How hard is the water in Iowa County, WI?

23.4 grains per gallon

A softener will pay its way here.

The median hardness measured in Iowa County, WI is 400 mg/L as calcium carbonate, which is 23.4 gpg. That is very hard on the USGS scale. It comes from 116 samples at 12 sites between 1990 and 2000, drawn from every sampling site in the county, wells and surface water together.

How much it varies here

Half the sites came in between 23 and 24 gpg. The whole middle of that range gives the same answer, so a test of your own tap is unlikely to change it. Confidence in the county figure: high (how it is measured).

What to do next

At 23.4 gpg a softener pays its way here. Before you buy, check the quoted unit's grain capacity against the sizing table below, and ask whether it regenerates on demand, which uses less salt than a timer. Call your utility for its own report if you are on city water.

More on sizing a softener for your household.

From 22.2 to 24.2 gpg

The softest single sample on record in Iowa County was 380 mg/L and the hardest 415 mg/L, a 1-fold gap. The top quarter of sites read above 24 gpg and the bottom quarter below 23 gpg.

What a softener would cost to run

For a household of 3, a 32,000-grain unit covers a week between regenerations. Expect about 510 lb of salt a year (13 bags of 40 lb, about $92), and roughly 2,346 gallons of regeneration water. Installed, most units run $1,000 to $4,500; spread over 15 years with salt, that is about $192 a year.

Sizing at 23.4 gpg

Iowa County against the rest of Wisconsin

Among the 72 Wisconsin counties with data, Iowa County is number 5 of 72 counting from the hardest. Across the whole country it is harder than 90% of counties.

Softest in Wisconsin: Vilas County at 1.4 gpg. Hardest: Calumet County at 28.4 gpg. Closest to Iowa County: Waukesha County (23.4), Washington County (22.1), Ozaukee County (21.6).