PFAS detected in Massachusetts water systems

EPA UCMR 5 monitoring (2023–2025) detected PFOA or PFOS at or above 6 parts per trillion in these 43 large Massachusetts public water systems, each serving more than 10,000 people. Select a system to see exactly what was detected and the certified filters that reduce it.

Massachusetts systems, highest detections first

Water system PFOA (ppt) PFOS (ppt) vs. 4 ppt reference
Raynham Center Water District 92 — 23×
Dartmouth Water Division 4.2 50.6 12.7×
Natick Water Department 14.3 37.3 9.3×
Duxbury Water Department 7.5 35 8.8×
Norwell Water Department 9.9 18.4 4.6×
Easton Water Div 9.9 16.3 4.1×
Sharon Water Dept 8.1 15 3.8×
Acton Water Supply District 13.4 4.9 3.4×
Randolph Water Department 7.3 13 3.3×
Abington/Rockland Joint WTR. Works 12 7 3×
Attleboro Water Dept 6.6 12 3×
Holbrook Public Works Dept 7 11.9 3×
Hanover Water Dept, MA 8.9 11.4 2.9×
Middleborough Water Supply 11 5 2.8×
Bridgewater Water Department 9 7 2.3×
North Attleboro Water Dept 9 8 2.3×
Sudbury Water District 9 — 2.3×
Wayland Water Department 9 4 2.3×
Chelmsford Water District 8.9 7.2 2.2×
Norton Water Department 8.8 4 2.2×
Westford Water Department 8.6 4.4 2.1×
Braintree Water and Sewer Dept. 5.3 8.5 2.1×
Woburn Water Dept. 8.4 6.9 2.1×
Westborough Water Department 5.8 7.5 1.9×
Ipswich Dpu Water Dept 7.3 — 1.8×
Stoughton Water Department 7.3 6.3 1.8×
Maynard DPW, Water Division 7.1 4.2 1.8×
Milford Water Company 7.1 6.6 1.8×
Marshfield Water Department 7 4.6 1.8×
Medfield Water Dept. 7 6.7 1.8×
Peabody Water Dept. 7 — 1.8×
Grafton Water District 6.9 6.9 1.7×
Wakefield Water Dept 6.9 — 1.7×
Foxboro Water Department 6.3 6.7 1.7×
Uxbridge DPW, Water Division — 6.7 1.7×
Wellesley Water Division 6.3 6.6 1.6×
Dedham Westwood Water Dist. 6.5 5.1 1.6×
Holliston Water Department 5.3 6.5 1.6×
Weir River Water System 6.4 — 1.6×
Mansfield Water Division 4.3 6.2 1.6×
Dracut Water Supply District 6.1 — 1.5×
Concord Water Dept, MA 6 — 1.5×
Salisbury Water Department 6 — 1.5×

Highest single EPA UCMR 5 detections (2023–2025), in parts per trillion. The last column is the multiple of the 4 ppt federal reference level for PFOA/PFOS — shown as context only, not a compliance or health determination. — means the compound was not detected at or above 6 ppt.

Not sure what's in your own water? Test it first, then run the selector for a recommendation matched to your home, or read what PFAS is and how it's removed.