Water Quality in Federal Way, WA

Federal Way's water quality is good overall. Hardness is low at 18 PPM, and no contaminants exceed health guidelines. Most homes here do not need a water softener.

Lakehaven Water District · Source: Tacoma Water (Green River), Lakehaven Wells · Serves 101,030 residents

18
Hardness (PPM)
48
TDS (PPM)
0.9
Chlorine (mg/L)
3
PFAS (ppt)
1
Lead (ppb)
18 PPM 0 400 Slightly Hard
CONTAMINANT LEVELS Hardness 18 PPM TDS 48 PPM PFAS 3 ppt Lead 1 ppb Chlorine 0.9 mg/L Nitrate 1 mg/L

Hardness Scale: Where Federal Way Falls

Soft 060120180250400+
Generally good quality

Federal Way blends Tacoma Water supply with local wells. Water is soft from Puget Sound glacial geology.

What Federal Way's Water Means for Your Home

Federal Way's water is slightly hard at 18 PPM. At this level, hard water is not a significant concern for most households. Scale buildup is minimal, and a water softener would provide little measurable benefit. If you are considering water treatment in Federal Way, focus on contaminant filtration rather than softening.

Beyond hardness, Federal Way's water quality is generally within EPA guidelines for regulated contaminants. Chlorine is present at 0.9 mg/L as a disinfectant residual, which is normal for municipal water systems. If you notice a pool-like taste or experience dry skin, a whole-house carbon filter is the most common and affordable solution. For homeowners who want to understand the full picture, requesting your utility's annual Consumer Confidence Report provides neighborhood-level data.

ContaminantDetectedHealth GuidelineLegal LimitStatus
Hardness (as CaCO₃)18 PPM< 60 PPMNo federal limit✓ OK
Total Dissolved Solids48 PPM< 300 PPM500 PPM✓ OK
PFAS (total)3 ppt4 ppt (EPA)4 ppt (2024)✓ OK
Lead1 ppb0 ppb (no safe level)15 ppb (action level)✓ Low
Chlorine / Chloramine0.9 mg/LTaste threshold ~1.04.0 mg/L✓ Normal
Nitrate1 mg/L5 mg/L10 mg/L✓ OK

Good news for ${esc(c.city)} residents. Your water quality is generally good. Most homes in this area do not need a water softener. If you have concerns about lead (especially in buildings constructed before 1986) or chlorine taste, a point-of-use filter is the most practical and cost-effective solution.

About Federal Way's Water Supply

Water Utility: Lakehaven Water District

Water Source: Tacoma Water (Green River), Lakehaven Wells

Population Served: 101,030

Hardness: 18 PPM (1.1 grains per gallon)

Water quality can vary by neighborhood and season. The values above represent typical averages reported by Lakehaven Water District. To get exact numbers for your address, request a copy of the most recent Consumer Confidence Report (CCR) from your utility, or have your water independently tested.

Compare Federal Way to Other Washington Cities

Frequently Asked Questions About Federal Way Water

Is Federal Way tap water safe to drink?
Federal Way's water meets EPA legal standards for drinking water safety. However, legal limits and health-optimal levels are different things. Review the contaminant table above for specific numbers and how they compare to both legal limits and health guidelines.
Do I need a water softener in Federal Way?
No. At 18 PPM, Federal Way's water is very soft. A water softener would provide no benefit here. Focus on filtration if you have specific contaminant concerns.
What water filter is best for Federal Way?
The best filter depends on which contaminants you want to address. See our softener vs. filter guide to understand the difference between these categories.
Where does Federal Way's water come from?
Federal Way's drinking water is sourced from Tacoma Water (Green River), Lakehaven Wells and treated by Lakehaven Water District. Federal Way blends Tacoma Water supply with local wells. Water is soft from Puget Sound glacial geology.
What is the hardness of Federal Way water in grains per gallon?
Federal Way's water hardness is 1.1 grains per gallon (GPG), which equals 18 parts per million (PPM). This is classified as slightly hard. To convert: 1 GPG = 17.1 PPM.
Does Federal Way water damage tankless water heaters?
At 1.1 GPG, Federal Way's water is unlikely to cause significant issues for tankless water heaters. However, if you notice reduced flow or efficiency over time, scale buildup could be a factor. Annual flushing with vinegar is good maintenance regardless of hardness.
Is Federal Way water safe for babies and infants?
Federal Way's water meets all EPA safety standards and is generally considered safe for preparing infant formula. The hardness minerals (calcium and magnesium) are not harmful. If your home has older plumbing, running cold water for 30 seconds before use is a good precaution to flush any lead from pipes.

Data sources. Water quality data compiled from EPA SDWIS, EWG Tap Water Database, USGS water hardness studies, and the Lakehaven Water District Consumer Confidence Report. Hardness and contaminant levels represent typical average values and may vary by neighborhood and season. Last updated: 2026-02-12.