Collin County tap water
0 of 22 water systems serving Collin County with full PFAS testing averaged above a 2024 federal PFAS level at one or more sampling points.
- 35 community water systems list this county as served; 22 serve 3,300+ people with full PFAS testing.
- 6 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 |
|---|---|---|---|---|
| City of Plano | Purchased surface water | 292,059 | No | 0 |
| City of Frisco | Purchased surface water | 231,910 | No | 0 |
| City of Mckinney | Purchased surface water | 224,043 | No | 0 |
| City of Allen | Purchased surface water | 113,746 | No | 0 |
| City of Wylie | Purchased surface water | 48,393 | No | 0 |
| Town of Prosper | Purchased surface water | 42,598 | No | 0 |
| City of Princeton | Purchased surface water | 37,019 | No | 0 |
| City of Melissa | Purchased surface water | 26,234 | No | 0 |
| Culleoka Wsc | Purchased surface water | 24,615 | No | 0 |
| City of Anna | Purchased surface water | 23,960 | No | 1 |
| City of Murphy | Purchased surface water | 21,082 | No | 0 |
| East Fork Sud | Purchased surface water | 17,589 | 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.