Water Quality in Eau Claire, WI

Eau Claire's water has very hard water (265 PPM). A water softener is recommended to protect plumbing and appliances. Read below for a full breakdown.

Eau Claire Water Utility · Source: Eau Claire River wells · Serves 69,421 residents

265
Hardness (PPM)
376
TDS (PPM)
0.9
Chlorine (mg/L)
4
PFAS (ppt)
2
Lead (ppb)
265 PPM 0 400 Extremely Hard
CONTAMINANT LEVELS Hardness 265 PPM TDS 376 PPM PFAS 4 ppt Lead 2 ppb Chlorine 0.9 mg/L Nitrate 5 mg/L

Hardness Scale: Where Eau Claire Falls

Soft 060120180250400+
Extremely hard water

Eau Claire's Chippewa Valley wells produce hard water from sandstone and glacial drift.

What Eau Claire's Water Means for Your Home

Eau Claire residents deal with some of the hardest municipal water in the country. At 265 PPM (15.5 grains per gallon), the water contains high concentrations of dissolved calcium and magnesium picked up from the regional geology as surface water is treated and distributed. This is not a safety issue. The minerals are safe to consume. But they create real, measurable costs for homeowners. Hard water at 265 PPM costs the average household $800 to $1,200 per year in hidden expenses, including higher energy bills from scale-insulated water heaters, increased soap and detergent usage, and premature appliance failure. Many Eau Claire homeowners discover this only after a water heater replacement or plumber visit.

Beyond hardness, Eau Claire'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)265 PPM< 60 PPMNo federal limit⚠ Very Hard
Total Dissolved Solids376 PPM< 300 PPM500 PPM⚠ Elevated
PFAS (total)4 ppt4 ppt (EPA)4 ppt (2024)✓ OK
Lead2 ppb0 ppb (no safe level)15 ppb (action level)✓ Low
Chlorine / Chloramine0.9 mg/LTaste threshold ~1.04.0 mg/L✓ Normal
Nitrate5 mg/L5 mg/L10 mg/L✓ OK

Recommendations for Eau Claire Homes

🧂 Water Softener
At 265 PPM (15.5 GPG), Eau Claire's water is extremely hard. Scale will accumulate in pipes, water heaters, and on fixtures. A salt-based ion exchange softener removes the calcium and magnesium causing the problem. For a typical Eau Claire household of 2 to 4 people, a 48,000-grain softener is the right starting size.
Learn more about this solution →

About Eau Claire's Water Supply

Water Utility: Eau Claire Water Utility

Water Source: Eau Claire River wells

Population Served: 69,421

Hardness: 265 PPM (15.5 grains per gallon)

Water quality can vary by neighborhood and season. The values above represent typical averages reported by Eau Claire Water Utility. 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 Eau Claire to Other Wisconsin Cities

Milwaukee

140 PPM · Hard

Madison

312 PPM · Extremely Hard

Green Bay

166 PPM · Hard

Kenosha

143 PPM · Hard

Racine

139 PPM · Hard

Appleton

304 PPM · Extremely Hard

Frequently Asked Questions About Eau Claire Water

Is Eau Claire tap water safe to drink?
Eau Claire'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 Eau Claire?
Yes. At 265 PPM (15.5 GPG), Eau Claire's water is extremely hard. Without a softener, expect visible scale buildup on faucets and shower heads, reduced water heater efficiency (15 to 25 percent higher energy costs), spotted dishes and glassware, and soap that does not lather well. A salt-based water softener is the standard solution. For a typical Eau Claire home with 2 to 4 residents, a 48,000-grain system is the most common starting size.
What water filter is best for Eau Claire?
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 Eau Claire's water come from?
Eau Claire's drinking water is sourced from Eau Claire River wells and treated by Eau Claire Water Utility. Eau Claire's Chippewa Valley wells produce hard water from sandstone and glacial drift..
What is the hardness of Eau Claire water in grains per gallon?
Eau Claire's water hardness is 15.5 grains per gallon (GPG), which equals 265 parts per million (PPM). This is classified as extremely hard. Most water softener manufacturers recommend treatment above 7 GPG. To convert: 1 GPG = 17.1 PPM.
Does Eau Claire water damage tankless water heaters?
Yes. Most tankless water heater manufacturers recommend water hardness below 7 to 11 GPG (120 to 188 PPM). At 15.5 GPG, Eau Claire's water exceeds this threshold. Scale buildup inside the heat exchanger reduces efficiency and can void the manufacturer's warranty. A water softener installed upstream of the tankless heater is the standard solution.
Is Eau Claire water safe for babies and infants?
Eau Claire'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.
How much does hard water cost a Eau Claire household per year?
At 265 PPM, hard water costs the average Eau Claire household an estimated $800 to $1,200 per year in hidden costs. This includes 15 to 25 percent higher water heating bills from scale insulation, 50 to 75 percent more soap and detergent usage, shorter appliance lifespans (water heaters, dishwashers, washing machines), and increased plumbing maintenance. A water softener typically costs $600 to $1,500 installed and $50 to $100 per year in salt, which means most Eau Claire households see a return on investment within 1 to 2 years.

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