State drinking water records
Ohio drinking water systems
1,127 community water systems serve Ohio and are listed below under 88 counties and on the pages of 979 cities and towns. Their own population figures add up to 10,455,228 people, a sum that counts people twice where one system sells water to another.
274 of them (24%) had at least one health-based violation in the last 10 years. 810 systems still have one unresolved.
863 rely mainly on groundwater and 264 on surface water, counting water bought from other systems.
1,068 systems filed a lead service line inventory listing 265,276 lead lines, 56,048 galvanized lines that must be replaced and 869,730 lines of unknown material.
77 systems are placed by the county their records name: EPA has no service area map for 60 of them, and 17 have one that does not line up with their own records.
- Community water systems
- 1,127
- People served, sum of each system's own figure
- 10,455,228
- Systems with a health-based violation, last 10 years
- 274
- Systems with one unresolved
- 810
- Lead service lines in inventories
- 265,276
Counties
88 countiesEach county counts the systems whose service area map reaches it. Systems placed only by a mailing address are listed on the county pages but not counted here.
| County | Systems | People served | With a health-based violation, 10 years | With one unresolved |
|---|---|---|---|---|
| Adams County | 6 | 31,497 | 2 | 5 |
| Allen County | 8 | 84,476 | 1 | 5 |
| Ashland County | 9 | 25,657 | 1 | 5 |
| Ashtabula County | 10 | 65,300 | 2 | 8 |
| Athens County | 13 | 75,476 | 4 | 13 |
| Auglaize County | 8 | 30,647 | 2 | 7 |
| Belmont County | 16 | 64,918 | 5 | 16 |
| Brown County | 8 | 50,044 | 3 | 6 |
| Butler County | 12 | 386,950 | 0 | 7 |
| Carroll County | 5 | 6,881 | 2 | 5 |
| Champaign County | 11 | 18,684 | 1 | 7 |
| Clark County | 25 | 91,841 | 4 | 19 |
| Clermont County | 10 | 225,628 | 3 | 10 |
| Clinton County | 6 | 60,518 | 1 | 4 |
| Columbiana County | 16 | 59,216 | 2 | 13 |
| Coshocton County | 7 | 14,604 | 2 | 6 |
| Crawford County | 4 | 27,708 | 2 | 3 |
| Cuyahoga County | 6 | 1,396,882 | 1 | 4 |
| Darke County | 12 | 25,498 | 4 | 10 |
| Defiance County | 8 | 25,197 | 6 | 4 |
| Delaware County | 4 | 234,093 | 0 | 2 |
| Erie County | 8 | 55,550 | 1 | 5 |
| Fairfield County | 22 | 96,469 | 3 | 16 |
| Fayette County | 6 | 23,524 | 1 | 5 |
| Franklin County | 30 | 1,495,860 | 7 | 17 |
| Fulton County | 9 | 25,128 | 6 | 6 |
| Gallia County | 3 | 28,959 | 0 | 3 |
| Geauga County | 30 | 21,982 | 7 | 14 |
| Greene County | 17 | 169,040 | 2 | 9 |
| Guernsey County | 6 | 28,937 | 3 | 5 |
| Hamilton County | 10 | 837,421 | 0 | 6 |
| Hancock County | 10 | 76,600 | 2 | 6 |
| Hardin County | 8 | 18,228 | 4 | 6 |
| Harrison County | 14 | 11,224 | 5 | 13 |
| Henry County | 10 | 15,008 | 4 | 4 |
| Highland County | 7 | 44,693 | 0 | 5 |
| Hocking County | 7 | 9,077 | 3 | 6 |
| Holmes County | 12 | 12,007 | 5 | 10 |
| Huron County | 14 | 62,869 | 5 | 9 |
| Jackson County | 5 | 20,474 | 3 | 5 |
| Jefferson County | 16 | 55,260 | 9 | 15 |
| Knox County | 9 | 31,438 | 0 | 5 |
| Lake County | 5 | 228,443 | 1 | 1 |
| Lawrence County | 6 | 61,075 | 2 | 3 |
| Licking County | 23 | 150,528 | 4 | 19 |
| Logan County | 16 | 22,341 | 6 | 14 |
| Lorain County | 16 | 339,674 | 3 | 12 |
| Lucas County | 8 | 427,981 | 2 | 7 |
| Madison County | 17 | 31,807 | 5 | 14 |
| Mahoning County | 8 | 206,420 | 2 | 6 |
| Marion County | 4 | 47,505 | 1 | 1 |
| Medina County | 9 | 107,940 | 1 | 7 |
| Meigs County | 6 | 28,497 | 4 | 6 |
| Mercer County | 9 | 22,904 | 1 | 7 |
| Miami County | 17 | 90,746 | 2 | 14 |
| Monroe County | 6 | 13,352 | 2 | 4 |
| Montgomery County | 21 | 509,580 | 5 | 16 |
| Morgan County | 8 | 5,135 | 2 | 7 |
| Morrow County | 6 | 157,576 | 0 | 2 |
| Muskingum County | 11 | 69,664 | 3 | 7 |
| Noble County | 7 | 11,868 | 2 | 6 |
| Ottawa County | 10 | 44,171 | 4 | 9 |
| Paulding County | 6 | 7,711 | 2 | 5 |
| Perry County | 19 | 25,929 | 5 | 16 |
| Pickaway County | 20 | 41,167 | 7 | 15 |
| Pike County | 6 | 23,815 | 0 | 5 |
| Portage County | 31 | 100,247 | 5 | 17 |
| Preble County | 12 | 21,241 | 3 | 9 |
| Putnam County | 10 | 15,065 | 5 | 6 |
| Richland County | 46 | 90,257 | 4 | 24 |
| Ross County | 7 | 61,188 | 2 | 6 |
| Sandusky County | 9 | 39,889 | 4 | 7 |
| Scioto County | 17 | 83,235 | 0 | 16 |
| Seneca County | 11 | 39,207 | 6 | 8 |
| Shelby County | 15 | 29,040 | 2 | 11 |
| Stark County | 28 | 286,392 | 6 | 15 |
| Summit County | 24 | 438,148 | 6 | 17 |
| Trumbull County | 26 | 144,504 | 6 | 21 |
| Tuscarawas County | 14 | 62,233 | 2 | 13 |
| Union County | 5 | 33,246 | 1 | 3 |
| Van Wert County | 6 | 20,733 | 2 | 6 |
| Vinton County | 3 | 3,250 | 2 | 3 |
| Warren County | 16 | 209,733 | 4 | 12 |
| Washington County | 15 | 60,927 | 3 | 13 |
| Wayne County | 30 | 58,424 | 6 | 18 |
| Williams County | 12 | 17,461 | 2 | 9 |
| Wood County | 20 | 109,532 | 4 | 11 |
| Wyandot County | 4 | 12,048 | 0 | 3 |
Largest systems
| System | Main county | People served | Main source | Health-based violations, 10 years | Unresolved | Lead lines |
|---|---|---|---|---|---|---|
| Cleveland Public Water System | Cuyahoga County | 1,308,955 | Surface water | 0 | 0 | 144,193 |
| Columbus Public Water System | Franklin County | 1,305,946 | Surface water | 0 | 0 | 25,155 |
| Cincinnati Public Water System | Hamilton County | 750,200 | Surface water | 0 | 0 | 34,673 |
| City of Toledo | Lucas County | 360,000 | Surface water | 1 | 1 | 1,944 |
| Akron City PWS | Summit County | 280,000 | Surface water | 1 | 0 | 1,683 |
| Montgomery County Water Services 1 PWS | Montgomery County | 150,207 | Purchased surface water | 2 | 0 | 370 |
| Del-Co Water Company, Inc. | Delaware County and 1 other county | 150,000 | Surface water | 0 | 0 | 9 |
| Dayton Public Water System | Montgomery County | 141,407 | Surface water | 0 | 0 | 9,393 |
| Clermont Public Water System | Clermont County | 133,059 | Surface water | 1 | 2 | 0 |
| Youngstown City PWS | Mahoning County | 130,530 | Purchased surface water | 0 | 1 | 736 |
| Butler Co. Water District 2 PWS | Butler County | 116,572 | Purchased surface water | 0 | 0 | 0 |
| Canton Public Water System | Stark County | 107,113 | Groundwater | 0 | 1 | 0 |
| Aqua Ohio - Massillon PWS | Stark County | 95,636 | Groundwater | 0 | 1 | 0 |
| Montgomery County Water Services 2 PWS | Montgomery County | 83,033 | Purchased surface water | 2 | 0 | 653 |
| Warren County | Warren County | 81,975 | Groundwater | 0 | 1 | 0 |
Systems with unresolved health-based violations
810 systemsThe 100 with the most unresolved violations are listed. The county pages list the other 710.
| System | Main county | People served | Main source | Health-based violations, 10 years | Unresolved | Lead lines |
|---|---|---|---|---|---|---|
| Pomeroy Village PWS | Meigs County | 1,800 | Groundwater | 1 | 12 | No inventory |
| Warren Water Authority | Jefferson County | 481 | Purchased groundwater | 2 | 10 | No inventory |
| Ironton | Lawrence County | 11,129 | Surface water | 1 | 9 | 0 |
| Manchester Village | Adams County | 2,043 | Groundwater | 1 | 9 | No inventory |
| New Paris Village PWS | Preble County | 1,681 | Groundwater | 1 | 9 | No inventory |
| Freeport Village PWS | Harrison County | 400 | Groundwater | 0 | 9 | 0 |
| South Solon Village PWS | Madison County | 395 | Groundwater | 1 | 9 | 0 |
| Holloway Public Water System | Belmont County | 360 | Groundwater | 1 | 9 | No inventory |
| Apollo Mobile Home Park | Sandusky County | 100 | Groundwater | 1 | 9 | No inventory |
| Frontier Campground | Warren County | 100 | Groundwater | 2 | 9 | No inventory |
| Kingston Village PWS | Ross County | 1,032 | Purchased groundwater | 1 | 8 | 0 |
| Yorkville Village PWS | Jefferson County and 1 other county | 1,019 | Purchased groundwater | 1 | 8 | 0 |
| Alger Village PWS | Hardin County | 943 | Groundwater | 2 | 8 | 0 |
| Waterford Water/Sewer Association | Washington County | 770 | Groundwater | 1 | 8 | No inventory |
| Carrollton Village | Carroll County | 3,055 | Groundwater | 1 | 7 | No inventory |
| Columbus Grove Village | Putnam County | 2,137 | Groundwater | 2 | 7 | 0 |
| Brilliant Water and Sewer | Jefferson County | 2,000 | Groundwater | 1 | 7 | 0 |
| Coolville Village PWS | Athens County | 859 | Purchased groundwater | 1 | 7 | No inventory |
| Greenlawn Estates MHP | Muskingum County | 480 | Purchased groundwater | 0 | 7 | 0 |
| Mount Eaton Village PWS | Wayne County | 425 | Groundwater | 1 | 7 | 0 |
| Shelby County Water and Sewer PWS | Shelby County | 375 | Groundwater | 0 | 7 | 0 |
| Rushville Village PWS | Fairfield County | 357 | Purchased groundwater | 1 | 7 | 0 |
| Wilmot Village PWS | Stark County | 325 | Groundwater | 2 | 7 | 0 |
| Buckeye Water District - Ohio River | Columbiana County | 10,300 | Surface water | 1 | 6 | No inventory |
| Reading City PWS | Hamilton County | 9,506 | Purchased surface water | 0 | 6 | 259 |
| Lexington Village | Richland County | 4,825 | Groundwater | 0 | 6 | 0 |
| Hicksville Village | Defiance County | 3,600 | Groundwater | 0 | 6 | 1 |
| Bridgeport Public Water System | Belmont County | 2,830 | Purchased groundwater | 0 | 6 | 14 |
| Bethel Village PWS | Clermont County | 2,620 | Purchased groundwater | 1 | 6 | No inventory |
| Reno Water and Sewer 1 | Washington County | 2,189 | Purchased groundwater | 0 | 6 | 0 |
| Pure Water Corporation | Noble County | 1,989 | Purchased surface water | 2 | 6 | No inventory |
| McArthur Village PWS | Vinton County | 1,920 | Groundwater | 0 | 6 | 0 |
| Lewisburg Village PWS | Preble County | 1,800 | Groundwater | 0 | 6 | 0 |
| Windham Village PWS | Portage County | 1,777 | Groundwater | 0 | 6 | 0 |
| Union City Village PWS | Darke County | 1,650 | Purchased groundwater | 0 | 6 | 14 |
| Timberlake Water System | Franklin County | 1,600 | Groundwater | 1 | 6 | 0 |
| Otterbein-Lebanon Retreat Center | Warren County | 1,541 | Groundwater | 1 | 6 | 0 |
| Bremen Village | Fairfield County | 1,425 | Groundwater | 0 | 6 | No inventory |
| West Salem Village PWS | Wayne County | 1,410 | Groundwater | 0 | 6 | 0 |
| Jeffersonville Village PWS | Fayette County | 1,356 | Groundwater | 1 | 6 | 0 |
| Malvern Village PWS | Carroll County | 1,200 | Groundwater | 2 | 6 | 1 |
| Andover Village PWS | Ashtabula County | 1,019 | Groundwater | 0 | 6 | 0 |
| West Farmington Village PWS | Trumbull County | 908 | Purchased surface water | 14 | 6 | 0 |
| Ohio City Village PWS | Van Wert County | 705 | Groundwater | 0 | 6 | 0 |
| Pine Ridge MHP | Lorain County | 570 | Purchased surface water | 0 | 6 | 0 |
| Florida Village | Henry County | 450 | Purchased surface water | 0 | 6 | 0 |
| Reno Water and Sewer - Kardex | Washington County | 446 | Purchased groundwater | 0 | 6 | 0 |
| Fair Haven Shelby County Home | Shelby County | 290 | Groundwater | 0 | 6 | 0 |
| Amesville Public Water System | Athens County | 255 | Groundwater | 0 | 6 | 0 |
| Midway Mobile Homes LLC | Trumbull County | 213 | Groundwater | 0 | 6 | 0 |
| Holly Hill Health Care Residence | Geauga County | 202 | Groundwater | 1 | 6 | 0 |
| Woodbury Apartments PWS | Clark County | 120 | Groundwater | 0 | 6 | 0 |
| Grand Lake Estates | Mercer County | 103 | Groundwater | 0 | 6 | 0 |
| Green Acres MHP | Ashland County | 80 | Groundwater | 0 | 6 | 0 |
| North Ridgeville City PWS | Lorain County | 29,465 | Purchased surface water | 0 | 5 | 0 |
| Pike Water, Inc.-Plant PWS | Pike County | 15,487 | Groundwater | 0 | 5 | 0 |
| Bellefontaine City PWS | Logan County | 13,249 | Groundwater | 0 | 5 | 300 |
| Trotwood City PWS | Montgomery County | 9,000 | Purchased surface water | 0 | 5 | 3 |
| Chillicothe Correctional Institution | Ross County | 9,000 | Groundwater | 1 | 5 | 0 |
| Odrc-Pickaway Correction PWS | Franklin County and 1 other county | 3,376 | Groundwater | 1 | 5 | 0 |
| Morrow Village PWS | Warren County | 3,360 | Groundwater | 1 | 5 | No inventory |
| Genoa Village | Ottawa County | 3,110 | Purchased surface water | 1 | 5 | 0 |
| Switzerland of Ohio Water | Monroe County | 2,500 | Purchased surface water | 0 | 5 | 0 |
| Middleport Village PWS | Meigs County | 2,446 | Groundwater | 1 | 5 | No inventory |
| Piketon Village PWS | Pike County | 2,181 | Groundwater | 0 | 5 | 0 |
| Aqua Ohio - Midvale | Tuscarawas County | 2,147 | Groundwater | 1 | 5 | 0 |
| Mount Sterling Village PWS | Madison County | 2,059 | Groundwater | 0 | 5 | 0 |
| Beverly Village PWS | Washington County | 1,900 | Groundwater | 0 | 5 | 0 |
| Reno Water and Sewer 2 | Washington County | 1,520 | Purchased groundwater | 0 | 5 | 0 |
| Bethesda Public Water System | Belmont County | 1,382 | Purchased groundwater | 1 | 5 | 0 |
| Syracuse Village PWS | Meigs County | 826 | Groundwater | 1 | 5 | 0 |
| Coalton | Jackson County | 663 | Purchased groundwater | 1 | 5 | No inventory |
| Lucas Village | Richland County | 620 | Groundwater | 0 | 5 | 0 |
| Laurelville, VLG of | Hocking County and 1 other county | 586 | Groundwater | 1 | 5 | 0 |
| Rushsylvania Village PWS | Logan County | 551 | Groundwater | 1 | 5 | 0 |
| Republic Village | Seneca County | 550 | Groundwater | 0 | 5 | 0 |
| Phillipsburg Village PWS | Montgomery County | 490 | Groundwater | 0 | 5 | 0 |
| Jacksonville Village PWS | Athens County | 481 | Purchased groundwater | 0 | 5 | 0 |
| Ohio Living Dorothy Love PWS | Shelby County | 471 | Groundwater | 0 | 5 | 0 |
| Mountainview Mobile Village | Logan County | 300 | Groundwater | 1 | 5 | No inventory |
| Fostoria Mobile Estates | Seneca County | 281 | Groundwater | 1 | 5 | 0 |
| Dunfalls Association, Inc. | Muskingum County | 266 | Purchased groundwater | 1 | 5 | 0 |
| Country Haven MHP PWS | Clark County | 234 | Groundwater | 0 | 5 | 0 |
| Wayne County Care Center | Wayne County | 225 | Groundwater | 0 | 5 | 0 |
| Nashville Village PWS | Holmes County | 197 | Groundwater | 2 | 5 | 0 |
| Wayne MHP LP | Warren County | 175 | Groundwater | 1 | 5 | No inventory |
| Quarry Lakes MHP LLC | Montgomery County | 141 | Groundwater | 2 | 5 | 0 |
| Hidden Valley MHP PWS | Shelby County | 85 | Groundwater | 1 | 5 | 0 |
| Woodland Hills Estates II | Morgan County | 70 | Groundwater | 1 | 5 | 0 |
| Lakeside Estates Mobile Home Park | Auglaize County | 45 | Groundwater | 0 | 5 | 0 |
| Camp Wissalohican Water System | Madison County | 45 | Groundwater | 0 | 5 | 0 |
| Cottonwood Enterprises | Logan County | 30 | Groundwater | 1 | 5 | No inventory |
| Piqua City PWS | Miami County | 20,354 | Surface water | 0 | 4 | 600 |
| Jackson Co. Water Company-WTP | Jackson County | 15,984 | Groundwater | 0 | 4 | 0 |
| Jefferson Co W and S District - M | Jefferson County | 13,983 | Purchased surface water | 0 | 4 | 0 |
| Kenton City | Hardin County | 8,360 | Groundwater | 1 | 4 | 1 |
| Nelsonville PWS | Athens County | 6,656 | Groundwater | 13 | 4 | 0 |
| Rittman City PWS | Wayne County | 6,491 | Groundwater | 0 | 4 | 3 |
| Cleves Village PWS | Hamilton County | 6,000 | Groundwater | 0 | 4 | 0 |
| Mid-Ohio WSD Plain City WTP | Madison County and 1 other county | 4,467 | Groundwater | 0 | 4 | 180 |
Counties come from the counties EPA lists each system serving, matched to 2024 Census counties; where EPA lists none, from the county coded in the system's ID, its service area map, or its mailing address. A county holding at least a fifth of a system's service area map is added when at least a fifth of that map lies in those counties. Towns are the ones EPA lists and the Census places such a map covers, always inside those counties. In New England, where EPA's town names a whole Town, it is not matched to the village of the same name. A system is not listed in a county holding less than a fifth of its map, or in a county or town its map reaches when the map lies mostly outside the counties EPA lists, so a page can leave out a system that serves part of the area. Methodology and limitations