Water Quality in Indianapolis, IN

Indianapolis's water has very hard water (280 PPM) and PFAS above EPA limits (5 ppt). A water softener is recommended to protect plumbing and appliances. An activated carbon filter can reduce PFAS levels. Read below for a full breakdown.

Citizens Water · Source: White River + groundwater · Serves 887,642 residents

280
Hardness (PPM)
350
TDS (PPM)
1.1
Chlorine (mg/L)
5
PFAS (ppt)
4
Lead (ppb)
280 PPM 0 400 Very Hard
CONTAMINANT LEVELS Hardness 280 PPM TDS 350 PPM PFAS 5 ppt Lead 4 ppb Chlorine 1.1 mg/L Nitrate 3 mg/L

Hardness Scale: Where Indianapolis Falls

Soft 060120180250400+
Very hard waterLead concernsAging pipes

What Indianapolis's Water Means for Your Home

Indianapolis residents deal with some of the hardest municipal water in the country. At 280 PPM (undefined grains per gallon), the water contains high concentrations of dissolved calcium and magnesium picked up from underground limestone and mineral formations. This is not a safety issue. The minerals are safe to consume. But they create real, measurable costs for homeowners. Hard water at 280 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 Indianapolis homeowners discover this only after a water heater replacement or plumber visit.

PFAS contamination is a significant concern in Indianapolis. 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)280 PPM< 60 PPMNo federal limit⚠ Very Hard
Total Dissolved Solids350 PPM< 300 PPM500 PPM⚠ Elevated
PFAS (total)5 ppt4 ppt (EPA)4 ppt (2024)⚠ Above limit
Lead4 ppb0 ppb (no safe level)15 ppb (action level)✓ Low
Chlorine / Chloramine1.1 mg/LTaste threshold ~1.04.0 mg/L✓ Normal
Nitrate3 mg/L5 mg/L10 mg/L✓ OK

Recommendations for Indianapolis Homes

🧂 Water Softener
At 280 PPM (undefined GPG), Indianapolis's water is very 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 Indianapolis household of 2 to 4 people, a 48,000-grain softener is the right starting size.
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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 Indianapolis's Water Supply

Water Utility: Citizens Water

Water Source: White River + groundwater

Population Served: 887,642

Hardness: 280 PPM (undefined grains per gallon)

Water quality can vary by neighborhood and season. The values above represent typical averages reported by Citizens Water. 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 Indianapolis to Other Indiana Cities

Fort Wayne

274 PPM · Extremely Hard

Evansville

130 PPM · Hard

South Bend

276 PPM · Extremely Hard

Carmel

296 PPM · Extremely Hard

Fishers

251 PPM · Extremely Hard

Bloomington

140 PPM · Hard

Frequently Asked Questions About Indianapolis Water

Is Indianapolis tap water safe to drink?
Indianapolis'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 Indianapolis?
Yes. At 280 PPM (undefined GPG), Indianapolis's water is very 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 Indianapolis home with 2 to 4 residents, a 48,000-grain system is the most common starting size.
What water filter is best for Indianapolis?
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 Indianapolis's water come from?
Indianapolis's drinking water is sourced from White River + groundwater and treated by Citizens Water.
What is the hardness of Indianapolis water in grains per gallon?
Indianapolis's water hardness is undefined grains per gallon (GPG), which equals 280 parts per million (PPM). This is classified as very hard. Most water softener manufacturers recommend treatment above 7 GPG. To convert: 1 GPG = 17.1 PPM.
Does Indianapolis water damage tankless water heaters?
Yes. Most tankless water heater manufacturers recommend water hardness below 7 to 11 GPG (120 to 188 PPM). At undefined GPG, Indianapolis'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 Indianapolis water safe for babies and infants?
Indianapolis'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 Indianapolis household per year?
At 280 PPM, hard water costs the average Indianapolis 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 Indianapolis 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 Citizens Water Consumer Confidence Report. Hardness and contaminant levels represent typical average values and may vary by neighborhood and season. Last updated: 2026-02-12.