We found 20 public water systems in Ohio county (ordered by population size).
| Name | Areas served | Population served | Contaminant count | Violation count |
|---|---|---|---|---|
| Ohio County Water District | County of Ohio | 14,733 | 29 | 74 |
| Beaver Dam Municipal Water & Sewer | County of Ohio | 3,901 | 0 | 33 |
| Hartford Municipal Water Works | County of Ohio | 3,119 | 0 | 121 |
| Rough River Water System Inc | Hartford | 1,740 | 0 | 0 |
| Centertown Water System | County of Ohio | 1,485 | 0 | 22 |
| Perdue Farms Inc | County of Ohio | 1,200 | 0 | 67 |
| Fordsville Water District | County of Ohio | 927 | 0 | 27 |
| Horse Branch Elementary School | Horse Branch | 345 | 0 | 0 |
| Peabody Coal Co/ken 4 | Central City | 310 | 0 | 0 |
| Peabody Coal Co/homestead | Beaver Dam | 180 | 0 | 0 |
| Peabody Coal Co/alston #3 | Centertown | 176 | 0 | 0 |
| Peabody Coal Co/ken Surface | Beaver Dam | 160 | 0 | 0 |
| Peabody Coal Co/alston #4 | Centertown | 147 | 0 | 0 |
| Peabody Coal Co/ken 4n Mine | Beaver Dam | 70 | 0 | 0 |
| Weebro Inc/horton Mine | Hartford | 57 | 0 | 0 |
| Coal Country Truck Stop | County of Ohio | 25 | 0 | 0 |
| Peabody Coal/small House Dock | Centertown | 25 | 0 | 0 |
| Alston Surface Mine | Centertown | 25 | 0 | 0 |
| Big Rivers Electric Corp | County of Ohio | 0 | 0 | 0 |
| Rockport Water Works | Rockport | 0 | 0 | 0 |