PFAS in Washington Drinking Water — 29 ZIPs Tested

PFAS Contamination in Washington

ZipCheckup analyzed drinking water data across 726 ZIP codes in Washington for pfas contamination. 29 ZIP codes have reported pfas detections, and 14 have EPA violations on record.

The violation rate for pfas in Washington is 1.9% of all ZIP codes — roughly in line with the national average.

EPA Standard for PFAS

The EPA maximum contaminant level (MCL) for pfas is 4 ppt (PFOA/PFOS), governed by the PFAS NPDWR (2024). Water systems that exceed this limit must take corrective action and notify consumers.

Worst ZIP Codes for PFAS in Washington

These ZIP codes reported the highest pfas levels in Washington based on CCR reports and EPA data:

Lowest PFAS Levels in Washington

These ZIP codes had the lowest reported pfas detections in Washington:

Health Effects of PFAS

PFAS (per- and polyfluoroalkyl substances) are linked to cancer (kidney, testicular), thyroid disease, immune system suppression, reproductive problems, and elevated cholesterol. These "forever chemicals" persist in the body for years.

How to Remove PFAS From Drinking Water

The most effective treatment for pfas removal is Reverse Osmosis or Granular Activated Carbon. Look for filters certified under NSF 53 / NSF 58 standards.

Check Your ZIP Code

Use the ZipCheckup water quality search to see pfas data for your specific water system in Washington.