Water quality · Washington
Water quality in Washington
Of the 9 Washington ZIPs matched to an EPA SDWIS community water system, none reports a health-based violation in the last 3 years. 2 further ZIPs have no water-system record on zipradar yet. That is a gap in our records, not a sign that the water is untested. SDWIS reports the system serving the county, never an address-level test, and never private wells.
Last verified 2026-09-24 · methodology
Water quality by ZIP code in Washington
The largest community water system EPA lists for each ZIP's county, and its health-based violations in the last 3 years.
| ZIP | Largest system | Health-based violations |
|---|---|---|
| 98101SeattleKing County | SEATTLE PUBLIC UTILITIES | None |
| 98109Seattle (Queen Anne)King County | No record yet | |
| 98033KirklandKing County | KIRKLAND CITY OF | None |
| 99201SpokaneSpokane County | SPOKANE CITY OF | None |
| 98225BellinghamWhatcom County | BELLINGHAM-WATER DIVISION CITY OF | None |
| 98115Seattle (Wallingford)King County | SEATTLE PUBLIC UTILITIES | None |
| 98662Vancouver (WA)Clark County | VANCOUVER CITY OF | None |
| 98052Redmond (WA)King County | REDMOND WATER SYSTEM CITY OF | None |
| 98039Medina (WA)King County | No record yet | |
| 98004Bellevue (WA)King County | BELLEVUE CITY OF | None |
| 98112Seattle (Capitol Hill)King County | SEATTLE PUBLIC UTILITIES | None |
County-level figures from EPA SDWIS, joined to each ZIP by county. None of them is a measurement at a specific address.
What lands here
Pages show the largest community water system on record for the ZIP's county, its PWSID and population served, and its health-based and total violations in the last 3 years. Lead and copper sampling results are not shown; your utility's annual water quality report (CCR) has them.
Source & refresh
EPA SDWIS. Refreshed quarterly (federal mandate). Primary source →
Washington top concern
Wildfire (eastern), Cascadia seismic, coastal flood
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See Washington state page for the full state-level rollup across all 12 dimensions.
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