How hard is the water in Freeborn County, MN?
17.5 grains per gallon
A softener will pay its way here.
The median hardness measured in Freeborn County, MN is 299 mg/L as calcium carbonate, which is 17.5 gpg. That is very hard on the USGS scale. It comes from 86 samples at 17 sites between 1991 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 12.6 and 19.9 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 17.5 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 7.0 to 30.3 gpg
The softest single sample on record in Freeborn County was 120 mg/L and the hardest 518 mg/L, a 4-fold gap. The top quarter of sites read above 19.9 gpg and the bottom quarter below 12.6 gpg.
Wells 25.7 gpg, rivers and lakes 15.2 gpg
4 groundwater samples from 4 wells put the median at 440.5 mg/L. 82 surface samples from 13 sites put it at 261 mg/L. In Freeborn County the wells come out 10.5 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 381 lb of salt a year (10 bags of 40 lb, about $69), 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 $169 a year.
Sizing at 17.5 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,050 | 24,000 | 128 lb |
| 2 | 2,100 | 24,000 | 256 lb |
| 4 | 4,200 | 32,000 | 511 lb |
| 6 | 6,300 | 48,000 | 767 lb |
Freeborn County against the rest of Minnesota
Among the 87 Minnesota counties with data, Freeborn County is number 41 of 87 counting from the hardest. Across the whole country it is harder than 77% of counties.
Softest in Minnesota: Lake County at 1.3 gpg. Hardest: Traverse County at 42.6 gpg. Closest to Freeborn County: Kittson County (17.5), Fillmore County (17.3), Otter Tail County (17.6).