Hard water in Delavan, WI

Tap water hardness
360mg/L
21.1gpg
Very hard

Reported by Delavan Waterworks · August 2022

WI typical
170 mg/L
EPA health violations since 2016
0
Softener for 3 people
48k grain
Data
Utility report

Delavan water measures 360 mg/L (21.1 gpg) of hardness, very hard by USGS standards. The number comes from Delavan Waterworks, dated August 2022.

Delavan on the hardness scale, with nearby cities
060120180240300360+WI typical 170Elkhorn: 88 mg/LElkhorn 88Burlington: 248 mg/LBurlington 248Fort Atkinson: 278 mg/LFort Atkinson 278Jefferson: 280 mg/LJefferson 280Edgerton: 291 mg/LEdgerton 291Janesville: 298 mg/LJanesville 298Union Grove: 313 mg/LUnion Grove 313Whitewater: 323 mg/LWhitewater 323Beloit: 333 mg/LBeloit 333Milton: 342 mg/LMilton 342Delavan 360mg/L as calcium carbonate060120180240300360+WI 170Elkhorn: 88 mg/LElkhorn 88Burlington: 248 mg/LBurlington 248Janesville: 298 mg/LJanesville 298Whitewater: 323 mg/LWhitewater 323Beloit: 333 mg/LBeloit 333Milton: 342 mg/LMilton 342360 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

Delavan sits 190 mg/L above the typical Wisconsin figure of 170. None of the 10 nearest cities we track has harder water. The range nearby runs from 88 mg/L in Elkhorn to 342 in Milton.

What 360 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 360 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 Delavan

3 people × 75 gallons a day × 21.1 gpg = 4,736 grains a day. A 48,000-grain unit regenerates about every 10 days.

Size it for your household

EPA record for Delavan's water system

Delavan Waterworks · PWSID WI2650113

No health-based violations since 2016

Serves about 9,028 people from groundwater.

Health-based
0
Monitoring or reporting
2
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 Delavan water hard?

Yes. It measures about 360 mg/L (21.1 grains per gallon), which the USGS classes as very hard.

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

About 21.1 gpg. One grain per gallon equals 17.1 mg/L, so 360 mg/L divided by 17.1 gives 21.1.

What size water softener do I need in Delavan?

For 3 people using 75 gallons each per day, 21.1 gpg works out to about 4,736 grains a day. A 48,000-grain softener covers that with a regeneration about every 10 days.

Has the Delavan water system had EPA violations?

EPA records show no health-based violations for Delavan Waterworks since 2016. There were also 2 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 (utility report, August 16, 2022), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.