All water systems in Ohio
4,165 systems
| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Wapakoneta City PWS Auglaize County |
11,000 | 1 | 1 | |
|
Van Wert City Van Wert County |
10,846 | 4 | 0 | |
|
Earnhart Hill Water District PWS Pickaway County |
10,738 | 1 | 1 | |
|
Vermilion City Erie County |
10,594 | 2 | 1 | |
|
Cambridge, City of Guernsey County |
10,520 | 1 | 1 | |
|
Galion City Crawford County |
10,453 | 2 | 1 | |
|
City of Heath PWS Licking County |
10,310 | 2 | 1 | |
|
Buckeye Water District Ohio River Columbiana County |
10,300 | 3 | 1 | |
|
Mid-Ohio Wsd Chrisman Avenue Wtp Madison County |
10,256 | 3 | 1 | |
|
Trumbull Co. Southeast PWS Trumbull County |
9,931 | 1 | 1 | |
|
Pataskala City Licking County |
9,900 | 1 | 0 | |
|
Little Hocking Water Association, Inc. Washington County |
9,892 | 0 | 0 | |
|
Wyoming City PWS Hamilton County |
9,700 | 1 | 0 | |
|
Jackson, City of Jackson County |
9,691 | 2 | 1 | |
|
Northwestern W and SD Oregon Wtln 200 Wood County |
9,629 | 0 | 0 | |
|
Oakwood City PWS Montgomery County |
9,572 | 0 | 0 | |
|
Reading City PWS Hamilton County |
9,506 | 2 | 2 | |
|
Bellbrook Water Works Greene County |
9,475 | 2 | 1 | |
|
Shelby City Richland County |
9,453 | 1 | 1 | |
|
ST Marys City Auglaize County |
9,356 | 2 | 1 | |
|
Canal Winchester City PWS Franklin County |
9,286 | 1 | 1 | |
|
Twin City Water and Sewer District PWS Tuscarawas County |
9,224 | 1 | 1 | |
|
Louisville City PWS Stark County |
9,186 | 1 | 0 | |
|
Sheffield Lake City PWS Lorain County |
9,108 | 1 | 1 | |
|
Chillicothe Correctional Institution Ross County |
9,000 | 2 | 0 | |
|
Trotwood City PWS Montgomery County |
9,000 | 2 | 1 | |
|
Wright State University Greene County |
8,948 | 1 | 1 | |
|
Guernsey Co. Water Dept. Guernsey County |
8,891 | 2 | 1 | |
|
Clark County Northridge PWS Clark County |
8,874 | 0 | 0 | |
|
Scioto Water Inc.-Rose Hill Scioto County |
8,861 | 2 | 1 | |
|
Napoleon City Henry County |
8,858 | 0 | 0 | |
|
Bryan City PWS Williams County |
8,729 | 1 | 1 | |
|
Portage County Water Resources Portage County |
8,606 | 3 | 2 | |
|
Oberlin Water Department Lorain County |
8,600 | 2 | 1 | |
|
Sanitary District #4 Franklin County |
8,575 | 2 | 1 | |
|
Orrville City PWS Wayne County |
8,452 | 0 | 0 | |
|
Eaton Public Water System Preble County |
8,400 | 0 | 0 | |
|
Hudson City PWS Summit County |
8,385 | 2 | 1 | |
|
Hubbard City PWS Trumbull County |
8,362 | 2 | 1 | |
|
West Carrollton City PWS Montgomery County |
8,361 | 1 | 0 | |
|
Kenton City Hardin County |
8,360 | 3 | 1 | |
|
Trumbull Co. Bazetta/champion Trumbull County |
8,270 | 1 | 1 | |
|
Knox County Water and Wastewater PWS Knox County |
8,250 | 1 | 1 | |
|
Bellevue City Huron County |
8,236 | 2 | 1 | |
|
Aqua Ohio Lawrence County Lawrence County |
8,130 | 1 | 0 | |
|
South Lebanon City PWS Warren County |
7,792 | 3 | 0 | |
|
Canfield City PWS Mahoning County |
7,706 | 1 | 1 | |
|
Rattlesnake PWS Fayette County |
7,685 | 1 | 1 | |
|
Wauseon City PWS Fulton County |
7,568 | 2 | 1 | |
|
Hollywood Gaming @ Mvrc Mahoning County |
7,304 | 0 | 0 |
About this data
Rules violated counts the rules a system was in violation of in the past three years, including monitoring and reporting lapses; one rule can carry several violations. Unresolved is the number of those rules still in violation at EPA's latest data refresh.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Ohio records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet. Retrieved from ECHO on Oct 11, 2026.