Ohio Tap Water Quality

Explore tap water quality data for counties across Ohio. View water system reports, track violations, monitor drinking water safety, and check fluoridation status in your community.

Counties

88

With water systems

Population

10,556,123

Served by water systems

Water Systems

1,138

Total water systems

Violators

20

Systems with serious violations

Searching by your address yields the most accurate results. Searching by town or water system may not show all systems due to how the EPA categorizes data. Some towns may be listed under counties, and water system boundaries don't always align with town boundaries.

Filter Results

Ohio Counties

Adams

Population: 31,068

Water Systems: 6

Allen

Population: 84,197

Water Systems: 8

Ashland

Population: 25,743

Water Systems: 10

Serious Violator

Ashtabula

Population: 79,351

Water Systems: 12

Serious Violator

Athens

Population: 75,476

Water Systems: 13

Auglaize

Population: 30,093

Water Systems: 8

Belmont

Population: 62,529

Water Systems: 14

Serious Violator

Brown

Population: 47,745

Water Systems: 9

Butler

Population: 375,185

Water Systems: 13

Carroll

Population: 6,981

Water Systems: 6

Champaign

Population: 18,684

Water Systems: 11

Clark

Population: 93,946

Water Systems: 27

Clermont

Population: 189,721

Water Systems: 10

Clinton

Population: 20,927

Water Systems: 5

Columbiana

Population: 59,306

Water Systems: 17

Coshocton

Population: 14,604

Water Systems: 7

Crawford

Population: 27,788

Water Systems: 4

Cuyahoga

Population: 1,399,079

Water Systems: 7

Darke

Population: 25,006

Water Systems: 11

Defiance

Population: 24,753

Water Systems: 9

Delaware

Population: 195,181

Water Systems: 3

Erie

Population: 81,167

Water Systems: 12

Serious Violator

Fairfield

Population: 93,723

Water Systems: 21

Fayette

Population: 23,765

Water Systems: 7

Franklin

Population: 1,477,038

Water Systems: 30

Fulton

Population: 25,128

Water Systems: 9

Gallia

Population: 28,959

Water Systems: 3

Serious Violator

Geauga

Population: 22,409

Water Systems: 31

Greene

Population: 167,849

Water Systems: 19

Guernsey

Population: 28,937

Water Systems: 6

Hamilton

Population: 829,012

Water Systems: 12

Hancock

Population: 59,349

Water Systems: 8

Hardin

Population: 18,536

Water Systems: 8

Serious Violator

Harrison

Population: 10,785

Water Systems: 15

Henry

Population: 14,885

Water Systems: 10

Highland

Population: 42,501

Water Systems: 5

Hocking

Population: 9,077

Water Systems: 7

Holmes

Population: 10,828

Water Systems: 11

Huron

Population: 65,234

Water Systems: 14

Jackson

Population: 36,466

Water Systems: 6

Jefferson

Population: 56,831

Water Systems: 18

Knox

Population: 31,478

Water Systems: 10

Lake

Population: 228,741

Water Systems: 6

Serious Violator

Lawrence

Population: 61,075

Water Systems: 6

Serious Violator

Licking

Population: 110,731

Water Systems: 22

Logan

Population: 22,447

Water Systems: 16

Serious Violator

Lorain

Population: 329,650

Water Systems: 16

Lucas

Population: 547,329

Water Systems: 8

Serious Violator

Madison

Population: 31,715

Water Systems: 17

Serious Violator

Mahoning

Population: 207,862

Water Systems: 12

Marion

Population: 47,505

Water Systems: 4

Medina

Population: 108,067

Water Systems: 14

Serious Violator

Meigs

Population: 28,497

Water Systems: 6

Mercer

Population: 22,904

Water Systems: 9

Miami

Population: 88,642

Water Systems: 16

Monroe

Population: 13,313

Water Systems: 6

Montgomery

Population: 512,625

Water Systems: 23

Morgan

Population: 5,135

Water Systems: 8

Morrow

Population: 7,140

Water Systems: 5

Serious Violator

Muskingum

Population: 69,664

Water Systems: 11

Noble

Population: 11,421

Water Systems: 6

Ottawa

Population: 38,472

Water Systems: 10

Paulding

Population: 7,762

Water Systems: 6

Serious Violator

Perry

Population: 26,710

Water Systems: 21

Serious Violator

Pickaway

Population: 41,285

Water Systems: 20

Pike

Population: 24,779

Water Systems: 8

Portage

Population: 101,221

Water Systems: 34

Preble

Population: 21,241

Water Systems: 12

Putnam

Population: 15,535

Water Systems: 10

Richland

Population: 89,754

Water Systems: 48

Serious Violator

Ross

Population: 69,602

Water Systems: 7

Serious Violator

Sandusky

Population: 30,061

Water Systems: 7

Scioto

Population: 86,751

Water Systems: 17

Serious Violator

Seneca

Population: 38,796

Water Systems: 11

Serious Violator

Shelby

Population: 29,127

Water Systems: 16

Serious Violator

Stark

Population: 289,089

Water Systems: 38

Serious Violator

Summit

Population: 438,951

Water Systems: 33

Serious Violator

Trumbull

Population: 151,114

Water Systems: 29

Tuscarawas

Population: 62,233

Water Systems: 14

Union

Population: 28,779

Water Systems: 4

Van Wert

Population: 13,632

Water Systems: 5

Vinton

Population: 3,730

Water Systems: 3

Warren

Population: 210,509

Water Systems: 17

Serious Violator

Washington

Population: 60,927

Water Systems: 15

Wayne

Population: 58,748

Water Systems: 32

Williams

Population: 21,708

Water Systems: 13

Wood

Population: 107,776

Water Systems: 21

Wyandot

Population: 12,048

Water Systems: 4