Hard water in Peoria, IL
Reported by IL American-Peoria · August 2025
- IL typical
- 139 mg/L
- EPA health violations since 2016
- 0
- Softener for 3 people
- 32k grain
- Data
- Utility report
Tap water in Peoria has about 272 mg/L of hardness, which is 15.9 grains per gallon. On the USGS scale that counts as very hard. The number comes from IL American-Peoria, dated August 2025.
Peoria sits 133 mg/L above the typical Illinois figure of 139. Of the 10 nearest cities we track, 4 have softer water and 6 have harder. The range nearby runs from 54 mg/L in Kewanee to 401 in Canton.
What 272 mg/L means at home
Scale forms fast here. Kettles and coffee makers need regular descaling, and showerheads clog unless you clean them.
Tank water heaters collect mineral sediment that insulates the water from the burner, so flushing the tank matters more than usual.
Dishes and glass shower doors spot easily. Soap scum and a dull film on hair or laundry are common complaints.
Hardness is not a health problem, and EPA sets no limit for it. It is a matter of scale and soap.
What to do about it
At 272 mg/L most of the trouble is scale, and only a few things deal with it.
Ion-exchange water softener
The standard whole-house fix. It swaps calcium and magnesium for sodium or potassium and needs salt plus a drain. Size it with the calculator below.
Salt-free conditioner
No salt and no drain line. It changes how minerals form scale instead of removing them, so water still tests hard.
Reverse osmosis or carbon filter
Under-sink reverse osmosis removes minerals from drinking water only. Plain carbon filters improve taste but do not soften.
3 people × 75 gallons a day × 15.9 gpg = 3,586 grains a day. A 32,000-grain unit regenerates about every 8 days.
EPA record for Peoria's water system
No health-based violations since 2016
Serves about 137,575 people from surface water.
- Health-based
- 0
- Monitoring or reporting
- 0
- Open now
- 0
Health-based means a contaminant above its legal limit or a missed treatment step. Monitoring and reporting violations are late or missing tests and notices. Source: EPA ECHO, 2026Q3 export, violations with periods starting 2016 or later. Full EPA record.
Questions
Is Peoria water hard?
Yes. It measures about 272 mg/L (15.9 grains per gallon), which the USGS classes as very hard.
What is the water hardness in Peoria in grains per gallon?
About 15.9 gpg. One grain per gallon equals 17.1 mg/L, so 272 mg/L divided by 17.1 gives 15.9.
What size water softener do I need in Peoria?
For 3 people using 75 gallons each per day, 15.9 gpg works out to about 3,586 grains a day. A 32,000-grain softener covers that with a regeneration about every 8 days.
Has the Peoria water system had EPA violations?
EPA records show no health-based violations for IL American-Peoria since 2016.
Nearby cities
- East Peoria361 mg/LVery hard
- Bartonville283 mg/LVery hard
- Washington230 mg/LVery hard
- Morton170 mg/LHard
- Pekin361 mg/LVery hard
- Canton401 mg/LVery hard
- Normal327 mg/LVery hard
- Kewanee54 mg/LSoft
- Bloomington89 mg/LModerately hard
- Galesburg331 mg/LVery hard
Hardness data: TapWaterData US Water Hardness (utility report, August 18, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.