How hard is the water in Elmhurst, IL?

Tap water hardness
110mg/L
6.4gpg
Moderately hard

Reported by Elmhurst · September 2025

IL typical
139 mg/L
EPA health violations since 2016
0
Softener for 3 people
24k grain
Data
Utility report

The water in Elmhurst carries roughly 110 mg/L of dissolved calcium and magnesium, or 6.4 grains per gallon. That is moderately hard water. The number comes from Elmhurst, dated September 2025.

Elmhurst on the hardness scale, with nearby cities
060120180240300360+IL typical 139Villa Park: 99 mg/LVilla Park 99Melrose Park: 103 mg/LMelrose Park 103Berkeley: 104 mg/LBerkeley 104Northlake: 104 mg/LNorthlake 104Bellwood: 104 mg/LBellwood 104Bensenville: 104 mg/LBensenville 104Franklin Park: 104 mg/LFranklin Park 104Maywood: 229 mg/LMaywood 229Lombard: 287 mg/LLombard 287Addison: 287 mg/LAddison 287Elmhurst 110mg/L as calcium carbonate060120180240300360+IL 139Villa Park: 99 mg/LVilla Park 99Berkeley: 104 mg/LBerkeley 104Northlake: 104 mg/LNorthlake 104Bellwood: 104 mg/LBellwood 104Lombard: 287 mg/LLombard 287Addison: 287 mg/LAddison 287110 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

At 110 mg/L, Elmhurst is 29 mg/L below the typical Illinois figure of 139. Of the 10 nearest cities we track, 7 have softer water and 3 have harder. The range nearby runs from 99 mg/L in Villa Park to 287 in Lombard.

What 110 mg/L means at home

You may see faint white spots on glasses and shower doors after the water dries.

Scale builds up slowly. A kettle or coffee maker needs descaling now and then, maybe every few months.

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

Optional. Plenty of households at this level live with it and descale the kettle now and then.

Water softener

Worth a look if spots on glass bother you, or if your tankless water heater manual asks for softer water.

Carbon filter

Improves taste and removes chlorine. It leaves calcium and magnesium in place.

Softener size for Elmhurst

3 people × 75 gallons a day × 6.4 gpg = 1,447 grains a day. A 24,000-grain unit regenerates about every 16 days.

Size it for your household

EPA record for Elmhurst's water system

Elmhurst · PWSID IL0430350

No health-based violations since 2016

Serves about 45,000 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 Elmhurst water hard?

Somewhat. It measures about 110 mg/L (6.4 grains per gallon), which the USGS classes as moderately hard.

What is the water hardness in Elmhurst in grains per gallon?

About 6.4 gpg. One grain per gallon equals 17.1 mg/L, so 110 mg/L divided by 17.1 gives 6.4.

What size water softener do I need in Elmhurst?

For 3 people using 75 gallons each per day, 6.4 gpg works out to about 1,447 grains a day. A 24,000-grain softener covers that with a regeneration about every 16 days.

Has the Elmhurst water system had EPA violations?

EPA records show no health-based violations for Elmhurst since 2016.

Nearby cities

All 192 cities in Illinois

Hardness data: TapWaterData US Water Hardness (utility report, September 3, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.