Hard water in Germantown, WI

Tap water hardness
422mg/L
24.7gpg
Very hard

Reported by Germantown Water Utility · August 2022

WI typical
170 mg/L
EPA health violations since 2016
1
Softener for 3 people
48k grain
Data
Utility report

The water in Germantown carries roughly 422 mg/L of dissolved calcium and magnesium, or 24.7 grains per gallon. That is very hard water. The number comes from Germantown Water Utility, dated August 2022.

Germantown on the hardness scale, with nearby cities
060120180240300360+WI typical 170Fox Point: 133 mg/LFox Point 133Menomonee Falls: 174 mg/LMenomonee Falls 174Lisbon: 332 mg/LLisbon 332Sussex: 332 mg/LSussex 332Jackson: 352 mg/LJackson 352Mequon: 440 mg/LMequon 440Cedarburg: 400 mg/LCedarburg 400Slinger: 485 mg/LSlinger 485Grafton: 370 mg/LGrafton 370Brookfield: 424 mg/LBrookfield 424Germantown 422off the scalemg/L as calcium carbonate060120180240300360+WI 170Menomonee Falls: 174 mg/LMenomonee. 174Lisbon: 332 mg/LLisbon 332Sussex: 332 mg/LSussex 332Jackson: 352 mg/LJackson 352Mequon: 440 mg/LMequon 440Cedarburg: 400 mg/LCedarburg 400422 mg/Loff the scalemg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

At 422 mg/L, Germantown is 252 mg/L above the typical Wisconsin figure of 170. Of the 10 nearest cities we track, 7 have softer water and 3 have harder. The range nearby runs from 133 mg/L in Fox Point to 485 in Slinger.

What 422 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 422 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 Germantown

3 people × 75 gallons a day × 24.7 gpg = 5,553 grains a day. A 48,000-grain unit regenerates about every 8 days.

Size it for your household

EPA record for Germantown's water system

Germantown Water Utility · PWSID WI2670105

1 health-based violation since 2016

Serves about 20,027 people from groundwater.

Health-based
1
Monitoring or reporting
22
Open now
1
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 Germantown water hard?

Yes. It measures about 422 mg/L (24.7 grains per gallon), which the USGS classes as very hard.

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

About 24.7 gpg. One grain per gallon equals 17.1 mg/L, so 422 mg/L divided by 17.1 gives 24.7.

What size water softener do I need in Germantown?

For 3 people using 75 gallons each per day, 24.7 gpg works out to about 5,553 grains a day. A 48,000-grain softener covers that with a regeneration about every 8 days.

Has the Germantown water system had EPA violations?

EPA records show 1 health-based violation for Germantown Water Utility since 2016, involving Lead and Copper Rule. There were also 22 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 15, 2022), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.