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AquaCensus

Washington public water systems

4,705 active systems regulated under the Safe Drinking Water Act, serving a reported 10.1M people across 74 counties.

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

Active systems

4,705

Population served

10.1M

Community systems

2,392

Groundwater share

94.2%

System types in Washington

2,392

Community water system

401

Non-transient non-community water system

1,912

Transient non-community water system

Largest water systems in Washington

The largest active public water systems in Washington by population served
#Water systemCountyPopulation servedTypeSource
1Seattle Public UtilitiesKing1,161,961CommunitySurface water
2Tacoma Water Division City ofPierce446,170CommunitySurface water
3Vancouver City ofClark373,047CommunityGroundwater
4Spokane City ofSpokane343,167CommunityGroundwater
5Bellevue City ofKing321,349CommunityPurchased surface water
6Alderwood Water DistrictSnohomish245,715CommunityPurchased surface water
7Everett Public Works Dept. City ofSnohomish215,774CommunitySurface water
8Kent Water DepartmentKing166,421CommunityPurchased surface water
9Redmond Water System City ofKing163,335CommunityPurchased surface water
10Clark Public UtilitiesClark153,526CommunityGroundwater
11Lakehaven Water and Sewer DistrictKing148,809CommunityPurchased surface water
12Bellingham-Water Division City ofWhatcom141,127CommunitySurface water
13Olympia City ofThurston126,966CommunityGroundwater
14Kennewick City ofBenton118,164CommunitySurface water
15Pasco Water DepartmentFranklin115,102CommunitySurface water
16Yakima Water Division City ofYakima112,858CommunitySurface water
17Skagit County PUD 1 Judy ResSkagit111,415CommunitySurface water
18Renton City ofKing108,091CommunityGroundwater
19Auburn City ofKing107,655CommunityGroundwater
20Richland City ofBenton106,499CommunitySurface water
21Lacey Water DepartmentThurston105,178CommunityGroundwater
22Highline Water DistrictKing100,170CommunityPurchased surface water
23Northshore Utility DistrictKing99,789CommunityPurchased surface water
24Marysville UtilitiesSnohomish88,582CommunityPurchased surface water
25Sammamish Plateau Water & SewerKing79,362CommunityPurchased surface water

By county

Pierce359 systemsThurston322 systemsIsland307 systemsGrant265 systemsMason240 systemsKitsap220 systemsYakima217 systemsKing214 systemsWhatcom183 systemsSnohomish168 systemsLewis166 systemsSpokane163 systemsChelan130 systemsOkanogan119 systemsSan Juan112 systemsBenton108 systemsClallam100 systemsKittitas96 systemsGrays Harbor88 systemsSkagit86 systemsFranklin80 systemsCowlitz77 systemsClark72 systemsJefferson70 systemsWalla Walla69 systemsStevens65 systemsSkamania56 systemsKlickitat51 systemsAdams49 systemsDouglas46 systemsPend Oreille44 systemsPacific38 systemsWhitman33 systemsLincoln33 systemsFerry32 systemsColumbia13 systemsKootenai9 systemsGarfield9 systemsUmatilla7 systemsAsotin7 systemsLatah6 systemsWahkiakum6 systemsBonner6 systemsLinn3 systems
Cassia2 systems
Marion2 systems
Matagorda2 systems
Deschutes2 systems
Union2 systems
Malheur2 systems
Medina1 systems
Rio Grande1 systems
Lexington1 systems
Licking1 systems
Lane1 systems
Jackson1 systems
Northumberland1 systems
Huntingdon1 systems
Boundary1 systems
Lackawanna1 systems
Fresno1 systems
Idaho1 systems
Clackamas1 systems
Del Norte1 systems
Luzerne1 systems
Josephine1 systems
Tehama1 systems
Travis1 systems
Trinity1 systems
Otsego1 systems
Waller1 systems
Montezuma1 systems
Richland1 systems
Coos1 systems