PFAS above EPA’s limits in New Hampshire.
The short answer
9 utilities serving 222,708 people, as they report it, had a location averaging above a limit, most often PFOA (9) and PFOS (2). The largest is Manchester Water Works, whose highest PFOA average was 4.5 ppt, 1.1 times the limit. The furthest above is Hudson Water Dept, at twice the PFOA limit.
These are EPA’s survey results, not violations: the limits take effect April 26, 2029, and compliance will rest on each utility’s own monitoring. EPA has proposed changes to the rule; as of Oct. 13, 2026, none is final.
Utilities above a limit
Largest first. Each one’s highest location average is for the limit it is furthest above, with the single highest sample of the same PFAS; its report has every result.
| Utility | Based in | Serves | Above | Highest location average | Highest single sample |
|---|---|---|---|---|---|
| Manchester Water Works | Manchester | 123,500 | PFOA | PFOA 4.5 ppt1.1 times the limit | 5.0 ppt |
| Portsmouth Water Works | Portsmouth | 33,000 | PFOA, PFOS | PFOA 6.0 ppt1.5 times the limit | 7.0 ppt |
| Salem Water Dept | Salem | 21,080 | PFOA | PFOA 7.5 ppt1.9 times the limit | 8.5 ppt |
| Hudson Water Dept | Hudson | 16,700 | PFOA | PFOA 8.0 ppttwice the limit | 9.0 ppt |
| Hampstead Area Water | Hampstead | 7,153 | PFOA | PFOA 6.3 ppt1.6 times the limit | 7.2 ppt |
| Litchfield | Litchfield | 6,920 | PFOA | PFOA 7.5 ppt1.9 times the limit | 8.1 ppt |
| Londonderry | Londonderry | 6,255 | PFOA | PFOA 4.2 ppt1.05 times the limit | 6.4 ppt |
| Rye Water Dist | Rye | 4,300 | PFOA, PFOS | PFOA 7.0 ppt1.7 times the limit | 8.3 ppt |
| Jaffrey Water Works | Jaffrey | 3,800 | PFOA | PFOA 6.0 ppt1.5 times the limit | 6.6 ppt |
7 more utilities in New Hampshire had a single sample above a limit but no location average above, so they are not listed; each report shows the sample.
Results: EPA UCMR 5 occurrence data, file of Oct. 15, 2026, samples from Jan. 3, 2023 to June 17, 2026, averaged by sampling location as EPA’s final UCMR 5 data summary does. Every state, and the full data as a CSV; how this list is made. People served is what each utility reports.
Where to go next
- Manchester Water Works’s reportEvery PFAS result with its dates, and the certification claim that handles each.Open the report
- Every stateThe national list, the largest utilities above a limit, and the data to download.PFAS above EPA’s limits
- Filters certified for PFASRanked by certification and what they cost over five years.Best water filters for PFAS