How hard is the water in Coal City, IL?
Reported by Coal City · May 2022
- IL typical
- 139 mg/L
- EPA health violations since 2016
- 7
- Softener for 3 people
- 24k grain
- Data
- Utility report
Tap water in Coal City has about 98 mg/L of hardness, which is 5.8 grains per gallon. On the USGS scale that counts as moderately hard. The number comes from Coal City, dated May 2022. Reports for this system disagree, with values from 57 to 98 mg/L.
Coal City sits 41 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 137 mg/L in New Lenox to 465 in Crest Hill.
What 98 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 × 5.8 gpg = 1,294 grains a day. A 24,000-grain unit regenerates about every 18 days.
EPA record for Coal City's water system
7 health-based violations since 2016
Serves about 5,845 people from groundwater.
- Health-based
- 7
- Monitoring or reporting
- 40
- Open now
- 2
| Contaminant or rule | Violations | Period | Status |
|---|---|---|---|
| Lead and Copper Rulecorrosion control and lead sampling | 1 | 2024 | Resolved |
| Combined radiumnaturally occurring radioactivity | 6 | 2019–2021 | Resolved |
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 Coal City water hard?
Somewhat. It measures about 98 mg/L (5.8 grains per gallon), which the USGS classes as moderately hard.
What is the water hardness in Coal City in grains per gallon?
About 5.8 gpg. One grain per gallon equals 17.1 mg/L, so 98 mg/L divided by 17.1 gives 5.8.
What size water softener do I need in Coal City?
For 3 people using 75 gallons each per day, 5.8 gpg works out to about 1,294 grains a day. A 24,000-grain softener covers that with a regeneration about every 18 days.
Has the Coal City water system had EPA violations?
EPA records show 7 health-based violations for Coal City since 2016, involving Lead and Copper Rule, Combined radium. There were also 40 monitoring or reporting violations, which are about late or missing tests and notices.
Nearby cities
- Channahon193 mg/LVery hard
- Morris285 mg/LVery hard
- Joliet244 mg/LVery hard
- Manhattan372 mg/LVery hard
- Bourbonnais138 mg/LHard
- Crest Hill465 mg/LVery hard
- New Lenox137 mg/LHard
- Manteno138 mg/LHard
- Bradley138 mg/LHard
- Kankakee140 mg/LHard
Hardness data: TapWaterData US Water Hardness (utility report, May 26, 2022), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.