Ohio Water Quality
According to EPA Safe Drinking Water Information System (SDWIS), Ohio has 1,089 active community water systems in this extract. PlainEnviro's health-based slice lists 1,500 violation records across 50 systems with at least one such row. These are historical EPA registry counts, not a statewide drinkability score.
Health-based violation records for 1,089 community water systems in Ohio. Source: EPA Safe Drinking Water Information System (SDWIS).
Water Systems with Most Health-Based Records
| # | Water System | Health-Based Records | Health |
|---|---|---|---|
| 1 | MAYSVILLE REGIONAL WATER White Cottage | 72 | Yes |
| 2 | HAMLER VILLAGE Hamler | 70 | Yes |
| 3 | BRUNERSBURG WD - EVANSPORT PWS Defiance | 49 | Yes |
| 4 | AYERSVILLE WATER AND SEWER DISTRICT Defiance | 47 | Yes |
| 5 | HOLGATE VILLAGE Holgate | 43 | Yes |
| 6 | WAUSEON CITY PWS Wauseon, | 34 | Yes |
| 7 | NORTHWESTERN W AND SD - MCCOMB Bowling Green | 34 | Yes |
| 8 | NELSONVILLE PWS Nelsonville | 33 | Yes |
| 9 | GREENLAWN CONDOS Springfield | 30 | Yes |
| 10 | BRUNERSBURG WD - AIRPORT PWS Defiance | 30 | Yes |
| 11 | VAN WERT CITY Van Wert | 29 | Yes |
| 12 | WEST FARMINGTON VILLAGE PWS West Farmington | 28 | Yes |
| 13 | DEFIANCE CITY Defiance | 27 | Yes |
| 14 | NEW LEXINGTON New Lexington | 25 | Yes |
| 15 | SOUTH VIENNA VILLAGE PWS South Vienna | 24 | Yes |
| 16 | NORTHWESTERN W AND SD - CO RD P PWS Bowling Green | 24 | Yes |
| 17 | BYESVILLE Byesville | 22 | Yes |
| 18 | ARCADIA VILLAGE PWS Arcadia | 21 | Yes |
| 19 | HAMDEN VILLAGE PWS Hamden | 21 | Yes |
| 20 | DELTA VILLAGE Delta | 18 | Yes |
| 21 | ROCK CREEK VILLAGE Rock Creek | 17 | Yes |
| 22 | GALION CITY Galion | 17 | Yes |
| 23 | ARCHBOLD VILLAGE Archbold | 16 | Yes |
| 24 | GREEN SPRINGS VILLAGE PWS Green Springs | 16 | Yes |
| 25 | SEBRING VILLAGE PWS Sebring | 15 | Yes |
| 26 | CHRISTI WATER SYSTEM INC Defiance | 14 | Yes |
| 27 | LAGRANGE VILLAGE PWS Lagrange | 14 | Yes |
| 28 | CADIZ VILLAGE PWS Cadiz | 13 | Yes |
| 29 | CLEARFORK MHP Bellville | 13 | Yes |
| 30 | GLANDORF VILLAGE Glandorf | 12 | Yes |
| 31 | ATTICA VILLAGE Attica | 11 | Yes |
| 32 | BLUFFTON VILLAGE Bluffton | 10 | Yes |
| 33 | MANSFIELD CITY Mansfield | 10 | Yes |
| 34 | NORTHEAST WATER SYSTEM Wauseon | 9 | Yes |
| 35 | ALLIANCE CITY PWS Alliance | 9 | Yes |
| 36 | NORTHWESTERN W AND SD - OREGON WTLN 200 Bowling Green | 9 | Yes |
| 37 | CHOCTAW UTILITIES, INC. London | 8 | Yes |
| 38 | PUT-IN-BAY VILLAGE Put-in-bay | 8 | Yes |
| 39 | OAKWOOD VILLAGE PWS Oakwood | 8 | Yes |
| 40 | HICKORY MANOR MOBILE HOME PARK Cincinnati | 7 | Yes |
| 41 | ST. CLAIRSVILLE, CITY OF PWS St. Clairsville | 7 | Yes |
| 42 | PAULDING VILLAGE PWS Paulding | 7 | Yes |
| 43 | HILLSIDE MHP Port Clinton | 7 | Yes |
| 44 | CONCORD CARE CENTER OF HARTFORD Fowler | 7 | Yes |
| 45 | WESTVIEW MHP Chardon | 7 | Yes |
| 46 | LIMA CITY Lima | 6 | Yes |
| 47 | WAYNOKA REGIONAL WATER AND SEWER DIST Sardinia | 6 | Yes |
| 48 | SPRING VALLEY MOBILE HOME PARK Galion | 6 | Yes |
| 49 | BRUNERSBURG WD - BRUNERSBURG PWS Defiance | 6 | Yes |
| 50 | CHARDON WOODS OF JOURNEY Chardon | 6 | Yes |
Most Common Contaminants in Ohio
| Contaminant | Violations | Systems Affected |
|---|---|---|
| TTHM | 746 | 67 |
| LEAD AND COPPER RULE REVISIONS | 177 | 131 |
| Lead and Copper Rule | 177 | 69 |
| Total Haloacetic Acids (HAA5) | 97 | 13 |
| Groundwater Rule | 70 | 31 |
| Arsenic | 64 | 5 |
| Interim Enhanced Surface Water Treatment Rule | 60 | 19 |
| Long Term 2 Enhanced Surface Water Treatment Rule | 29 | 18 |
| Surface Water Treatment Rule | 22 | 9 |
| Revised Total Coliform Rule | 21 | 11 |
| CARBON, TOTAL | 19 | 1 |
| Stage 1 Disinfectants and Disinfection Byproducts Rule | 10 | 7 |
| Nitrate | 4 | 2 |
| Chlorite | 2 | 1 |
| Coliform (TCR) | 1 | 1 |
Cities with Water Quality Issues
Explore More
About This Data
Water quality data is from the EPA Safe Drinking Water Information System (SDWIS). Health-based violations include Maximum Contaminant Level (MCL) and Treatment Technique (TT) violations. Only community water systems (CWS) in Ohio are included.
Source: U.S. Environmental Protection Agency, SDWIS Federal Reporting Services
Read our methodology - how this data is sourced, computed, and verified.