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AquaCensus

Ohio public water systems

4,028 active systems regulated under the Safe Drinking Water Act, serving a reported 11.1M people across 134 counties.

Dataset updated . Source: EPA SDWIS/ECHO, refreshed quarterly.

Active systems

4,028

Population served

11.1M

Community systems

1,070

Groundwater share

92.5%

System types in Ohio

1,070

Community water system

572

Non-transient non-community water system

2,386

Transient non-community water system

Largest water systems in Ohio

The largest active public water systems in Ohio by population served
#Water systemCountyPopulation servedTypeSource
1Cleveland Public Water SystemCuyahoga1,308,955CommunitySurface water
2Columbus Public Water SystemFranklin1,305,946CommunitySurface water
3Cincinnati Public Water SystemHamilton750,200CommunitySurface water
4Toledo City ofLucas360,000CommunitySurface water
5Akron City PwsSummit280,000CommunitySurface water
6Montgomery County Water Services 1 PwsMontgomery150,207CommunityPurchased surface water
7Del-Co Water Company, Inc..Delaware150,000CommunitySurface water
8Dayton Public Water SystemMontgomery141,407CommunitySurface water
9Clermont Public Water SystemClermont133,059CommunitySurface water
10Youngstown City PwsMahoning130,530CommunityPurchased surface water
11Butler Co. Water District 2 PwsButler116,572CommunityPurchased surface water
12Canton Public Water SystemStark107,113CommunityGroundwater
13Aqua Ohio - Massillon PwsStark95,636CommunityGroundwater
14Montgomery County Water Services 2 PwsMontgomery83,033CommunityPurchased surface water
15Warren CountyWarren81,975CommunityGroundwater
16Lake County West Water SubdistrictLake78,379CommunitySurface water
17Aqua Ohio - MentorLake74,500CommunitySurface water
18Rural Lorain Co. Water ALorain73,125CommunityPurchased surface water
19Elyria Water DepartmentLorain68,000CommunitySurface water
20Lima CityAllen65,619CommunitySurface water
21Lorain City PwsLorain64,152CommunitySurface water
22Hamilton Public Water SystemButler62,447CommunityGroundwater
23Springfield City PwsClark60,680CommunityGroundwater
24Aqua Ohio - StruthersMahoning58,551CommunitySurface water
25Findlay City PwsHancock54,040CommunitySurface water

By county

Geauga248 systemsSummit202 systemsStark173 systemsWayne165 systemsPortage154 systemsLogan123 systemsRichland114 systemsColumbiana107 systemsFranklin90 systemsClark89 systemsHolmes85 systemsTrumbull80 systemsLicking80 systemsTuscarawas78 systemsMercer78 systemsMontgomery72 systemsFairfield72 systemsDarke67 systemsMahoning66 systemsSeneca63 systemsMedina59 systemsMiami57 systemsGreene56 systemsMadison55 systemsSandusky53 systemsCarroll53 systemsAshtabula51 systemsWood50 systemsAshland49 systemsHocking45 systemsLucas43 systemsWilliams41 systemsChampaign40 systemsHancock40 systemsKnox40 systemsAllen39 systemsShelby39 systemsOttawa37 systemsPutnam36 systemsUnion36 systemsJefferson35 systemsCoshocton33 systemsPickaway33 systemsVan Wert31 systemsHardin30 systemsAuglaize30 systemsPreble29 systemsMarion29 systemsHarrison28 systemsHamilton26 systemsDefiance25 systemsPaulding25 systemsHuron25 systemsPerry25 systemsFulton23 systemsHenry23 systemsWyandot22 systemsMuskingum21 systemsLake21 systemsWarren21 systemsBelmont20 systemsButler20 systemsWashington18 systemsScioto17 systemsLorain16 systemsMorrow16 systemsPike15 systemsGuernsey14 systemsFayette14 systemsMorgan14 systemsCrawford14 systemsAthens13 systemsErie13 systemsCuyahoga11 systemsHighland9 systemsClermont9 systemsClinton9 systemsRoss8 systemsMeigs8 systemsJackson7 systemsBrown7 systemsAdams6 systemsNoble6 systemsMonroe6 systemsLawrence6 systemsDelaware5 systemsVinton4 systemsHillsdale3 systemsGallia3 systemsBedford3 systemsGratiot3 systemsBranch3 systems
Benzie2 systems
Muskegon2 systems
Lancaster2 systems
Venango2 systems
Shiawassee2 systems
Genesee2 systems
Clare1 systems
Schuylkill1 systems
Pershing1 systems
Otsego1 systems
Emmet1 systems
Frederick1 systems
Randolph1 systems
Lebanon1 systems
Luzerne1 systems
Cass1 systems
Berrien1 systems
Lehigh1 systems
Berks1 systems
Shasta1 systems
St. Clair1 systems
Ogle1 systems
Garrett1 systems
Lenawee1 systems
Isabella1 systems
Custer1 systems
Mecosta1 systems
Newaygo1 systems
Sanilac1 systems
Marquette1 systems
Marshall1 systems
Allegan1 systems
Barry1 systems
Kosciusko1 systems
Manistee1 systems
Guilford1 systems
Harris1 systems
Brazoria1 systems
Accomack1 systems
Orangeburg1 systems
Roscommon1 systems
New Kent1 systems