Water Quality: Seattle, WA
7 water systems • 1,160,858 people served
Some ConcernsWater Quality Summary
Seattle is served by 7 public water systems with a combined service population of 1,160,858 people, and has 28 EPA Safe Drinking Water Act violations on record. Critically, 3 of those are health-based violations, meaning one or more contaminants were detected above EPA-established safe levels — a serious public health concern. Seattle's violation count is 83% below the national average for Washington. Contaminants associated with violations include Fecal Coliform.
Contaminants Found
Indicates direct fecal contamination; associated with diarrhea, cramps, nausea, and potential severe illness.
Common source: Human and animal fecal waste
EPA limit: Zero tolerance (any positive triggers violations)
Water Systems Serving Seattle
| System Name | PWSID | Source | Population | Violations |
|---|---|---|---|---|
| SEATTLE PUBLIC UTILITIES | WA5377050 | Surface Water | 1,091,904 | 3 |
| KING COUNTY WATER DISTRICT #20 | WA5338950 | Surface Water | 38,974 | 0 |
| KING COUNTY WATER DISTRICT #125 | WA5341998 | Surface Water | 17,546 | 2 |
| SKYWAY WATER & SEWER | WA5338800 | Surface Water | 12,036 | 6 |
| Ravenwing Ranch | WA53AB782 | Groundwater | 250 | 0 |
| CHERRYWOOD MOBILE HOME MANOR | WA5312630 | Groundwater | 120 | 17 |
| Majestic Oaks Water System | WA5355860 | Groundwater | 28 | 0 |
Concerned About Your Water?
A home water filter can remove common contaminants. NSF-certified filters are tested against EPA standards.
Consider a reverse osmosis system for comprehensive filtration or a carbon filter for basic improvement.
Other Cities in Washington
Data Sources
Drinking water violation data from the EPA Safe Drinking Water Information System (SDWIS). Data includes all recorded violations for active community water systems.