PFAS · New Hampshire
PFAS in New Hampshire drinking water: EPA’s final survey results
EPA’s national PFAS survey (UCMR 5) tested 49 of the community water systems that serve homes in New Hampshire. 18 found at least one of 29 PFAS above the laboratory reporting level, and 10 had a PFOA or PFOS sampling-location yearly average at or above EPA’s 4.0 ppt limit. Samples were collected from January 2023 to December 2025.
Data as of EPA UCMR 5 final release, August 2026 (file dated Aug 28, 2026) · EPA SDWIS 2026Q2 (file dated Jul 9, 2026). How we build these pages
PFOA was the compound New Hampshire community systems found most often: 15 of 49 tested systems measured it above the reporting level. Across the country, 35% of surveyed community systems found at least one PFAS; in New Hampshire the share is 37%. The largest New Hampshire system with a detection, Manchester Water Works, serves 123,500 people and found 1 of the 29 compounds.
Which PFAS were found most often in New Hampshire
Each row counts the New Hampshire community water systems where that compound was measured above the reporting level at least once. A detection is a measurement, not a violation: most of these compounds have no federal limit.
| Compound | Systems where found | Systems tested | Share |
|---|---|---|---|
| PFOA | 15 | 49 | 31% |
| PFHxA | 10 | 49 | 20% |
| PFOS | 8 | 49 | 16% |
| PFPeA | 8 | 49 | 16% |
| PFBA | 5 | 49 | 10% |
| PFBS | 4 | 49 | 8% |
| PFHpA | 3 | 49 | 6% |
| PFHxS | 2 | 49 | 4% |
New Hampshire systems with the most PFAS found
The 10 surveyed community water systems that found the most different PFAS, with PFOA and PFOS compared to EPA’s 4.0 ppt limits on the yearly average at the highest sampling location. Larger systems come first when counts tie.
| Water system | People served | PFAS found (of 29) | PFOA | PFOS |
|---|---|---|---|---|
| Portsmouth Water Works NH1951010 | 33,000 | 8 | 6.0 ppt at or above the MCL | 4.5 ppt at or above the MCL |
| Exeter Water Dept NH0801010 | 12,236 | 7 | 2.8 ppt below the MCL | 2.0 ppt below the MCL |
| Aquarion Water/Nh NH1051010 | 34,000 | 5 | 2.4 ppt below the MCL | 2.3 ppt below the MCL |
| Hampstead Area Water NH1031010 | 7,153 | 5 | 6.3 ppt at or above the MCL | 3.8 ppt below the MCL |
| Litchfield NH1371010 | 6,920 | 4 | 7.5 ppt at or above the MCL | — not detected above the reporting level |
| Rye Water Dist NH2041010 | 4,300 | 4 | 6.9 ppt at or above the MCL | 6.9 ppt at or above the MCL |
| Salem Water Dept NH2051010 | 21,000 | 3 | 7.5 ppt at or above the MCL | — not detected above the reporting level |
| Hudson Water Dept NH1201010 | 16,700 | 3 | 8.0 ppt at or above the MCL | — not detected above the reporting level |
| Seabrook Water Dept NH2111010 | 14,000 | 3 | 4.0 ppt at or above the MCL | 2.7 ppt below the MCL |
| Jaffrey Water Works NH1221010 | 3,800 | 3 | 6.0 ppt at or above the MCL | 2.8 ppt below the MCL |
Counties with the most systems that found PFAS
- Rockingham County 11 of 12 surveyed systems
- Hillsborough County 4 of 9 surveyed systems
- Merrimack County 2 of 6 surveyed systems
- Cheshire County 1 of 2 surveyed systems