TapWaterGuide
Worldwide water safety reference
Safe Washington, United States · Last reviewed:

Is Tap Water Safe to Drink in Tacoma?

Yes, tap water in Tacoma is safe to drink and among the softest, cleanest big-city supplies in the country. Most of it flows from the protected Green River watershed in the Cascades, filtered since 2015 and fully EPA-compliant.

Hardness
Very soft
pH
7.5–8.2 (adjusted upward for corrosion control)
TDS
40–100 mg/L
EPA Status
Compliant
Soft
Moderate
Hard
Very Hard

Water Source

Tacoma Water, part of Tacoma Public Utilities, draws primarily from the Green River in a restricted-access Cascade watershed, treated at a filtration facility completed in 2015, supplemented by the North Fork wells and South Tacoma groundwater.

EPA Compliance Status

Meets all federal Safe Drinking Water Act standards.

Notable Contaminants & Context

  • No significant source-water concerns; the Green River watershed is closed to public access and heavily protected
  • Naturally very soft, low-alkalinity water can be slightly corrosive, so treatment adjusts pH to protect household plumbing
  • South Tacoma groundwater sits near legacy industrial areas and is monitored closely, with wellhead protections in place

Water Quality Data

Key contaminants detected vs. regulatory limits. All values from the most recent published report — Source: Tacoma Water 2024 Water Quality Report.

Contaminant Detected Limit Status
Chlorine (total) 0.8 mg/L 4.0 mg/L
Fluoride 0.72 mg/L 4.0 mg/L
Lead (90th percentile) 1.5 µg/L 15.0 µg/L
Nitrate (as N) 0.19 mg/L 10.0 mg/L
TTHM (Total Trihalomethanes) 14.8 µg/L 80.0 µg/L
HAA5 (Haloacetic Acids) 9.7 µg/L 60.0 µg/L

✓ = below limit   ⚠ = above health goal   ✗ = exceeds guideline

How It Compares

With its closed watershed and mountain snowmelt source, Tacoma's water resembles Seattle's famously clean Cedar River supply — soft, low-mineral, and needing modest treatment.

Tips

  • No softener or filter is needed; the water is naturally soft and clean
  • Older homes benefit from the standard flush-the-tap habit after long stagnation, as with any soft-water city
  • Tacoma Water publishes annual quality reports and watershed updates

Frequently Asked Questions

Sources & References

The safety rating and guidance on this page draw on the following sources. See our full methodology.