Hard water in Caledonia, WI

Tap water hardness
300mg/L
17.5gpg
Very hardCounty estimate

County estimate from 329 water samples in Racine County · July 2026

WI typical
170 mg/L
EPA health violations since 2016
1
Softener for 3 people
32k grain
Data
County estimate

Water samples from around Caledonia put hardness at about 300 mg/L (17.5 gpg), which would be very hard on the USGS scale. Treat this as a rough guide: it is the median of 329 samples taken across Racine County, mostly wells and streams, not a test of Caledonia's treated tap water. One more reason for caution: EPA lists Caledonia's water system as using surface water, which is often softer than the wells behind the county figure.

Caledonia on the hardness scale, with nearby cities
060120180240300360+WI typical 170St. Francis: 135 mg/LSt. Francis 135Greenfield: 135 mg/LGreenfield 135Racine: 136 mg/LRacine 136Mount Pleasant: 136 mg/LMount Pleasant 136Sturtevant: 136 mg/LSturtevant 136Cudahy: 142 mg/LCudahy 142Oak Creek: 210 mg/LOak Creek 210South Milwaukee: 210 mg/LSouth Milwaukee 210Franklin: 210 mg/LFranklin 210Union Grove: 313 mg/LUnion Grove 313Caledonia 300mg/L as calcium carbonate060120180240300360+WI 170Racine: 136 mg/LRacine 136Mount Pleasant: 136 mg/LMount Plea. 136Sturtevant: 136 mg/LSturtevant 136Oak Creek: 210 mg/LOak Creek 210South Milwaukee: 210 mg/LSouth Milw. 210Franklin: 210 mg/LFranklin 210300 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

Caledonia sits 130 mg/L above the typical Wisconsin figure of 170. Of the 10 nearest cities we track, 9 have softer water and 1 has harder. The range nearby runs from 135 mg/L in St. Francis to 313 in Union Grove.

What 300 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 300 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.

Softener size for Caledonia

3 people × 75 gallons a day × 17.5 gpg = 3,946 grains a day. A 32,000-grain unit regenerates about every 8 days.

Size it for your household

EPA record for Caledonia's water system

Caledonia Water Utility - Village of · PWSID WI2520184

1 health-based violation since 2016

Serves about 21,819 people from surface water.

Health-based
1
Monitoring or reporting
3
Open now
1

EPA lists this system as serving Caledonia.

20162017201820192020202120222023202420252026Lead and Copper Rule'16'18'20'22'24'26Lead and Copper Rule
Each dot is one health-based violation, placed at the start of its compliance period.
Contaminant or ruleViolationsPeriodStatus
Lead and Copper Rulecorrosion control and lead sampling12024Resolved

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 Caledonia water hard?

Yes. It measures about 300 mg/L (17.5 grains per gallon), which the USGS classes as very hard.

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

About 17.5 gpg. One grain per gallon equals 17.1 mg/L, so 300 mg/L divided by 17.1 gives 17.5.

What size water softener do I need in Caledonia?

For 3 people using 75 gallons each per day, 17.5 gpg works out to about 3,946 grains a day. A 32,000-grain softener covers that with a regeneration about every 8 days.

Has the Caledonia water system had EPA violations?

EPA records show 1 health-based violation for Caledonia Water Utility - Village of since 2016, involving Lead and Copper Rule. There were also 3 monitoring or reporting violations, which are about late or missing tests and notices.

Nearby cities

All 112 cities in Wisconsin

Hardness data: TapWaterData US Water Hardness (county estimate, July 4, 2026), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.