Ohio tap water
35 of 327 Ohio water systems with full PFAS testing (11%) averaged above a 2024 federal PFAS level at one or more sampling points.
- 1,122 active community water systems in the EPA file; 304 serve 3,300+ people and have a full PFAS set.
- 222 systems had at least one health-based violation since 2021-10-26.
- 0 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 |
|---|---|---|---|
| Columbus Public Water System | 1,309,468 | No | 0 |
| Cleveland Public Water System | 1,308,955 | No | 0 |
| Cincinnati Public Water System | 800,000 | Yes, at one or more sampling points | 0 |
| Toledo City of | 360,000 | No | 1 |
| Akron City PWS | 280,000 | No | 1 |
| Montgomery County Water Services 1 PWS | 150,207 | Yes, at one or more sampling points | 0 |
| Del-Co Water Company, Inc. | 150,000 | No | 0 |
| Dayton Public Water System | 141,407 | Yes, at one or more sampling points | 0 |
Counties
Montgomery County14 systems with full PFAS testingFranklin County11 systems with full PFAS testingLorain County11 systems with full PFAS testing
All 37 utilities with a page in Ohio
- Akron City PWS 280,000
- Aqua Ohio - Marion 47,102
- Aqua Ohio - Massillon PWS 95,636
- Aqua Ohio - Mentor 74,500
- Aqua Ohio - Struthers 58,551
- Butler CO. Water District 2 PWS 116,572
- Canton Public Water System 107,113
- Cincinnati Public Water System 800,000
- Clermont Public Water System 133,059
- Cleveland Public Water System 1,308,955
- Columbus Public Water System 1,309,468
- Cuyahoga Falls City PWS 51,114
- Dayton Public Water System 141,407
- Del-Co Water Company, Inc. 150,000
- Delaware City PWS 43,895
- Elyria Water department 68,000
- Fairfield City PWS 44,907
- Findlay City PWS 54,040
- Greene Co.-Northwest Reg Water 41,895
- Hamilton Public Water System 62,447
- Huber Heights Public Water System 43,439
- Lake County West Water Subdistrict 78,379
- Lakewood City PWS 50,942
- Lima City 65,619
- Lorain City PWS 64,152
- Mansfield City 51,000
- Medina Co/Northwest PWS 46,324
- Middletown City PWS 51,229
- Montgomery County Water Services 1 PWS 150,207
- Montgomery County Water Services 2 PWS 83,033
- Newark City PWS 49,934
- Rural Lorain CO. Water A 73,125
- Southwest Regional Water District 42,856
- Springfield City PWS 60,680
- Toledo City of 360,000
- Warren City PWS 49,130
- Warren County 99,000
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.