CheckPFAS

City overview · San Joaquin County

PFAS in Stockton, CA

High Risk

EPA UCMR 5 tested 2 public water systems serving the Stockton area across 12 ZIP codes. At least one utility serving Stockton has PFAS above the EPA's enforceable limit.

Water systems tested
2
Systems above EPA limits
2
ZIP codes covered
12
County
San Joaquin County, California

Plain English

01What this means for Stockton

Across the 2 public water systems tested in the Stockton area under EPA UCMR 5, one or more measured a PFAS compound above the federal Maximum Contaminant Level. Contamination varies by utility and neighborhood — find your exact ZIP code below to see the system that serves you. If you're in an affected area, an NSF/ANSI 53 or 58 certified filter (carbon block or reverse osmosis) is the most reliable way to reduce PFAS at the tap.

By utility

02Water systems serving Stockton

  1. CALIFORNIA WATER SERVICE - STOCKTON

    1 detected · 1 above limit · PWSID CA3910001

    High Risk
  2. CITY OF STOCKTON

    1 detected · 1 above limit · PWSID CA3910012

    High Risk

By ZIP code

03Find your exact result

Contamination can differ block to block. Select your ZIP code for the precise reading at the utility that serves your address.

Source & Methodology

About this data

Source
EPA UCMR 5
Sampling period
January 2023 – December 2025
Aggregation
2 utilities across 12 ZIP codes
Detection threshold (MRL)
~1.5–2 ppt

City-level figures aggregate the individual public water systems tested under EPA UCMR 5 whose service area falls within the Stockton area. Values reflect water quality at the treatment plant; your home's plumbing can affect what reaches your tap. Select your ZIP above for the utility-specific reading.