Safe
Washington, United States
Is Tap Water Safe to Drink in Seattle?
Yes, tap water in Seattle is safe to drink and consistently ranks among the best in the U.S., sourced from protected forested watersheds in the Cascade foothills.
Hardness
Very soft
pH
7.5–8.0 (adjusted for corrosion control)
TDS
ranges 30–50 ppm
EPA Status
Compliant
Water Source
Seattle Public Utilities draws from the Cedar River and South Fork Tolt River watersheds, both largely protected from development, allowing minimal treatment before distribution.
EPA Compliance Status
Meets all federal Safe Drinking Water Act standards; the Cedar River source qualifies for an EPA filtration avoidance determination due to source water quality.
Notable Contaminants & Context
- •No significant source-water concerns given the protected watersheds
- •Some older homes have legacy lead service lines; the utility adjusts water chemistry for corrosion control
How It Compares
Like Boston, NYC, and Portland, Seattle's protected watershed sourcing lets much of its supply skip full filtration — a mark of unusually clean source water.
Tips
- •Seattle's tap water is genuinely excellent straight from the tap
- •No need for bottled water around the city
- •Seattle Public Utilities publishes detailed annual water quality reports