PFAS in California Drinking Water — 21 ZIPs Tested
EPA data analysis for pfas in California drinking water systems
PFAS Contamination in California
ZipCheckup analyzed drinking water data across 2,630 ZIP codes in California for pfas contamination. 21 ZIP codes have reported pfas detections, and 1 have EPA violations on record.
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 California
These ZIP codes reported the highest pfas levels in California based on CCR reports and EPA data:
Lowest PFAS Levels in California
These ZIP codes had the lowest reported pfas detections in California:
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 California.
Worst ZIP Codes for PFAS in California
Ranked by highest pfas detection level.
| Rank | ZIP Code | City | Level Detected | EPA Limit | Status |
|---|---|---|---|---|---|
| 1 | 90630 | Cypress | 9.9 ppt | 3 ppt | Exceeds |
| 2 | 90680 | Stanton | 9.9 ppt | 3 ppt | Exceeds |
| 3 | 90721 | Los Alamitos | 9.9 ppt | 3 ppt | Exceeds |
| 4 | 92840 | Garden Grove | 9.9 ppt | 3 ppt | Exceeds |
| 5 | 92841 | Garden Grove | 9.9 ppt | 3 ppt | Exceeds |
| 6 | 92842 | Garden Grove | 9.9 ppt | 3 ppt | Exceeds |
| 7 | 92843 | Garden Grove | 9.9 ppt | 3 ppt | Exceeds |
| 8 | 92844 | Garden Grove | 9.9 ppt | 3 ppt | Exceeds |
| 9 | 92845 | Garden Grove | 9.9 ppt | 3 ppt | Exceeds |
| 10 | 92846 | Garden Grove | 9.9 ppt | 3 ppt | Exceeds |
| 11 | 95721 | Echo Lake | 4 ppt | 4 ppt | Within Limit |
| 12 | 95735 | Twin Bridges | 4 ppt | 4 ppt | Within Limit |
| 13 | 96150 | South Lake Tahoe | 4 ppt | 4 ppt | Within Limit |
| 14 | 96151 | South Lake Tahoe | 4 ppt | 4 ppt | Within Limit |
| 15 | 96152 | South Lake Tahoe | 4 ppt | 4 ppt | Within Limit |
| 16 | 96154 | South Lake Tahoe | 4 ppt | 4 ppt | Within Limit |
| 17 | 96155 | South Lake Tahoe | 4 ppt | 4 ppt | Within Limit |
| 18 | 96156 | South Lake Tahoe | 4 ppt | 4 ppt | Within Limit |
| 19 | 96157 | South Lake Tahoe | 4 ppt | 4 ppt | Within Limit |
| 20 | 96158 | South Lake Tahoe | 4 ppt | 4 ppt | Within Limit |
Lowest PFAS Levels in California
| ZIP Code | City | Level Detected |
|---|---|---|
| 96158 | South Lake Tahoe | 4 ppt |
| 96157 | South Lake Tahoe | 4 ppt |
| 96156 | South Lake Tahoe | 4 ppt |
| 96155 | South Lake Tahoe | 4 ppt |
| 96154 | South Lake Tahoe | 4 ppt |
| 96152 | South Lake Tahoe | 4 ppt |
| 96151 | South Lake Tahoe | 4 ppt |
| 96150 | South Lake Tahoe | 4 ppt |
| 95735 | Twin Bridges | 4 ppt |
| 95721 | Echo Lake | 4 ppt |
Cities with PFAS Data in California
294 cities in California have pfas testing data available.
+ 274 more cities