CheckPFAS

City overview · Santa Clara County

PFAS in San Jose, CA

High Risk

EPA UCMR 5 tested 5 public water systems serving the San Jose area across 28 ZIP codes. At least one utility serving San Jose has PFAS above the EPA's enforceable limit.

Water systems tested
5
Systems above EPA limits
2
ZIP codes covered
28
County
Santa Clara County, California

Plain English

01What this means for San Jose

Across the 5 public water systems tested in the San Jose 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 San Jose

  1. GREAT OAKS WC INC

    5 detected · 1 above limit · PWSID CA4310022

    High Risk
  2. SAN JOSE WATER

    3 detected · 1 above limit · PWSID CA4310011

    High Risk
  3. HGST INC

    1 detected · 0 above limit · PWSID CA4300791

    Low Level
  4. CITY OF SAN JOSE - EVG/EDV/COY

    1 detected · 0 above limit · PWSID CA4310020

    Low Level
  5. CITY OF SAN JOSE - NSJ/ALVISO

    1 detected · 0 above limit · PWSID CA4310019

    Low Level

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
5 utilities across 28 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 San Jose 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.