Systems with a yearly average above an EPA comparison level
8.2%20 of 243 active community water systems
All 243 systems met the sampling requirement for a yearly average. Of those systems, 20 had at least one yearly average above an EPA comparison level and 223 did not.
EPA-based study benchmark: a fixed, unrounded research cutoff used to reproduce EPA’s final UCMR 5 technical-assistance classification based on the April 2024 federal levels. It is not a current federal or state standard. The label does not determine compliance, household exposure, or health risk.
State rules: The labels on this page use fixed research cutoffs based on the April 2024 federal levels. Washington may use different current standards or guidance. These UCMR 5 results do not determine current federal or state compliance. Find the official Washington drinking-water program →
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Find your water system
A ZIP code finds possible public water systems for an area; it cannot identify the supplier for a specific home. Confirm the provider using a water bill or utility record.
Compound summary
System counts in Washington
Each count shows how many included water systems had a yearly average above the named EPA comparison level.
| EPA rounding cutoff | Systems above comparison level | Water systems included | Percent |
|---|---|---|---|
| PFOA: 4 ppt level; unrounded average ≥4.05 ppt after applying EPA rounding | 4 | 243 | 1.6% |
| PFOS: 4 ppt level; unrounded average ≥4.05 ppt after applying EPA rounding | 19 | 243 | 7.8% |
| PFHxS: 10 ppt level; unrounded average ≥15 ppt after applying EPA rounding | 3 | 243 | 1.2% |
| PFNA: 10 ppt level; unrounded average ≥15 ppt after applying EPA rounding | 0 | 243 | 0.0% |
| HFPO-DA: 10 ppt level; unrounded average ≥15 ppt after applying EPA rounding | 0 | 243 | 0.0% |
| Hazard Index: 1 level; unrounded index ≥1.5 and at least two detected components | 3 | 243 | 1.2% |
System directory
Community water systems with complete monitoring
“Complete monitoring” means at least one sampling location had every required sample needed to calculate a yearly average. It does not mean every location or home was tested. Each PWSID appears once, preventing double counting across ZIP associations.
| Public water system | PWSID | Population served | Primary source | Sampling locations | EPA comparison result |
|---|---|---|---|---|---|
| ABERDEEN CITY OF | WA5300050 | 22,867 | Surface water | 1 | No available average above comparison levels |
| AIRWAY HEIGHTS CITY OF | WA5300650 | 9,489 | Ground water | 2 | No available average above comparison levels |
| ALDERWOOD WATER DISTRICT | WA5301300 | 245,715 | Surface water purchased | 1 | No available average above comparison levels |
| ANACORTES CITY OF | WA5302200 | 25,109 | Surface water | 1 | No available average above comparison levels |
| ARLINGTON WATER DEPT | WA5302950 | 29,508 | Surface water purchased | 3 | No available average above comparison levels |
| ARTONDALE WATER SYSTEM | WA5303160 | 5,828 | Ground water | 10 | No available average above comparison levels |
| Auburn City of | WA5303350 | 107,655 | Ground water | 6 | No available average above comparison levels |
| BAINBRIDGE ISLAND CITY OF | WA5397650 | 13,491 | Ground water | 4 | No available average above comparison levels |
| BAYSHORE | WA5304900 | 130 | Ground water | 1 | No available average above comparison levels |
| BEACON HILL WATER & SEWER DISTRICT | WA5315650 | 11,969 | Ground water purchased | 1 | No available average above comparison levels |
| BELLEVUE CITY OF | WA5305575 | 321,349 | Surface water purchased | 2 | No available average above comparison levels |
| BELLINGHAM-WATER DIVISION CITY OF | WA5305600 | 141,127 | Surface water | 1 | No available average above comparison levels |
| BENTON CITY WATER | WA5305800 | 5,626 | Ground water | 3 | Above an EPA comparison level |
| BIRCH BAY WATER & SEWER DISTRICT | WA5395904 | 9,046 | Ground water purchased | 3 | No available average above comparison levels |
| BLAINE CITY OF | WA5307300 | 6,319 | Ground water | 3 | No available average above comparison levels |
| BONNEY LAKE WATER DEPARTMENT CITY | WA5307650 | 43,371 | Surface water purchased | 5 | No available average above comparison levels |
| BOTHELL WATER CITY OF | WA5307900 | 33,643 | Surface water purchased | 1 | No available average above comparison levels |
| BREMERTON CITY OF | WA5308200 | 72,951 | Surface water | 7 | No available average above comparison levels |
| BUCKLEY WATER | WA5309000 | 7,842 | Surface water purchased | 7 | No available average above comparison levels |
| CAMAS MUNICIPAL WATER SEWER SYSTEM | WA5310800 | 31,794 | Ground water | 5 | Above an EPA comparison level |
| CASTLE ROCK MUNICIPAL WATER | WA5311800 | 4,367 | Surface water | 5 | No available average above comparison levels |
| CEDAR GROVE MOBILE PARK | WA5336836 | 40 | Ground water | 1 | No available average above comparison levels |
| CEDAR RIVER WATER & SEWER DISTRICT | WA5341800 | 28,671 | Surface water purchased | 2 | No available average above comparison levels |
| CENTRALIA PUBLIC WORKS - WATER | WA5312200 | 28,164 | Ground water | 3 | Above an EPA comparison level |
| CHEHALIS WATER DEPARTMENT | WA5312250 | 11,718 | Surface water | 1 | No available average above comparison levels |
| CHELAN CO PUD 1 | WA5312284 | 16,190 | Ground water purchased | 1 | No available average above comparison levels |
| CHELAN WATER DEPT CITY OF | WA5312300 | 9,425 | Surface water | 1 | No available average above comparison levels |
| CHENEY CITY OF | WA5312400 | 16,954 | Ground water | 5 | No available average above comparison levels |
| CLARK PUBLIC UTILITIES | WA5313333 | 153,526 | Ground water | 10 | Above an EPA comparison level |
| COAL CREEK UTILITY DISTRICT | WA5341750 | 15,989 | Surface water purchased | 1 | No available average above comparison levels |
| COLFAX WATER DEPARTMENT CITY OF | WA5314000 | 3,507 | Ground water | 3 | No available average above comparison levels |
| COLLEGE PLACE WATER DEPT | WA5314050 | 8,147 | Ground water | 5 | No available average above comparison levels |
| COLVILLE WATER DEPARTMENT | WA5314200 | 4,945 | Ground water | 2 | No available average above comparison levels |
| CONNELL CITY OF | WA5314600 | 5,150 | Ground water | 3 | No available average above comparison levels |
| CONSOLIDATED IRRIG DIST 19 SYSTEM 1 | WA5310220 | 9,434 | Ground water | 3 | No available average above comparison levels |
| CONSOLIDATED IRRIG DIST 19 SYSTEM 2 | WA5310221 | 21,220 | Ground water | 4 | No available average above comparison levels |
| CONSOLIDATED SUPPORT SERVICES | WA5321850 | 569 | Ground water | 1 | No available average above comparison levels |
| COUPEVILLE TOWN OF | WA5315550 | 4,142 | Ground water | 1 | Above an EPA comparison level |
| COVINGTON WATER DISTRICT | WA5341650 | 56,172 | Surface water purchased | 3 | Above an EPA comparison level |
| CRESCENT WATER ASSN | WA5316020 | 2,360 | Surface water | 1 | No available average above comparison levels |
| CROSS VALLEY WATER DISTRICT | WA5316270 | 24,695 | Surface water purchased | 6 | No available average above comparison levels |
| CRYSTAL MOUNTAIN INC | WA5316400 | 4,154 | Surface water | 1 | No available average above comparison levels |
| Columbia Valley Water District | WA5366110 | 2,648 | Ground water | 3 | No available average above comparison levels |
| DEER PARK CITY OF | WA5318500 | 5,435 | Ground water | 8 | No available average above comparison levels |
| DUNGENESS MEADOWS | WA5320445 | 488 | Ground water | 3 | No available average above comparison levels |
| DUPONT WATER SYSTEM CITY OF | WA5320500 | 13,141 | Ground water | 2 | No available average above comparison levels |
| DUVALL CITY OF | WA5320750 | 11,050 | Surface water purchased | 1 | No available average above comparison levels |
| EAST SPOKANE WATER DIST 1 | WA5321650 | 4,285 | Ground water | 4 | No available average above comparison levels |
| EAST WENATCHEE WATER DISTRICT | WA5321800 | 26,519 | Ground water purchased | 1 | No available average above comparison levels |
| EASTERN WASHINGTON UNIVERSITY | WA5321900 | 17,108 | Ground water | 1 | No available average above comparison levels |
| EASTSOUND WATER USERS ASSOCIATION | WA5322170 | 3,711 | Surface water | 4 | No available average above comparison levels |
| EATONVILLE WATER DEPT | WA5322300 | 3,945 | Surface water | 1 | No available average above comparison levels |
| EDMONDS CITY OF | WA5322500 | 34,065 | Surface water purchased | 1 | No available average above comparison levels |
| ELLENSBURG WATER DEPT | WA5322950 | 20,900 | Ground water | 8 | No available average above comparison levels |
| ELMA, CITY OF | WA5323100 | 6,638 | Ground water | 2 | No available average above comparison levels |
| EMERALD LAKE | WA5323294 | 331 | Ground water | 1 | No available average above comparison levels |
| ENUMCLAW WATER DEPARTMENT | WA5323600 | 23,276 | Ground water | 4 | No available average above comparison levels |
| EPHRATA WATER DEPARTMENT | WA5323650 | 8,718 | Ground water | 5 | No available average above comparison levels |
| EVERETT PUBLIC WORKS DEPT. CITY OF | WA5324050 | 215,774 | Surface water | 2 | No available average above comparison levels |
| EVERSON CITY OF | WA5324200 | 3,893 | Ground water | 1 | No available average above comparison levels |
| FAIRCHILD AIR FORCE BASE | WA5324350 | 9,544 | Ground water | 2 | Above an EPA comparison level |
| FERNDALE WA | WA5324850 | 19,305 | Ground water | 1 | No available average above comparison levels |
| FIFE DEPT OF PUBLIC WORKS | WA5325050 | 29,091 | Surface water purchased | 2 | No available average above comparison levels |
| FIRCREST CITY OF | WA5325150 | 7,927 | Ground water | 4 | No available average above comparison levels |
| FIRGROVE MUTUAL INC | WA5325200 | 36,168 | Surface water purchased | 13 | No available average above comparison levels |
| FORKS MUNICIPAL WATER DEPT | WA5326000 | 3,468 | Ground water | 2 | No available average above comparison levels |
| FRIDAY HARBOR TOWN OF | WA5326595 | 3,543 | Surface water | 1 | No available average above comparison levels |
| FRUITLAND MUTUAL WATER COMPANY | WA5326800 | 15,313 | Ground water | 4 | No available average above comparison levels |
| GIG HARBOR WATER DEPT | WA5327600 | 16,510 | Ground water | 6 | No available average above comparison levels |
| GOLD BAR CITY OF | WA5328300 | 2,745 | Ground water | 2 | No available average above comparison levels |
| GOLDENDALE CITY OF | WA5328450 | 4,314 | Ground water | 3 | No available average above comparison levels |
| GRANDVIEW CITY OF | WA5328970 | 11,010 | Ground water | 9 | No available average above comparison levels |
| GRANGER WATER DEPARTMENT | WA5329000 | 3,993 | Ground water | 1 | No available average above comparison levels |
| GRANITE FALLS CITY OF | WA5329050 | 5,349 | Surface water purchased | 1 | No available average above comparison levels |
| GRAYS HARBOR CO WATER DIST 2 | WA5329250 | 5,112 | Ground water | 1 | No available average above comparison levels |
| HARRINGTON CITY OF | WA5331450 | 650 | Ground water | 2 | No available average above comparison levels |
| HEIGHTS WATER | WA5332300 | 2,051 | Ground water | 1 | No available average above comparison levels |
| HI VALLEY VIEW | WA5300431 | 67 | Ground water | 1 | No available average above comparison levels |
| HIGHLINE WATER DISTRICT | WA5340650 | 100,170 | Surface water purchased | 3 | No available average above comparison levels |
| HOQUIAM WATER DEPARTMENT | WA5334350 | 11,456 | Surface water | 1 | No available average above comparison levels |
| HORIZONS WEST | WA5334375 | 3,454 | Ground water | 6 | No available average above comparison levels |
| IRVIN WATER DISTRICT #6 | WA5336050 | 4,150 | Ground water | 4 | No available average above comparison levels |
| ISSAQUAH WATER SYSTEM | WA5336350 | 43,584 | Surface water purchased | 4 | No available average above comparison levels |
| JBLM Lewis | WA5326050 | 35,414 | Ground water | 6 | Above an EPA comparison level |
| JBLM McChord Field | WA5352200 | 7,290 | Ground water | 7 | Above an EPA comparison level |
| KALAMA CITY OF | WA5337550 | 8,020 | Groundwater under influence of surface water | 1 | No available average above comparison levels |
| KELSO CITY OF | WA5338000 | 15,775 | Groundwater under influence of surface water | 1 | No available average above comparison levels |
| KENNEWICK CITY OF | WA5338100 | 118,164 | Surface water | 2 | Above an EPA comparison level |
| KENT WATER DEPARTMENT | WA5338150 | 166,421 | Surface water purchased | 6 | No available average above comparison levels |
| KING COUNTY WATER DISTRICT #125 | WA5341998 | 21,904 | Surface water purchased | 1 | No available average above comparison levels |
| KING COUNTY WATER DISTRICT #20 | WA5338950 | 48,469 | Surface water purchased | 1 | No available average above comparison levels |
| KING COUNTY WATER DISTRICT #49 | WA5339800 | 23,492 | Surface water purchased | 1 | No available average above comparison levels |
| KING COUNTY WATER DISTRICT #54 | WA5339950 | 5,373 | Surface water purchased | 1 | No available average above comparison levels |
| KING COUNTY WATER DISTRICT 119 | WA5341985 | 3,800 | Surface water purchased | 1 | No available average above comparison levels |
| KING COUNTY WATER DISTRICT NO 90 | WA5341150 | 20,100 | Surface water purchased | 2 | No available average above comparison levels |
| KIRKLAND CITY OF | WA5342250 | 69,243 | Surface water purchased | 1 | No available average above comparison levels |
| LACEY WATER DEPARTMENT | WA5343500 | 105,178 | Ground water | 12 | No available average above comparison levels |
| LAKE CHELAN RECLAMATION DISTRICT | WA5343783 | 6,798 | Surface water | 1 | No available average above comparison levels |
| LAKE CUSHMAN SYSTEM 5 | WA5303529 | 3,675 | Ground water | 7 | No available average above comparison levels |
| LAKE FOREST PARK WATER DISTRICT | WA5340950 | 3,171 | Ground water | 3 | No available average above comparison levels |
| LAKEHAVEN WATER AND SEWER DISTRICT | WA5341997 | 148,809 | Surface water purchased | 16 | No available average above comparison levels |
| LAKEWOOD WATER DISTRICT | WA5345550 | 82,425 | Ground water | 5 | Above an EPA comparison level |
| LIBERTY LAKE SEWER & WATER DISTRICT | WA5347150 | 14,500 | Ground water | 4 | No available average above comparison levels |
| LONG BEACH WATER DEPARTMENT | WA5348000 | 4,628 | Surface water | 1 | No available average above comparison levels |
| LONGVIEW WATER DEPARTMENT | WA5348100 | 57,617 | Ground water | 1 | No available average above comparison levels |
| LOST LAKE PROPERTY OWNERS ASSN | WA5348345 | 736 | Ground water | 1 | No available average above comparison levels |
| LUMMI TRIBAL WATER DISTRICT | 105300002 | 3,699 | Surface water purchased | 7 | No available average above comparison levels |
| LWWSD - SOUTH SHORE WATER SYSTEM | WA5395910 | 10,028 | Surface water | 1 | No available average above comparison levels |
| LYNDEN WATER DEPARTMENT | WA5349150 | 20,062 | Surface water | 1 | No available average above comparison levels |
| LYNNWOOD CITY OF | WA5349270 | 68,204 | Surface water purchased | 1 | No available average above comparison levels |
| Lake Meridian Water District | WA5341900 | 24,231 | Surface water purchased | 5 | No available average above comparison levels |
| MANCHESTER WATER DISTRICT | WA5350700 | 10,475 | Ground water | 8 | No available average above comparison levels |
| MARYSVILLE UTILITIES | WA5351900 | 88,582 | Surface water purchased | 5 | No available average above comparison levels |
| MCCORMICK WOODS | WA5340529 | 2,760 | Surface water purchased | 2 | No available average above comparison levels |
| MEDICAL LAKE CITY OF | WA5353400 | 4,982 | Ground water | 2 | No available average above comparison levels |
| MERCER ISLAND CITY OF | WA5353640 | 31,057 | Surface water purchased | 1 | No available average above comparison levels |
| MILTON CITY OF | WA5354950 | 8,078 | Ground water | 2 | No available average above comparison levels |
| MINTERBROOK | WA5354740 | 5,083 | Ground water | 13 | No available average above comparison levels |
| MODEL IRRIGATION DIST #18 | WA5355550 | 7,903 | Ground water | 7 | No available average above comparison levels |
| MODERN ELECTRIC WATER CO | WA5355600 | 18,487 | Ground water | 8 | No available average above comparison levels |
| MONROE WATER SYSTEM, WA | WA5355820 | 23,467 | Surface water purchased | 1 | No available average above comparison levels |
| MONTESANO CITY OF | WA5356000 | 6,204 | Ground water | 2 | No available average above comparison levels |
| MOSES LAKE CITY OF | WA5356300 | 32,428 | Ground water | 18 | Above an EPA comparison level |
| MOUNTAIN VIEW-EDGEWOOD WATER CO | WA5356820 | 9,680 | Ground water | 6 | No available average above comparison levels |
| MOUNTLAKE TERRACE CITY OF | WA5357250 | 26,402 | Surface water purchased | 1 | No available average above comparison levels |
| MOXEE WATER DEPARTMENT | WA5357300 | 5,599 | Ground water | 3 | No available average above comparison levels |
| MT. VISTA - DUNGENESS GOLF COURSE | 105388889 | 517 | Ground water | 2 | No available average above comparison levels |
| Mattawa City of | WA5352000 | 5,370 | Ground water | 1 | No available average above comparison levels |
| Mukilteo Water & Wastewater Distr | WA5357550 | 31,437 | Surface water purchased | 3 | No available average above comparison levels |
| NACHES TOWN OF | WA5358100 | 3,512 | Ground water | 2 | No available average above comparison levels |
| NAVAL AIR STATION/WHIDBEY ISLAND | WA5303420 | 16,595 | Surface water purchased | 1 | No available average above comparison levels |
| NAVAL BASE KITSAP AT BANGOR | WA5302714 | 16,828 | Ground water | 2 | No available average above comparison levels |
| NAVAL BASE KITSAP AT BREMERTON | WA5303468 | 11,792 | Surface water purchased | 1 | No available average above comparison levels |
| NE SAMMAMISH SEWER & WATER DISTRICT | WA5375265 | 9,702 | Ground water | 2 | No available average above comparison levels |
| NOB HILL WATER ASSOCIATION | WA5359700 | 38,050 | Ground water | 5 | No available average above comparison levels |
| NORTH BAINBRIDGE WATER CO | WA5359994 | 5,490 | Ground water | 1 | No available average above comparison levels |
| NORTH BEACH WATER | WA5363000 | 8,093 | Ground water | 2 | No available average above comparison levels |
| NORTH BEND, CITY OF | WA5360100 | 8,710 | Ground water | 2 | No available average above comparison levels |
| NORTH PENINSULA | WA5305122 | 16,449 | Ground water | 6 | No available average above comparison levels |
| NORTH PERRY AVE WATER DISTRICT | WA5360950 | 24,402 | Ground water | 9 | No available average above comparison levels |
| NORTHSHORE UTILITY DISTRICT | WA5340800 | 99,789 | Surface water purchased | 1 | No available average above comparison levels |
| North City Water District | WA5339600 | 32,847 | Surface water purchased | 1 | No available average above comparison levels |
| Northwest Water Assoc. Inc. | WA5362000 | 400 | Ground water | 2 | No available average above comparison levels |
| OAK HARBOR CITY OF | WA5362650 | 23,675 | Surface water purchased | 1 | No available average above comparison levels |
| OCEAN SHORES WATER DEPT | WA5363008 | 9,347 | Ground water | 1 | No available average above comparison levels |
| OLYMPIA CITY OF | WA5363450 | 126,966 | Ground water | 6 | No available average above comparison levels |
| OLYMPIC VIEW WATER & SEWER DISTRICT | WA5363600 | 17,784 | Surface water | 2 | No available average above comparison levels |
| OMAK CITY OF | WA5363750 | 4,940 | Ground water | 3 | No available average above comparison levels |
| ORCHARD AVENUE IRRIGATION DIST 6 | WA5364000 | 4,330 | Ground water | 2 | No available average above comparison levels |
| ORTING CITY OF | WA5364500 | 10,332 | Ground water | 5 | No available average above comparison levels |
| OTHELLO WATER DEPARTMENT | WA5364850 | 8,755 | Ground water | 7 | No available average above comparison levels |
| PACIFIC, CITY OF | WA5365300 | 7,925 | Ground water | 1 | No available average above comparison levels |
| PARKLAND LIGHT & WATER COMPANY | WA5366200 | 33,775 | Ground water | 5 | Above an EPA comparison level |
| PARKVIEW TERRACE | WA5366215 | 3,730 | Ground water | 5 | No available average above comparison levels |
| PASADENA PARK IRR DIST 17 | WA5366300 | 6,269 | Ground water | 4 | No available average above comparison levels |
| PASCO WATER DEPARTMENT | WA5366400 | 115,102 | Surface water | 2 | No available average above comparison levels |
| PATTISON | WA5366578 | 4,643 | Ground water | 7 | No available average above comparison levels |
| PEACOCK HILL | WA5366637 | 7,401 | Ground water | 26 | No available average above comparison levels |
| POINT EVANS | WA5368065 | 5,211 | Ground water | 8 | No available average above comparison levels |
| PORT ANGELES CITY OF | WA5368550 | 28,067 | Surface water | 1 | No available average above comparison levels |
| PORT ANGELES COMPOSITE | WA5343296 | 8,872 | Surface water | 5 | No available average above comparison levels |
| PORT TOWNSEND CITY OF | WA5369000 | 17,053 | Surface water | 1 | No available average above comparison levels |
| POULSBO CITY OF | WA5369150 | 18,400 | Ground water | 6 | No available average above comparison levels |
| PROSSER CITY OF | WA5369750 | 12,070 | Ground water | 1 | No available average above comparison levels |
| PUD #1 OF ASOTIN COUNTY | WA5393343 | 21,930 | Ground water | 6 | No available average above comparison levels |
| PULLMAN WATER DEPARTMENT CITY OF | WA5369880 | 31,315 | Ground water | 5 | No available average above comparison levels |
| PUYALLUP CITY OF | WA5370050 | 94,520 | Surface water purchased | 7 | No available average above comparison levels |
| Port Orchard Water | WA5368900 | 15,355 | Ground water | 4 | No available average above comparison levels |
| QUIMPER | WA5305783 | 14,548 | Ground water | 8 | No available average above comparison levels |
| QUINCY WATER DEPARTMENT CITY OF | WA5370450 | 8,415 | Ground water | 5 | No available average above comparison levels |
| QUISTORFF | WA5370550 | 1,113 | Ground water | 4 | Above an EPA comparison level |
| REDMOND WATER SYSTEM CITY OF | WA5371650 | 163,335 | Surface water purchased | 4 | No available average above comparison levels |
| RENTON CITY OF | WA5371850 | 108,091 | Ground water | 3 | No available average above comparison levels |
| RICHLAND CITY OF | WA5372250 | 106,499 | Surface water | 4 | No available average above comparison levels |
| RIDGEFIELD PUBLIC WORKS | WA5372400 | 21,225 | Ground water | 6 | No available average above comparison levels |
| Raymond Water Department | WA5371500 | 4,620 | Surface water | 1 | No available average above comparison levels |
| SALLAL WATER ASSOCIATION INC | WA5375560 | 6,600 | Ground water | 4 | No available average above comparison levels |
| SAMMAMISH PLATEAU WATER & SEWER | WA5340900 | 79,362 | Surface water purchased | 7 | Above an EPA comparison level |
| SEABECK | WA5303134 | 610 | Ground water | 1 | No available average above comparison levels |
| SEASCAPE WATER ASSOCIATION | WA5307095 | 28 | Ground water | 1 | No available average above comparison levels |
| SEATTLE PUBLIC UTILITIES | WA5377050 | 1,161,961 | Surface water | 2 | No available average above comparison levels |
| SELAH CITY OF | WA5377400 | 9,331 | Ground water | 3 | No available average above comparison levels |
| SEQUIM CITY OF | WA5377620 | 14,293 | Ground water | 3 | No available average above comparison levels |
| SEVEN LAKES WATER ASSOCIATION | WA5377660 | 5,823 | Ground water | 4 | No available average above comparison levels |
| SHELTER BAY COMMUNITY INC | WA5378155 | 2,212 | Surface water purchased | 1 | No available average above comparison levels |
| SHELTON CITY OF | WA5378170 | 15,089 | Ground water | 3 | No available average above comparison levels |
| SHOALWATER BAY | 105300019 | 898 | Ground water | 1 | No available average above comparison levels |
| SILVER LAKE WATER & SEWER DISTRICT | WA5379250 | 65,033 | Surface water purchased | 1 | No available average above comparison levels |
| SILVERDALE WATER DIST 16 | WA5379300 | 35,163 | Ground water | 10 | No available average above comparison levels |
| SKAGIT COUNTY PUD 1 JUDY RES | WA5379500 | 111,415 | Surface water | 1 | No available average above comparison levels |
| SKYWAY WATER & SEWER | WA5338800 | 12,036 | Surface water purchased | 3 | No available average above comparison levels |
| SNO PUD 1 - LAKE STEVENS | WA5380907 | 67,710 | Surface water purchased | 2 | No available average above comparison levels |
| SNOHOMISH CITY OF | WA5380915 | 16,367 | Surface water purchased | 2 | No available average above comparison levels |
| SNOQUALMIE PASS UTILITY DISTRICT | WA5381048 | 5,832 | Ground water | 1 | No available average above comparison levels |
| SNOQUALMIE WATER | WA5381080 | 20,222 | Ground water | 2 | No available average above comparison levels |
| SOOS CREEK WATER & SEWER DISTRICT | WA5340100 | 74,172 | Surface water purchased | 1 | No available average above comparison levels |
| SOUTHWOOD WATER SYSTEM | WA5382844 | 64,155 | Surface water purchased | 27 | Above an EPA comparison level |
| SPANAWAY WATER COMPANY | WA5382850 | 34,506 | Ground water | 10 | Above an EPA comparison level |
| SPO CO WATER DIST 3 SYS 2 | WA5393351 | 19,035 | Ground water | 5 | No available average above comparison levels |
| SPO CO WATER DIST 3 SYS 3 | WA5393353 | 3,768 | Ground water | 2 | No available average above comparison levels |
| SPO CO WATER DIST 3 SYS 4 | WA5393354 | 6,233 | Ground water | 4 | No available average above comparison levels |
| SPOKANE CITY OF | WA5383100 | 346,138 | Ground water | 6 | No available average above comparison levels |
| STANWOOD WATER DEPT CITY OF | WA5383650 | 17,586 | Ground water | 2 | No available average above comparison levels |
| STEILACOOM TOWN OF | WA5384000 | 8,545 | Ground water | 2 | No available average above comparison levels |
| STEVENS CO PUD - SUNCREST | WA5385202 | 7,484 | Ground water | 8 | No available average above comparison levels |
| STEVENS CO PUD - VALLEY | WA5305520 | 550 | Ground water | 2 | No available average above comparison levels |
| SULTAN WATER DEPARTMENT | WA5384770 | 8,424 | Surface water | 2 | No available average above comparison levels |
| SUMMIT WATER & SUPPLY CO | WA5385050 | 19,125 | Ground water | 7 | No available average above comparison levels |
| SUMNER CITY OF | WA5385120 | 16,438 | Ground water | 6 | No available average above comparison levels |
| SUQUAMISH | WA5386400 | 4,203 | Ground water | 4 | No available average above comparison levels |
| Snake River Housing Water System | WA5300710 | 3,036 | Ground water | 2 | No available average above comparison levels |
| TACOMA WATER DIVISION CITY OF | WA5386800 | 446,170 | Surface water | 3 | No available average above comparison levels |
| TOPPENISH WATER DEPARTMENT | WA5388850 | 8,950 | Ground water | 5 | No available average above comparison levels |
| TRENTWOOD IRRIGATION DISTRICT 3 | WA5389250 | 4,228 | Ground water | 4 | Above an EPA comparison level |
| TUKWILA WATER DEPARTMENT | WA5389500 | 36,298 | Surface water purchased | 1 | No available average above comparison levels |
| TULALIP BAY WATER DIST #1 | 105300003 | 5,968 | Surface water purchased | 1 | No available average above comparison levels |
| TUMWATER CITY OF | WA5389700 | 51,802 | Ground water | 5 | No available average above comparison levels |
| Tanglewilde-Thompson Place 600 | WA5304397 | 7,900 | Ground water | 1 | No available average above comparison levels |
| Tenino City of | WA5387400 | 3,336 | Ground water | 1 | No available average above comparison levels |
| UNION GAP WATER | WA5390250 | 6,433 | Ground water | 4 | No available average above comparison levels |
| UNION HILL WATER ASSOCIATION INC | WA5390260 | 8,720 | Ground water | 1 | No available average above comparison levels |
| VANCOUVER CITY OF | WA5391200 | 373,047 | Ground water | 10 | Above an EPA comparison level |
| VERA WATER & POWER | WA5391450 | 24,692 | Ground water | 6 | No available average above comparison levels |
| VINLAND | WA5391923 | 4,801 | Ground water | 3 | No available average above comparison levels |
| WALLA WALLA WATER DIVISION | WA5392500 | 42,959 | Surface water | 1 | No available average above comparison levels |
| WAPATO WATERWORKS | WA5392800 | 5,255 | Ground water | 3 | No available average above comparison levels |
| WARDEN CITY OF | WA5392850 | 4,674 | Ground water | 4 | No available average above comparison levels |
| WASHINGTON STATE UNIVERSITY | WA5393200 | 21,506 | Ground water | 4 | No available average above comparison levels |
| WASHOUGAL CITY OF | WA5393400 | 21,441 | Ground water | 3 | Above an EPA comparison level |
| WATER DISTRICT 19 | WA5338900 | 5,335 | Surface water | 5 | No available average above comparison levels |
| WENATCHEE CITY OF | WA5394350 | 43,690 | Ground water | 1 | No available average above comparison levels |
| WEST RICHLAND CITY OF | WA5394900 | 21,231 | Surface water purchased | 3 | No available average above comparison levels |
| WEST SEQUIM BAY INC | WA5354192 | 2,759 | Ground water | 1 | No available average above comparison levels |
| WESTPORT WATER DEPARTMENT | WA5395300 | 5,346 | Ground water | 3 | No available average above comparison levels |
| WHATCOM COUNTY WATER DIST 13 | WA5395914 | 795 | Ground water | 2 | No available average above comparison levels |
| WHITE SALMON CITY OF | WA5396350 | 4,077 | Surface water | 2 | No available average above comparison levels |
| WHITWORTH WATER DISTRICT 2 | WA5396601 | 26,883 | Ground water | 9 | No available average above comparison levels |
| WOODINVILLE WATER DISTRICT | WA5341600 | 66,699 | Surface water purchased | 1 | No available average above comparison levels |
| WOODLAND CITY OF | WA5398200 | 10,640 | Groundwater under influence of surface water | 1 | No available average above comparison levels |
| West Sound Utility District #1 | WA5302600 | 28,930 | Ground water | 9 | No available average above comparison levels |
| YAK CO - TERRACE HEIGHTS | WA5306029 | 8,410 | Ground water | 5 | No available average above comparison levels |
| YAKIMA WATER DIVISION CITY OF | WA5399150 | 112,858 | Surface water | 5 | No available average above comparison levels |
| YELM CITY OF | WA5399350 | 17,355 | Ground water | 2 | No available average above comparison levels |
How the count works
What is included
Each active community water system with enough required samples for a yearly average is counted once, even if it is linked with several ZIP codes. Private wells are excluded, and UCMR 5 did not comprehensively monitor every small system.