Middlesex County tap water
16 of 54 water systems serving Middlesex County with full PFAS testing averaged above a 2024 federal PFAS level at one or more sampling points.
- 98 community water systems list this county as served; 53 serve 3,300+ people with full PFAS testing.
- 10 had a health-based violation since 2021-10-26.
Largest systems serving this county
| System | Source | People served (whole system) | PFAS above a 2024 level? | Violations since 2021-10-26 |
|---|---|---|---|---|
| Lowell Regional Water Utility | Surface water | 120,418 | No | 0 |
| Cambridge Water department | Surface water | 118,214 | No | 0 |
| Newton Water dept. (Mwra) | Purchased surface water | 88,931 | No | 0 |
| Somerville Water dept. (Mwra) | Purchased surface water | 81,045 | No | 0 |
| Framingham Water dept. (Mwra) | Purchased surface water | 72,362 | No | 0 |
| Malden Water Division (Mwra) | Purchased surface water | 66,263 | No | 0 |
| Waltham Water department | Purchased surface water | 65,218 | No | 0 |
| Medford Water dept. (Mwra) | Purchased surface water | 61,700 | No | 2 |
| Everett Water dept. (Mwra) | Purchased surface water | 49,075 | No | 0 |
| Arlington Water dept. (Mwra) | Purchased surface water | 46,308 | No | 0 |
| Billerica Water Works | Surface water | 42,119 | No | 3 |
| Marlborough Dpw Water Div. (Mwra) | Purchased surface water | 41,799 | No | 0 |
Which one is yours? A county usually has several utilities. Your bill or your utility's annual water-quality report names yours. Population is for the whole system, which can cross county lines.
Not medical or legal advice. UCMR 5 results are screening data, not compliance determinations.
Sources and freshness
Public-water-system facts, violations and lead/copper results: EPA ECHO SDWA download (SDWIS snapshot 2026-10-13). PFAS and lithium results: EPA UCMR 5 final data (sampling 2023–2025). Both are U.S. government works, downloaded 2026-10-26. Numbers are computed by the published method; the same fields are in the open data files.