Water Quality in Boise, ID

Boise's water quality is good overall. Hardness is low at 110 PPM, and no contaminants exceed health guidelines. Most homes here do not need a water softener.

Suez Water Idaho · Source: Boise River + groundwater · Serves 228,959 residents

110
Hardness (PPM)
170
TDS (PPM)
0.4
Chlorine (mg/L)
3
PFAS (ppt)
1
Lead (ppb)
110 PPM 0 400 Hard
CONTAMINANT LEVELS Hardness 110 PPM TDS 170 PPM PFAS 3 ppt Lead 1 ppb Chlorine 0.4 mg/L Nitrate 3 mg/L

Hardness Scale: Where Boise Falls

Soft 060120180250400+
Hard waterLow chlorine (good taste)

What Boise's Water Means for Your Home

Boise's water is hard at 110 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 Boise, focus on contaminant filtration rather than softening.

Beyond hardness, Boise's water quality is generally within EPA guidelines for regulated contaminants. Chlorine is present at 0.4 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)110 PPM< 60 PPMNo federal limit✓ OK
Total Dissolved Solids170 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 / Chloramine0.4 mg/LTaste threshold ~1.04.0 mg/L✓ Normal
Nitrate3 mg/L5 mg/L10 mg/L✓ OK

Recommendations for Boise Homes

🔄 Salt-Free Conditioner (Optional)
At 110 PPM, Boise'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.
Learn more about this solution →

About Boise's Water Supply

Water Utility: Suez Water Idaho

Water Source: Boise River + groundwater

Population Served: 228,959

Hardness: 110 PPM (undefined grains per gallon)

Water quality can vary by neighborhood and season. The values above represent typical averages reported by Suez Water Idaho. 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 Boise to Other Idaho Cities

Pocatello

86 PPM · Moderately Hard

Meridian

82 PPM · Moderately Hard

Nampa

62 PPM · Moderately Hard

Idaho Falls

91 PPM · Moderately Hard

Frequently Asked Questions About Boise Water

Is Boise tap water safe to drink?
Boise'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 Boise?
At 110 PPM, Boise'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 Boise?
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 Boise's water come from?
Boise's drinking water is sourced from Boise River + groundwater and treated by Suez Water Idaho.
What is the hardness of Boise water in grains per gallon?
Boise's water hardness is undefined grains per gallon (GPG), which equals 110 parts per million (PPM). This is classified as hard. To convert: 1 GPG = 17.1 PPM.
Does Boise water damage tankless water heaters?
At undefined GPG, Boise'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 Boise water safe for babies and infants?
Boise'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 Suez Water Idaho Consumer Confidence Report. Hardness and contaminant levels represent typical average values and may vary by neighborhood and season. Last updated: 2026-02-12.