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PFAS in Washington drinking water

EPA's final UCMR 5 data covers 248 public water systems in Washington, serving about 8.9 million people. PFAS turned up in 68 of them (27%). 24 averaged above at least one EPA limit at a sampling point, affecting about 1.3 million people.

Highest PFOA and PFOS averages among systems serving 1,000 or more: Artondale Water System (6.3 / 154 ppt), City of Vancouver (10.9 / 18.4 ppt), City of Richland (10.1 / 17.0 ppt), Parkland Light & Water Company (6.2 / 13.8 ppt) and Southwood Water System (6.2 / 8.9 ppt).

Every tested system in Washington

Largest first. PFOA and PFOS columns show the average at each system's worst sampling point; EPA's limit for each is 4 ppt. Filter by name:

Water system People PFOA PFOS PFAS found Result
Seattle Public Utilities · Seattle 1,161,961 - - 0 None found
City of Tacoma Water Division · Tacoma 446,170 - - 2 Below limits
City of Vancouver · Vancouver 373,047 10.9 18.4 7 Above limit
City of Spokane · Spokane 346,138 - 3.1 4 Sample at limit
City of Bellevue · Bellevue 321,349 - - 0 None found
Alderwood Water District · Lynnwood 245,715 - - 0 None found
City of Everett Public Works Dept. · Everett 215,774 - - 0 None found
Kent Water Department · Kent 166,421 - - 1 Below limits
City of Redmond Water System · Redmond 163,335 - 2.5 2 Sample at limit
Clark Public Utilities · Vancouver 153,526 4.0 4.2 5 Above limit
Lakehaven Water and Sewer District · Federal Way 148,809 - 2.1 6 Sample at limit
City of Bellingham-water Division · Bellingham 141,127 - - 0 None found
City of Olympia · Olympia 126,966 2.1 2.9 5 Sample at limit
City of Kennewick · Kennewick 118,164 2.2 10.0 6 Above limit
Pasco Water Department · Pasco 115,102 - - 0 None found
City of Yakima Water Division · Yakima 112,858 - - 0 None found
Skagit County PUD 1 Judy Res · Mount Vernon 111,415 - - 1 Below limits
City of Renton · Renton 108,091 - - 1 Below limits
City of Auburn · Auburn 107,655 - - 1 Below limits
City of Richland · Richland 106,499 10.1 17.0 8 Above limit
Lacey Water Department · Lacey 105,178 - - 4 Below limits
Highline Water District · Kent 100,170 - - 0 None found
Northshore Utility District · Kenmore 99,789 - - 0 None found
City of Puyallup · Puyallup 94,520 - - 1 Below limits
Marysville Utilities · Marysville 88,582 - - 0 None found
Lakewood Water District · Lakewood 82,425 - 5.6 5 Above limit
Sammamish Plateau Water & Sewer · Sammamish 79,362 - 9.7 6 Above limit
Soos Creek Water & Sewer District · Renton 74,172 - - 0 None found
City of Bremerton · Bremerton 72,951 - - 1 Below limits
City of Kirkland · Kirkland 69,243 - - 0 None found
City of Lynnwood · Lynnwood 68,204 - - 0 None found
Sno PUD 1 - Lake Stevens · Everett 67,710 - - 0 None found
Woodinville Water District · Woodinville 66,699 - - 0 None found
Silver Lake Water & Sewer District · Bothell 65,033 - - 0 None found
Southwood Water System · Tacoma 64,155 6.2 8.9 6 Above limit
Longview Water Department · Longview 57,617 - - 0 None found
Covington Water District · Kent 56,172 - 8.4 5 Above limit
City of Tumwater · Tumwater 51,802 - - 1 Below limits
Port of Seattle/seatac Airport · Seattle 49,483 - - 0 None found
King County Water District #20 · Seattle 48,469 - - 0 None found
City of Wenatchee · Wenatchee 43,690 - - 0 None found
Issaquah Water System · Issaquah 43,584 - - 0 None found
Bonney Lake Water Department City · Buckley 43,371 - - 1 Below limits
Walla Walla Water Division · Walla Walla 42,959 - - 0 None found
Nob Hill Water Association · Yakima 38,050 - - 0 None found
Tukwila Water Department · Tukwila 36,298 - - 0 None found
Firgrove Mutual INC · Puyallup 36,168 4.4 8.6 3 Above limit
JBLM Lewis · Joint Base Lewis-mcchord 35,414 4.9 10.2 5 Above limit
Silverdale Water Dist 16 · Silverdale 35,163 - - 0 None found
Spanaway Water Company · Spanaway 34,506 3.1 7.2 6 Above limit
City of Edmonds · Edmonds 34,065 - - 0 None found
Parkland Light & Water Company · Tacoma 33,775 6.2 13.8 6 Above limit
City of Bothell Water · Bothell 33,643 - - 0 None found
North City Water District · Shoreline 32,847 - - 0 None found
City of Moses Lake · Moses Lake 32,428 - 1.8 5 Sample at limit
Camas Municipal Water Sewer System · Camas 31,794 2.2 6.2 3 Above limit
Mukilteo Water & Wastewater Distr · Mukilteo 31,437 - - 0 None found
City of Pullman Water Department · Pullman 31,315 - - 0 None found
City of Mercer Island · Mercer Island 31,057 - - 0 None found
City of Battle Ground Water Dept · Battle Ground 30,237 - - 0 None found
Arlington Water Dept · Arlington 29,508 - - 1 Below limits
Fife Dept of Public Works · Fife 29,091 - - 2 Below limits
West Sound Utility District #1 · Port Orchard 28,930 2.9 - 4 Sample at limit
Cedar River Water & Sewer District · Maple Valley 28,671 - - 1 Below limits
Centralia Public Works - Water · Centralia 28,164 - 5.5 2 Above limit
City of Port Angeles · Port Angeles 28,067 - - 0 None found
Whitworth Water District 2 · Mead 26,883 - 2.3 4 Sample at limit
East Wenatchee Water District · East Wenatchee 26,519 - - 0 None found
City of Mountlake Terrace · Mountlake Terrace 26,402 - - 0 None found
City of Anacortes · Mount Vernon 25,109 - - 0 None found
Cross Valley Water District · Snohomish 24,695 - - 3 Below limits
Vera Water & Power · Spokane Valley 24,692 - - 0 None found
North Perry Ave Water District · Bremerton 24,402 - - 0 None found
Lake Meridian Water District · Kent 24,231 - - 0 None found
City of Oak Harbor · Oak Harbor 23,675 - - 0 None found
King County Water District #49 · Burien 23,492 - - 0 None found
Monroe Water System · Monroe 23,467 - - 0 None found
Enumclaw Water Department · Enumclaw 23,276 - - 0 None found
City of Aberdeen · Aberdeen 22,867 - - 0 None found
PUD #1 of Asotin County · Clarkston 21,930 - - 0 None found
King County Water District #125 · Seattle 21,904 - - 0 None found
Washington State University · Pullman 21,506 - - 0 None found
City of Washougal · Washougal 21,441 - 7.6 3 Above limit
City of West Richland · West Richland 21,231 - - 0 None found
Ridgefield Public Works · Ridgefield 21,225 - - 0 None found
Consolidated Irrig Dist 19 System 2 · Greenacres 21,220 - - 0 None found
Ellensburg Water Dept · Ellensburg 20,900 - - 0 None found
Snoqualmie Water · Snoqualime 20,222 - - 0 None found
King County Water District No 90 · Renton 20,100 - - 0 None found
Lynden Water Department · Lynden 20,062 - - 0 None found
Ferndale · Ferndale 19,305 - - 0 None found
Summit Water & Supply CO · Tacoma 19,125 - - 1 Below limits
Spo CO Water Dist 3 Sys 2 · Spokane 19,035 - - 0 None found
Modern Electric Water CO · Spokane 18,487 - - 0 None found
City of Poulsbo · Poulsbo 18,400 - - 0 None found
Olympic View Water & Sewer District · Edmonds 17,784 - - 0 None found
City of Stanwood Water Dept · Stanwood 17,586 - - 0 None found
City of Yelm · Yelm 17,355 - - 0 None found
City of Sunnyside · Sunnyside 17,194 - - 0 None found
Eastern Washington University · Cheney 17,108 - - 0 None found
City of Port Townsend · Port Townsend 17,053 - - 0 None found
City of Cheney · Cheney 16,954 - - 0 None found
Naval Base Kitsap at Bangor · Silverdale 16,828 - - 0 None found
Naval Air Station/whidbey Island · Nas Whidbey Island 16,595 - - 0 None found
Gig Harbor Water Dept · Gig Harbor 16,510 - - 0 None found
North Peninsula · Poulsbo 16,449 - - 0 None found
City of Sumner · Sumner 16,438 - - 0 None found
City of Snohomish · Snohomish 16,367 - - 0 None found
Chelan CO PUD 1 · Wenatchee 16,190 - - 0 None found
Coal Creek Utility District · Newcastle 15,989 - - 0 None found
City of Kelso · Kelso 15,775 - - 0 None found
Port Orchard Water · Port Orchard 15,355 - - 0 None found
Fruitland Mutual Water Company · Puyallup 15,313 1.0 - 4 Sample at limit
City of Shelton · Shelton 15,089 - - 0 None found
Quimper · Port Townsend 14,548 - - 1 Below limits
Liberty Lake Sewer & Water District · Liberty Lake 14,500 - - 1 Below limits
City of Sequim · Sequim 14,293 - - 1 Below limits
City of Bainbridge Island · Bainbridge Island 13,491 - - 0 None found
City of Dupont Water System · Dupont 13,141 - - 0 None found
City of Prosser · Prosser 12,070 - - 0 None found
Skyway Water & Sewer · Seattle 12,036 - - 0 None found
Beacon Hill Water & Sewer District · Kelso 11,969 - - 0 None found
Naval Base Kitsap at Bremerton · Silverdale 11,792 - - 0 None found
Chehalis Water Department · Chehalis 11,718 - - 0 None found
Hoquiam Water Department · Hoquiam 11,456 - - 0 None found
City of Duvall · Duvall 11,050 - - 0 None found
City of Grandview · Grandview 11,010 - - 0 None found
City of Woodland · Woodland 10,640 - - 1 Below limits
Manchester Water District · Manchester 10,475 - - 0 None found
City of Orting · Orting 10,332 - - 0 None found
Lwwsd - South Shore Water System · Bellingham 10,028 - - 0 None found
Ne Sammamish Sewer & Water District · Sammamish 9,702 - - 0 None found
Mountain View-edgewood Water CO · Edgewood 9,680 - - 1 Below limits
Fairchild Air Force Base · Fairchild Afb 9,544 - 3.1 5 Above limit
City of Airway Heights · Airway 9,489 - - 4 Below limits
Consolidated Irrig Dist 19 System 1 · Greenacres 9,434 - - 0 None found
City of Chelan Water Dept · Chelan 9,425 - - 0 None found
Ocean Shores Water Dept · Hoquiam 9,347 - - 0 None found
City of Selah · Selah 9,331 - - 0 None found
Birch Bay Water & Sewer District · Birch Bay 9,046 - - 0 None found
Toppenish Water Department · Toppenish 8,950 - - 0 None found
Port Angeles Composite · Carlsborg 8,872 - - 1 Below limits
Othello Water Department · Othello 8,755 - - 0 None found
Union Hill Water Association INC · Redmond 8,720 - - 0 None found
Ephrata Water Department · Ephrata 8,718 - - 0 None found
City of North Bend · North Bend 8,710 - - 0 None found
Town of Steilacoom · Steilacoom 8,545 - - 0 None found
Sultan Water Department · Sultan 8,424 - - 0 None found
City of Quincy Water Department · Quincy 8,415 - - 0 None found
Yak CO - Terrace Heights · Yakima 8,410 - - 0 None found
College Place Water Dept · College Place 8,147 - - 0 None found
North Beach Water · Ocean Park 8,093 - - 0 None found
City of Milton · Milton 8,078 - - 4 Below limits
City of Kalama · Kalama 8,020 - - 0 None found
City of Fircrest · Fircrest 7,927 - - 1 Below limits
City of Pacific · Othello 7,925 - - 1 Below limits
Model Irrigation Dist #18 · Spokane 7,903 2.1 5.2 5 Above limit
Tanglewilde-Thompson Place 600 · Lacey 7,900 - - 0 None found
Buckley Water · Buckley 7,842 - - 0 None found
Stevens CO PUD - Suncrest · Loon Lake 7,484 - - 2 Below limits
Peacock Hill · Tacoma 7,401 - - 7 Above limit
JBLM McChord Field · Joint Base Lewis-mcchord 7,290 - 5.2 2 Above limit
Lake Chelan Reclamation District · Manson 6,798 - - 0 None found
City of Elma · Elma 6,638 - - 0 None found
Sallal Water Association INC · North Bend 6,600 - - 0 None found
Union Gap Water · Union Gap 6,433 - - 0 None found
Energy Dept Of/200w · Richland 6,351 - - 0 None found
City of Blaine · Blaine 6,319 - - 0 None found
Pasadena Park Irr Dist 17 · Spokane 6,269 - - 0 None found
Spo CO Water Dist 3 Sys 4 · Spokane 6,233 - - 0 None found
City of Montesano · Montesano 6,204 - - 0 None found
Snoqualmie Pass Utility District · Snoqualmie Pass 5,832 - - 0 None found
Artondale Water System · Tacoma 5,828 6.3 154 8 Above limit
Seven Lakes Water Association · Stanwood 5,823 - - 0 None found
Benton City Water · Benton City 5,626 - 4.3 6 Above limit
Moxee Water Department · Moxee 5,599 - - 0 None found
North Bainbridge Water CO · Poulsbo 5,490 - - 0 None found
City of Deer Park · Deer Park 5,435 - 3.8 3 Sample at limit
King County Water District #54 · Kent 5,373 - - 0 None found
City of Mattawa · Mattawa 5,370 - - 0 None found
City of Granite Falls · Granite Falls 5,349 - - 0 None found
Westport Water Department · Westport 5,346 - - 0 None found
Water District 19 · Vashon 5,335 - - 0 None found
Wapato Waterworks · Wapato 5,255 - - 0 None found
Point Evans · Tacoma 5,211 - - 0 None found
City of Connell · Connell 5,150 - - 0 None found
Grays Harbor CO Water Dist 2 · Montesano 5,112 - - 0 None found
Minterbrook · Tacoma 5,083 - - 3 Below limits
Spokane Business & Industrial Park · Spokane 5,000 - - 0 None found
City of Medical Lake · Medical Lake 4,982 - 2.2 2 Sample at limit
Colville Water Department · Colville 4,945 - - 0 None found
City of Omak · Omak 4,940 - - 1 Below limits
Longmire · Ashford 4,871 - - 0 None found
Vinland · Poulsbo 4,801 - - 0 None found
City of Warden · Warden 4,674 - - 0 None found
Pattison · Lacey 4,643 - - 0 None found
Long Beach Water Department · Long Beach 4,628 - - 0 None found
Raymond Water Department · Raymond 4,620 - - 0 None found
Castle Rock Municipal Water · Castle Rock 4,367 - - 0 None found
Orchard Avenue Irrigation Dist 6 · Spokane 4,330 - - 0 None found
City of Goldendale · Goldendale 4,314 - - 0 None found
East Spokane Water Dist 1 · Spokane Valley 4,285 - 2.8 1 Sample at limit
Trentwood Irrigation District 3 · Spokane 4,228 2.6 10.2 5 Above limit
Suquamish · Poulsbo 4,203 - - 0 None found
Crystal Mountain INC · Raymond 4,154 - - 0 None found
Irvin Water District #6 · Spokane 4,150 - - 1 Below limits
Town of Coupeville · Coupeville 4,142 4.9 - 7 Above limit
City of White Salmon · White Salmon 4,077 - - 0 None found
Stevens Pass Water System · Leavenworth 4,053 - - 0 None found
Granger Water Department · Granger 3,993 - - 0 None found
Eatonville Water Dept · Eatonville 3,945 - - 0 None found
City of Everson · Everson 3,893 - - 0 None found
King County Water District 119 · Duvall 3,800 - - 0 None found
Spo CO Water Dist 3 Sys 3 · Spokane 3,768 - - 0 None found
Parkview Terrace · Tacoma 3,730 - - 1 Below limits
Eastsound Water Users Association · Eastsound 3,711 - - 0 None found
Lake Cushman System 5 · Hoodsport 3,675 - - 2 Below limits
Town of Friday Harbor · Friday Harbor 3,543 - - 0 None found
Town of Naches · Naches 3,512 - - 0 None found
City of Colfax Water Department · Colfax 3,507 - - 0 None found
Forks Municipal Water Dept · Forks 3,468 - - 0 None found
Horizons West · Tacoma 3,454 - - 1 Below limits
City of Tenino · Tenino 3,336 - - 0 None found
Lake Forest Park Water District · Lake Forest Park 3,171 - - 0 None found
Snake River Housing Water System · Yakima 3,036 - - 0 None found
Mccormick Woods · Port Orchard 2,760 - - 0 None found
West Sequim Bay INC · Sequim 2,759 - - 0 None found
City of Gold Bar · Goldbar 2,745 - - 0 None found
Columbia Valley Water District · Maple Falls 2,648 - - 0 None found
Crescent Water Assn · Joyce 2,360 - - 0 None found
Shelter Bay Community INC · La Conner 2,212 - - 0 None found
Heights Water · Vashon 2,051 - - 0 None found
Northwest Trek · Eatonville 1,283 - - 0 None found
Quistorff · Tacoma 1,113 - 11.5 7 Above limit
Whatcom County Water Dist 13 · Maple Falls 795 - - 0 None found
Lost Lake Property Owners Assn · Coupeville 736 - - 0 None found
City of Harrington · Waverly 650 - - 0 None found
Seabeck · Poulsbo 610 - - 0 None found
Rogers Group Properties I LLC · North Bend 570 - - 0 None found
Consolidated Support Services · Medical Lake 569 - - 0 None found
Stevens CO PUD - Valley · Loon Lake 550 - - 0 None found
Dungeness Meadows · Sequim 488 - - 0 None found
Northwest Water Assoc. Inc. · Lynden 400 2.4 - 2 Sample at limit
Emerald Lake · Shelton 331 - - 0 None found
Bayshore · Union 130 - - 0 None found
Hi Valley View · Yakima 67 - - 0 None found
Cedar Grove Mobile Park · Sequim 40 - - 0 None found
Seascape Water Association · Stanwood 28 - - 0 None found

On a private well in Washington?

EPA's program only covers public systems. Private wells are never part of UCMR 5, so the only way to know is to test. Our well testing guide covers which lab tests to order, and the best well water systems covers what to install once you have results.

Cite this page

Well & Tap. "PFAS in Washington drinking water: results for 248 systems." Data: U.S. EPA UCMR 5, final release August 2026. https://wellandtap.com/pfas/washington/

Source: EPA UCMR 5 final occurrence data (August 2026); population from EPA SDWIS. Method.