PFAS · Massachusetts
PFAS in Massachusetts drinking water: EPA’s final survey results
EPA’s national PFAS survey (UCMR 5) tested 261 of the community water systems that serve homes in Massachusetts. 144 found at least one of 29 PFAS above the laboratory reporting level, and 76 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 May 2026.
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
PFPeA was the compound Massachusetts community systems found most often: 110 of 261 tested systems measured it above the reporting level. Across the country, 35% of surveyed community systems found at least one PFAS; in Massachusetts the share is 55%. The largest Massachusetts system with a detection, Worcester Dpwp, Water Supply Division, serves 206,518 people and found 1 of the 29 compounds.
Which PFAS were found most often in Massachusetts
Each row counts the Massachusetts 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 |
|---|---|---|---|
| PFPeA | 110 | 261 | 42% |
| PFHxA | 102 | 261 | 39% |
| PFOA | 102 | 261 | 39% |
| PFBS | 71 | 261 | 27% |
| PFOS | 67 | 261 | 26% |
| PFBA | 48 | 261 | 18% |
| PFHpA | 25 | 261 | 10% |
| PFHxS | 24 | 261 | 9% |
| 6:2 FTS | 3 | 261 | 1% |
| 4:2 FTS | 1 | 261 | 0% |
| PFHpS | 1 | 261 | 0% |
| PFNA | 1 | 261 | 0% |
Massachusetts 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 |
|---|---|---|---|---|
| Duxbury Water Department MA4082000 | 16,387 | 10 | 6.3 ppt at or above the MCL | 34.7 ppt at or above the MCL |
| Abington/Rockland Joint Wtr. Works MA4001000 | 33,387 | 8 | 11.5 ppt at or above the MCL | 7.0 ppt at or above the MCL |
| North Attleboro Water Dept MA4211000 | 31,410 | 8 | 8.5 ppt at or above the MCL | 6.5 ppt at or above the MCL |
| Acton Water Supply District MA2002000 | 21,285 | 8 | 11.5 ppt at or above the MCL | 4.6 ppt at or above the MCL |
| Middleborough Water Supply MA4182000 | 15,350 | 8 | 9.5 ppt at or above the MCL | 4.5 ppt at or above the MCL |
| Marshfield Water Department MA4171000 | 34,000 | 7 | 6.9 ppt at or above the MCL | 2.3 ppt below the MCL |
| Bridgewater Water Department MA4042000 | 28,633 | 7 | 9.0 ppt at or above the MCL | 7.0 ppt at or above the MCL |
| Dartmouth Water Division MA4072000 | 24,696 | 7 | 2.1 ppt below the MCL | 25.3 ppt at or above the MCL |
| Norton Water Department MA4218000 | 19,161 | 7 | 8.7 ppt at or above the MCL | 2.0 ppt below the MCL |
| Hanover Water Dept MA4122000 | 14,984 | 7 | 5.4 ppt at or above the MCL | 7.9 ppt at or above the MCL |
Counties with the most systems that found PFAS
- Middlesex County 33 of 54 surveyed systems
- Worcester County 24 of 43 surveyed systems
- Norfolk County 22 of 27 surveyed systems
- Essex County 20 of 32 surveyed systems
- Plymouth County 18 of 24 surveyed systems
- Bristol County 12 of 18 surveyed systems
- Barnstable County 8 of 20 surveyed systems
- Hampshire County 2 of 10 surveyed systems