Washington Tap Water Quality

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

Counties

39

With water systems

Population

8,978,497

Served by water systems

Water Systems

2,310

Total water systems

Violators

14

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.

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Washington Counties

Adams

Population: 16,950

Water Systems: 30

Asotin

Population: 25,114

Water Systems: 2

Serious Violator

Benton

Population: 250,304

Water Systems: 44

Serious Violator

Chelan

Population: 91,607

Water Systems: 47

Clallam

Population: 85,019

Water Systems: 62

Clark

Population: 597,102

Water Systems: 25

Columbia

Population: 3,430

Water Systems: 2

Cowlitz

Population: 105,878

Water Systems: 31

Douglas

Population: 36,151

Water Systems: 19

Serious Violator

Ferry

Population: 3,644

Water Systems: 11

Franklin

Population: 120,150

Water Systems: 30

Garfield

Population: 1,477

Water Systems: 3

Serious Violator

Grant

Population: 89,461

Water Systems: 80

Grays Harbor

Population: 76,749

Water Systems: 35

Serious Violator

Island

Population: 91,359

Water Systems: 234

Jefferson

Population: 40,024

Water Systems: 24

Serious Violator

King

Population: 3,049,247

Water Systems: 154

Kitsap

Population: 318,083

Water Systems: 151

Serious Violator

Kittitas

Population: 35,715

Water Systems: 36

Serious Violator

Klickitat

Population: 16,781

Water Systems: 23

Serious Violator

Lewis

Population: 65,652

Water Systems: 51

Serious Violator

Lincoln

Population: 8,852

Water Systems: 16

Mason

Population: 57,932

Water Systems: 121

Okanogan

Population: 28,176

Water Systems: 42

Pacific

Population: 31,207

Water Systems: 17

Serious Violator

Pend Oreille

Population: 9,194

Water Systems: 15

Pierce

Population: 1,080,799

Water Systems: 230

San Juan

Population: 14,682

Water Systems: 42

Skagit

Population: 155,057

Water Systems: 40

Skamania

Population: 9,004

Water Systems: 13

Snohomish

Population: 861,515

Water Systems: 119

Serious Violator

Spokane

Population: 602,955

Water Systems: 87

Serious Violator

Stevens

Population: 28,809

Water Systems: 33

Thurston

Population: 348,158

Water Systems: 196

Wahkiakum

Population: 3,606

Water Systems: 4

Walla Walla

Population: 66,014

Water Systems: 33

Whatcom

Population: 238,570

Water Systems: 101

Whitman

Population: 67,390

Water Systems: 19

Yakima

Population: 246,680

Water Systems: 88