit: PFOA up to 5.8 ppt.

PFAS test results

Highest average at any one sampling point, from EPA's UCMR 5 testing (2024–2025), against the levels EPA set in 2024. ND = not detected above EPA's reporting level. EPA's comparison rounds like this: an average of 4.05 ppt or more counts as above the 4 ppt PFOA/PFOS limit, and 15 ppt or more counts as above the 10 ppt level for PFHxS, PFNA and GenX.

PFOAlevel 4 ppt
5.8 ppt
PFOSlevel 4 ppt
2.9 ppt
PFHxSlevel 10 ppt (proposed to rescind)
1.8 ppt
PFNAlevel 10 ppt (proposed to rescind)
ND
HFPO-DA (GenX)level 10 ppt (proposed to rescind)
ND

Hazard index (PFHxS, PFNA, GenX, PFBS mix): 0.18 (limit 1, EPA comparison threshold 1.5).

All 8 detected compounds at this system (single highest result)
CompoundHighest resultResults above reporting level
lithium11 µg/L4 of 14
PFBS9.4 ppt5 of 14
PFOA8 ppt6 of 14
PFPeA7.8 ppt5 of 14
PFHxA7 ppt6 of 14
PFOS5.8 ppt1 of 14
PFHpA3.6 ppt1 of 14
PFHxS3.5 ppt1 of 14

Read this as a screening result, not a compliance finding. UCMR 5 samples are occurrence data. Legal compliance is judged on a running annual average from the utility's own monitoring, reported to the state. PFOA and PFOS at 4 ppt are in force; EPA has proposed to rescind the PFHxS, PFNA, GenX and hazard-index levels.

Violations and lead

1 health-based violation began since 2021-10-26 (1 limit exceedance, 0 treatment-technique; 0 still open). Most recent began 2022-06-01.

Contaminant groupViolations
Nitrate1

Health-based means a limit exceedance or a missed treatment requirement. Many violations are fixed within weeks; a count says nothing about severity. Missed-sample (monitoring) violations are not counted.

Lead 90th percentile: 2.0 ppb for the period ending 2024-12-31 (action level 15 ppb). This is a system-wide statistic, not your home's tap; lead usually comes from household plumbing and service lines.

Lithium: highest result 11 µg/L. EPA's non-regulatory reference concentration is 10 µg/L (results above 15 are counted as above it). Lithium has no federal drinking-water limit.

What helps, and what does not

For PFAS, a point-of-use reverse-osmosis unit or a carbon filter certified to NSF/ANSI 53 or 58 for PFAS reduction is the realistic home step, with a lab test first. Be aware that today's certified claim is reduction to under 20 ppt combined PFAS, above the 4 ppt federal limit, so certification does not prove a filter reaches the federal level. Water softeners and iron filters do not remove PFAS. Read the whole-house PFAS answer.

Common questions

Is the tap water in City of Gilroy safe to drink?

At least one sampling point at City of Gilroy averaged above the 4 ppt federal limit: PFOA up to 5.8 ppt. 1 health-based violation recorded since 2021-10-26 (0 not yet closed). Lead 90th percentile 2.0 ppb in the sampling period ending 2024-12-31 (action level 15 ppb). This is a summary of public EPA data, not a guarantee about the water at your tap.

Does City of Gilroy have PFAS in its water?

Yes. EPA's 2023–2025 testing detected 7 of 29 PFAS compounds at City of Gilroy.

Not medical or legal advice. Results describe the utility's system, not your tap. Compare with your utility's annual Consumer Confidence Report.

Sources and freshness

Public-water-system facts, violations and lead/copper results: EPA ECHO SDWA download (SDWIS snapshot 2026-10-13). PFAS and lithium results: EPA UCMR 5 final data (sampling 2023–2025). Both are U.S. government works, downloaded 2026-10-26. Numbers are computed by the published method; the same fields are in the open data files.