Tapcensus

Water quality in Sammamish, Washington

Sammamish is in King County. 217 active public water systems serve the county; 86 had an EPA violation in the past three years.

Most likely your provider

Sammamish Plateau Water & Sewer WA5340900 · Community water system · Surface water purchased
Serves 79,362 people Rules violated, past 3 years 0 Last sanitary survey Apr 16, 2025 Distance 1.4 mi

Your location is within the outer bounds of this system's EPA service area.

View system details EPA facility report

Other community water systems in King County

155 systems, nearest first
SystemServesStatusRules violated, 3 yrDistance
The Meadows Water System LLC
 127 0 2.9 mi
NE Sammamish Sewer & Water District
 9,702 0 3.3 mi
Issaquah Water System
 43,584 0 4.0 mi
Edgehill Water Assn
 109 2 4.0 mi
Ames Lake Water Assoc INC
 3,224 1 5.0 mi
Preston Industrial Park Water Assn
 930 0 5.0 mi
Union Hill Water Association INC
 8,720 0 5.3 mi
Bellevue City of
 321,349 0 5.6 mi
King County Water District #117
 95 0 5.6 mi
Redmond Water System City of
 163,335 0 6.7 mi
Fall City Water Dist. #127
 2,987 1 7.0 mi
King County Water District #123
 242 0 7.1 mi
Dawnbreaker Water Association
 168 1 7.1 mi
Coal Creek Utility District
 15,989 0 7.1 mi
Issaquah Valley Water Assn #1
 80 1 7.1 mi
Lake Alice Water Association
 90 0 7.5 mi
Carnation Water System City of
 2,400 1 7.6 mi
Beaux Arts Water Department
 345 1 7.6 mi
Alpine Mobile Manor
 45 3 7.7 mi
Four Creeks Ranch Water System
 150 1 8.0 mi
King County Water District NO 90
 20,100 1 8.0 mi
Twenty-Three 800 Tiger Mountain
 129 0 8.3 mi
Spring Glen Association
 273 0 8.3 mi
Fall City Water Dist.(spring Hill)
 57 1 8.7 mi
Mercer Island City of
 31,057 0 9.1 mi
All 156 community water systems in King County
Non-community systems in King County (61: schools, campgrounds, workplaces, restaurants)

These systems serve places you visit rather than homes.

SystemServesStatusRules violated, 3 yrUnresolved
Red Fall Quick Stop
 30 0 0
Cougar Mtn. Park WT Supply Sys.
 25 0 0
Tall Chief Resort
 136 0 0
Issaquah Christian Church
 42 0 0
Cougar / Squak Corridor
 4 0 0
Carnation Farms
 179 0 0
Blue Sky RV Park
 68 0 0
Fraternity Snoqualmie
 34 0 0
Camp River Ranch
 76 0 0
Green Bobbie
 80 0 0
Port of Seattle/seatac Airport
 49,483 0 0
Cedar Grove Water Company
 30 1 0
St. Sava Serbian Orthodox Church
 32 1 0
Washington Cathedral
 1,001 0 0
Shyne School Water System
 79 1 0
Cedar Grove Composting Water System
 50 2 0
Rio Vista
 36 0 0
Rainier Christian School
 150 1 1
Lions Memorial Youth Camp
 61 0 0
Red Dog Saloon Water System
 30 0 0
Snoqualmie Valley Land Company INC
 80 1 1
Awareness Water System
 76 0 0
Mount SI Motel
 45 0 0
King County Shooting Sports Park
 27 0 0
Cedar Falls Supply
 184 1 0
Valleyview Christian Church
 88 0 0
Rogers Group Properties I LLC
 570 1 0
Rainbow Trout Club Homeowners Assoc
 30 0 0
Kanaskat-Palmer State Park
 543 0 0
Soos Creek Salmon Hatchery
 73 0 0
Green River Gorge Resort
 104 0 0
Cascade View Rodger Scott Water
 25 1 0
Boondocks Tavern
 30 0 0
Flaming Geyser State Park
 1,947 0 0
Middle Fork Campground #2
 54 0 0
Vashon Island Golf & Country Club
 226 0 0
Wabash Pres. Church Supply #1
 71 0 0
Camp Burton Conference Center
 39 0 0
Danner Corp
 50 0 0
Tinkham Campground
 57 0 0
Montessori Spring Valley Supply
 121 1 0
Harbor Heights Water
 25 0 0
Sunwater Beach
 17 1 0
Paradise Cove Water System
 17 0 0
Camp Sealth
 62 1 0
Morningside Farm Water System
 65 0 0
Asahel Curtis Picnic Ground East
 80 1 0
Asahel Curtis Picnic Ground West
 80 1 0
Denny Creek Campground
 155 0 0
Money Creek Campground
 61 0 0
All non-community systems
About this data

Water systems are matched to King County, nearest to Sammamish first. Your exact provider depends on your address and connection; the largest community water system in a county is usually the city or town utility. Distances are measured to the centre of the service area EPA publishes for the system.

Town locations and ZIP code areas come from U.S. Census Bureau 2020 files.

Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Washington records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet. Retrieved from ECHO on Oct 11, 2026.