Hard water in Beloit, WI
Reported by Beloit City of · September 2025
- WI typical
- 170 mg/L
- EPA health violations since 2016
- 2
- Softener for 3 people
- 32k grain
- Data
- Utility report
Beloit water measures 333 mg/L (19.5 gpg) of hardness, very hard by USGS standards. The number comes from Beloit City of, dated September 2025. Reports for this system disagree, with values from 154 to 333 mg/L.
At 333 mg/L, Beloit is 163 mg/L above the typical Wisconsin figure of 170. Of the 10 nearest cities we track, 8 have softer water and 2 have harder. The range nearby runs from 88 mg/L in Elkhorn to 360 in Delavan.
What 333 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 333 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 × 19.5 gpg = 4,381 grains a day. A 32,000-grain unit regenerates about every 7 days.
EPA record for Beloit's water system
2 health-based violations since 2016
Serves about 36,677 people from groundwater.
- Health-based
- 2
- Monitoring or reporting
- 1
- Open now
- 0
| Contaminant or rule | Violations | Period | Status |
|---|---|---|---|
| Combined radiumnaturally occurring radioactivity | 2 | 2019 | 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 Beloit water hard?
Yes. It measures about 333 mg/L (19.5 grains per gallon), which the USGS classes as very hard.
What is the water hardness in Beloit in grains per gallon?
About 19.5 gpg. One grain per gallon equals 17.1 mg/L, so 333 mg/L divided by 17.1 gives 19.5.
What size water softener do I need in Beloit?
For 3 people using 75 gallons each per day, 19.5 gpg works out to about 4,381 grains a day. A 32,000-grain softener covers that with a regeneration about every 7 days.
Has the Beloit water system had EPA violations?
EPA records show 2 health-based violations for Beloit City of since 2016, involving Combined radium. There were also 1 monitoring or reporting violation, which are about late or missing tests and notices.
Nearby cities
- Janesville298 mg/LVery hard
- Milton342 mg/LVery hard
- Delavan360 mg/LVery hard
- Edgerton291 mg/LVery hard
- Whitewater323 mg/LVery hard
- Elkhorn88 mg/LModerately hard
- Fort Atkinson278 mg/LVery hard
- Stoughton312 mg/LVery hard
- Monroe261 mg/LVery hard
- Oregon283 mg/LVery hard
Hardness data: TapWaterData US Water Hardness (utility report, September 26, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.