263 public water systems in Massachusetts were sampled in EPA's UCMR 5 programme (2023–2025); we show six PFAS and lithium. Read 2026-10-31.
106 of 263 systems had at least one sample above a 2024 federal limit; 122 had at least one PFAS found above the reporting level; 141 had none found above the reporting level.
A single sample above a 2024 limit is a measurement, not a violation. Compliance is judged on running yearly averages, and water systems have until 2029 to meet the limits. On 20 May 2026 EPA proposed giving qualifying systems until 2031 for PFOA and PFOS and removing the limits for PFHxS, PFNA and HFPO-DA; those proposals were not final when we last checked (5 Nov 2026). Counts are per system, not per person; population figures are available only for systems serving more than 25,000 people (about 5,274,141 people across those systems here). UCMR 5 was a one-time national monitoring programme (2023–2025). The results are a snapshot at the system's entry points or taps on the sample dates, not a continuous measurement and not a compliance record.
| System | People served | UCMR 5 result |
|---|---|---|
| Boston Boston Water and Sewer Commission (Mwra) | 675,647 | None detected (below the reporting level) |
Pages for these are being added in stages. The data for all 263 systems is in the public dataset.
| System | People served | UCMR 5 result |
|---|---|---|
| Worcester Dpwp, Water Supply Division Worcester Dpwp, Water Supply Division | 206,518 | None detected (below the reporting level) |
| Springfield Water and Sewer Commission Springfield Water and Sewer Commission | 169,170 | None detected (below the reporting level) |
| Lowell Regional Water Utility Lowell Regional Water Utility | 120,418 | Above the 2024 limit in at least one sample |
| Cambridge Water Department Cambridge Water Department | 118,214 | Above the 2024 limit in at least one sample |
| Quincy Water Dept. (Mwra) Quincy Water Dept. (Mwra) | 106,000 | None detected (below the reporting level) |
| Brockton Water Department Brockton Water Department | 105,788 | None detected (below the reporting level) |
| Inima Usa / Aquaria Llc Inima Usa / Aquaria Llc | 105,643 | None detected (below the reporting level) |
| Lynn Water and Sewer Comm Lynn Water and Sewer Comm | 101,253 | Above the 2024 limit in at least one sample |
| City of New Bedford Dpi City of New Bedford Dpi | 101,079 | None detected (below the reporting level) |
| Falmouth Water Dept Falmouth Water Dept | 97,551 | None detected (below the reporting level) |
| Fall River Water Department Fall River Water Department | 94,000 | None detected (below the reporting level) |
| Lawrence Water Works Lawrence Water Works | 89,143 | None detected (below the reporting level) |
| Newton Water Dept. (Mwra) Newton Water Dept. (Mwra) | 88,931 | None detected (below the reporting level) |
| Somerville Water Dept. (Mwra) Somerville Water Dept. (Mwra) | 81,045 | None detected (below the reporting level) |
| Framingham Water Dept. (Mwra) Framingham Water Dept. (Mwra) | 72,362 | None detected (below the reporting level) |
| Malden Water Division (Mwra) Malden Water Division (Mwra) | 66,263 | None detected (below the reporting level) |
| Waltham Water Department Waltham Water Department | 65,218 | None detected (below the reporting level) |
| Dennis Water District Dennis Water District | 65,000 | None detected (below the reporting level) |
| Brookline Water and Sewer Division Brookline Water and Sewer Division | 63,191 | None detected (below the reporting level) |
| Revere Water Division (Mwra) Revere Water Division (Mwra) | 62,186 | None detected (below the reporting level) |
| Taunton Water Division Taunton Water Division | 62,165 | None detected (below the reporting level) |
| Medford Water Dept. (Mwra) Medford Water Dept. (Mwra) | 61,700 | None detected (below the reporting level) |
| Haverhill Water Dept Haverhill Water Dept | 61,277 | None detected (below the reporting level) |
| Weymouth Water Department Weymouth Water Department | 57,871 | None detected (below the reporting level) |
| Upper Cape Regional Water Cooperative Upper Cape Regional Water Cooperative | 56,250 | None detected (below the reporting level) |