Water quality by county
in New Hampshire
EPA sampled public water systems across New Hampshire for PFAS under its UCMR 5 programme. Of the 10 counties, 4 have a reading above a federal limit and 0 have not been sampled at all — which is not a clean result, only an absence of one. Each county below shows what was found, at what concentration, and at which utility.
| county | Population | Worst result | Compound |
|---|---|---|---|
| Hillsborough County | 430,462 | 2.3× | PFOA · 9 ng/L |
| Rockingham County | 322,433 | 2.1× | PFOA · 8.5 ng/L |
| Cheshire County | 78,078 | 1.6× | PFOA · 6.6 ng/L |
| Merrimack County | 157,869 | 1.6× | PFOS · 6.5 ng/L |
| Belknap County | 65,257 | under the limit | — |
| Carroll County | 52,580 | under the limit | — |
| Coos County | 31,094 | under the limit | — |
| Grafton County | 93,045 | under the limit | — |
| Strafford County | 134,202 | under the limit | — |
| Sullivan County | 44,012 | under the limit | — |