Chester County tap water
6 of 11 water systems serving Chester County with full PFAS testing averaged above a 2024 federal PFAS level at one or more sampling points.
- 67 community water systems list this county as served; 11 serve 3,300+ people with full PFAS testing.
- 20 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 |
|---|---|---|---|---|
| PA American Royersford | Surface water | 49,508 | Yes | 0 |
| Aqua PA West Chester | Surface water | 48,600 | Yes | 0 |
| PA American Coatesville | Surface water | 36,960 | No | 0 |
| Aqua PA Uwchlan | Purchased surface water | 35,518 | Yes | 0 |
| Phoenixville Water dept | Surface water | 16,599 | No | 1 |
| Downingtown Water Authority | Surface water | 9,900 | No | 0 |
| Aqua PA Friendship | Groundwater | 8,800 | Yes | 0 |
| Aqua PA Spring Run | Purchased surface water | 8,151 | Yes | 0 |
| Kennett Square Mun Water Works | Purchased surface water | 6,328 | Yes | 0 |
| Oxford Borough | Purchased surface water | 5,280 | No | 0 |
| London Grove Twp Mun Auth | Purchased surface water | 4,770 | 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.