How hard is the water in Green Lake County, WI?
15 grains per gallon
A softener will pay its way here.
The median hardness measured in Green Lake County, WI is 257 mg/L as calcium carbonate, which is 15 gpg. That is very hard on the USGS scale. It comes from 105 samples at 18 sites between 1990 and 2023, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 12.9 and 19.3 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 15 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 9.3 to 27.0 gpg
The softest single sample on record in Green Lake County was 160 mg/L and the hardest 463 mg/L, a 3-fold gap. The top quarter of sites read above 19.3 gpg and the bottom quarter below 12.9 gpg.
Wells 25.1 gpg, rivers and lakes 13.3 gpg
5 groundwater samples from 3 wells put the median at 429 mg/L. 100 surface samples from 15 sites put it at 227 mg/L. In Green Lake County the wells come out 11.8 gpg harder. Groundwater sits in contact with rock for years and picks up calcium and magnesium as it goes, so wells usually read harder. A utility here that draws from the river can deliver noticeably different water from a private well next door.
What a softener would cost to run
For a household of 3, a 24,000-grain unit covers a week between regenerations. Expect about 328 lb of salt a year (9 bags of 40 lb, about $59), 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 $159 a year.
Sizing at 15 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 900 | 24,000 | 110 lb |
| 2 | 1,800 | 24,000 | 219 lb |
| 4 | 3,600 | 32,000 | 438 lb |
| 6 | 5,400 | 40,000 | 657 lb |
Green Lake County against the rest of Wisconsin
Among the 72 Wisconsin counties with data, Green Lake County is number 29 of 72 counting from the hardest. Across the whole country it is harder than 69% of counties.
Softest in Wisconsin: Vilas County at 1.4 gpg. Hardest: Calumet County at 28.4 gpg. Closest to Green Lake County: Shawano County (15), Richland County (14.9), Vernon County (15.2).