Connecticut tap water
28 of 60 Connecticut water systems with full PFAS testing (47%) averaged above a 2024 federal PFAS level at one or more sampling points.
- 474 active community water systems in the EPA file; 56 serve 3,300+ people and have a full PFAS set.
- 161 systems had at least one health-based violation since 2021-10-26.
- 1 systems report a lead 90th percentile above 15 ppb (some results are old; check each system page).
Largest systems
| System | People served | PFAS above a 2024 level? | Health-based violations since 2021-10-26 |
|---|---|---|---|
| Regional Water Authority | 418,900 | Yes, at one or more sampling points | 0 |
| Metropolitan District Commission | 390,887 | No | 0 |
| Aquarion-Eastern Fairfield County | 351,756 | No | 0 |
| Aquarion-Stamford | 119,214 | No | 0 |
| Waterbury Water department | 107,271 | No | 0 |
| Ctwc - Northern Reg-Western System | 101,313 | Yes, at one or more sampling points | 0 |
| New Britain Water department | 73,534 | No | 0 |
| Danbury Water department | 62,055 | Yes, at one or more sampling points | 0 |
Counties
All 14 utilities with a page in Connecticut
- Aquarion-Eastern Fairfield County 351,756
- Aquarion-Greenwich 53,297
- Aquarion-Stamford 119,214
- Bristol Water department 52,079
- Ctwc - Northern Reg-Western System 101,313
- Danbury Water department 62,055
- Manchester Water department 51,198
- Meriden Water Division 58,441
- Metropolitan District Commission 390,887
- New Britain Water department 73,534
- Regional Water Authority 418,900
- South Norwalk Electric & Water 42,000
- Southington Water department 43,069
- Waterbury Water department 107,271
Why not "the state's water quality"? You drink from one utility, not a state. Rollups count systems, not people, so one large utility counts the same as a small one. Use the system pages for your actual water.
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.