Water Quality in Spokane, WA

Spokane's water has PFAS above EPA limits (5 ppt). An activated carbon filter can reduce PFAS levels. Read below for a full breakdown.

City of Spokane · Source: Spokane-Rathdrum Aquifer · Serves 228,989 residents

104
Hardness (PPM)
156
TDS (PPM)
0.7
Chlorine (mg/L)
5
PFAS (ppt)
1
Lead (ppb)
104 PPM 0 400 Moderately Hard
CONTAMINANT LEVELS Hardness 104 PPM TDS 156 PPM PFAS 5 ppt Lead 1 ppb Chlorine 0.7 mg/L Nitrate 1 mg/L

Hardness Scale: Where Spokane Falls

Soft 060120180250400+
Moderately hardExcellent taste

One of the largest and cleanest aquifers in the western US.

What Spokane's Water Means for Your Home

Spokane's water is moderately hard at 104 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 Spokane, focus on contaminant filtration rather than softening.

PFAS contamination is a significant concern in Spokane. At 5 parts per trillion, levels exceed the EPA's 2024 maximum contaminant level of 4 ppt. PFAS are synthetic chemicals that do not break down in the environment or the human body, which is why they are called "forever chemicals." Long-term exposure has been associated with increased cancer risk, thyroid disruption, and immune system effects. A whole-house activated carbon filter or point-of-use reverse osmosis system can reduce PFAS to safe levels. Look for NSF P473 certification when comparing products.

ContaminantDetectedHealth GuidelineLegal LimitStatus
Hardness (as CaCO₃)104 PPM< 60 PPMNo federal limit✓ OK
Total Dissolved Solids156 PPM< 300 PPM500 PPM✓ OK
PFAS (total)5 ppt4 ppt (EPA)4 ppt (2024)⚠ Above limit
Lead1 ppb0 ppb (no safe level)15 ppb (action level)✓ Low
Chlorine / Chloramine0.7 mg/LTaste threshold ~1.04.0 mg/L✓ Normal
Nitrate1 mg/L5 mg/L10 mg/L✓ OK

Recommendations for Spokane Homes

🔄 Salt-Free Conditioner (Optional)
At 104 PPM, Spokane's water is moderately hard. Scale buildup is slow but noticeable over years, especially in tankless water heaters. A salt-free conditioner is a low-maintenance option if you want to extend appliance life.
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🔬 Activated Carbon Filter for PFAS
PFAS detected at 5 ppt, above the EPA maximum contaminant level of 4 ppt. PFAS are linked to cancer, thyroid disease, and immune system effects with long-term exposure. A whole-house granular activated carbon (GAC) filter or a point-of-use reverse osmosis system can reduce PFAS. Look for NSF P473 certification, which specifically tests for PFAS removal.
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About Spokane's Water Supply

Water Utility: City of Spokane

Water Source: Spokane-Rathdrum Aquifer

Population Served: 228,989

Hardness: 104 PPM (6.1 grains per gallon)

Water quality can vary by neighborhood and season. The values above represent typical averages reported by City of Spokane. 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 Spokane to Other Washington Cities

Seattle

20 PPM · Soft

Tacoma

21 PPM · Slightly Hard

Vancouver

13 PPM · Soft

Bellevue

26 PPM · Slightly Hard

Kent

16 PPM · Soft

Everett

26 PPM · Slightly Hard

Frequently Asked Questions About Spokane Water

Is Spokane tap water safe to drink?
Spokane's water meets EPA legal standards for drinking water safety. However, legal limits and health-optimal levels are different things. PFAS levels exceed the 2024 EPA health standard, which is a concern for long-term exposure. 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 Spokane?
At 104 PPM, Spokane's water is moderately hard. Some homeowners at this level do not notice problems, while others see spotting on glassware, film on shower doors, or reduced soap lathering. Homes with tankless water heaters at this hardness level should strongly consider at least a salt-free conditioner, as scale buildup inside the heat exchanger can void the warranty. For other homes, it depends on your sensitivity and fixtures.
What water filter is best for Spokane?
The best filter depends on which contaminants you want to address. For PFAS, look for a filter with NSF P473 certification. Granular activated carbon (GAC) and reverse osmosis systems are both effective. Standard carbon pitcher filters may not remove PFAS adequately. See our softener vs. filter guide to understand the difference between these categories.
Where does Spokane's water come from?
Spokane's drinking water is sourced from Spokane-Rathdrum Aquifer and treated by City of Spokane. One of the largest and cleanest aquifers in the western US..
What is the hardness of Spokane water in grains per gallon?
Spokane's water hardness is 6.1 grains per gallon (GPG), which equals 104 parts per million (PPM). This is classified as moderately hard. To convert: 1 GPG = 17.1 PPM.
Does Spokane water damage tankless water heaters?
At 6.1 GPG, Spokane'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 Spokane water safe for babies and infants?
Spokane'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 City of Spokane Consumer Confidence Report. Hardness and contaminant levels represent typical average values and may vary by neighborhood and season. Last updated: 2026-02-12.