How hard is the water in Waukegan, IL?
Reported by Waukegan · April 2025
- IL typical
- 139 mg/L
- EPA health violations since 2016
- 0
- Softener for 3 people
- 24k grain
- Data
- Utility report
The water in Waukegan carries roughly 119 mg/L of dissolved calcium and magnesium, or 7.0 grains per gallon. That is moderately hard water. The number comes from Waukegan, dated April 2025. Reports for this system disagree, with values from 119 to 140 mg/L.
At 119 mg/L, Waukegan is 20 mg/L below the typical Illinois figure of 139. None of the 10 nearest cities we track has softer water. The range nearby runs from 120 mg/L in Highwood to 250 in Gurnee.
What 119 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.
3 people × 75 gallons a day × 7.0 gpg = 1,566 grains a day. A 24,000-grain unit regenerates about every 15 days.
EPA record for Waukegan's water system
No health-based violations since 2016
Serves about 87,149 people from surface water.
- Health-based
- 0
- Monitoring or reporting
- 7
- Open now
- 1
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 Waukegan water hard?
Somewhat. It measures about 119 mg/L (7.0 grains per gallon), which the USGS classes as moderately hard.
What is the water hardness in Waukegan in grains per gallon?
About 7.0 gpg. One grain per gallon equals 17.1 mg/L, so 119 mg/L divided by 17.1 gives 7.0.
What size water softener do I need in Waukegan?
For 3 people using 75 gallons each per day, 7.0 gpg works out to about 1,566 grains a day. A 24,000-grain softener covers that with a regeneration about every 15 days.
Has the Waukegan water system had EPA violations?
EPA records show no health-based violations for Waukegan since 2016. There were also 7 monitoring or reporting violations, which are about late or missing tests and notices.
Nearby cities
- Gurnee250 mg/LVery hard
- North Chicago136 mg/LHard
- Lake Bluff128 mg/LHard
- Zion250 mg/LVery hard
- Libertyville250 mg/LVery hard
- Grayslake250 mg/LVery hard
- Mundelein250 mg/LVery hard
- Vernon Hills250 mg/LVery hard
- Lake Villa205 mg/LVery hard
- Highwood120 mg/LModerately hard
Hardness data: TapWaterData US Water Hardness (utility report, April 21, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.