Is Sammamish, Washington tap water safe?
2 water systems report serving Sammamish. Your water depends on which one serves your address. Check your bill if unsure. This list is matched from the ZIP codes in this place, so it may include nearby systems.
C
Sammamish Plateau Water & Sewer
Serves 79,362 people · Surface water · Full report →
No health-based violations in the last 5 years; PFOA/PFOS average above the 4 ppt federal limit: PFOS; Other PFAS above 2024 limits (rule proposed for repeal): PFHxS, Hazard Index; Lead 90th percentile below the action level (2025).
A
Ne Sammamish Sewer & Water District
Serves 9,702 people · Groundwater · Full report →
No health-based violations in the last 5 years; 1 monitoring/reporting violation; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2023).