How hard is the water in Redwood County, MN?
24.4 grains per gallon
A softener will pay its way here.
The median hardness measured in Redwood County, MN is 418 mg/L as calcium carbonate, which is 24.4 gpg. That is very hard on the USGS scale. It comes from 40 samples at 36 sites between 1991 and 2025, drawn from groundwater wells, which is what most taps and private wells in the county draw on.
How much it varies here
Half the sites came in between 19.9 and 54.5 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 24.4 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 1.3 to 132.6 gpg
The softest single sample on record in Redwood County was 21.5 mg/L and the hardest 2,270 mg/L, a 106-fold gap. The top quarter of sites read above 54.5 gpg and the bottom quarter below 19.9 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 24.4 gpg, rivers and lakes 29.6 gpg
40 groundwater samples from 36 wells put the median at 417.5 mg/L. 196 surface samples from 25 sites put it at 506 mg/L. In Redwood County the rivers and lakes come out 5.2 gpg harder. Here the surface water reads harder than the wells, which often points to streams fed by limestone springs or irrigation return flow. A utility here that draws from the aquifer can deliver noticeably different water from a private well next door.
What a softener would cost to run
For a household of 3, a 32,000-grain unit covers a week between regenerations. Expect about 533 lb of salt a year (14 bags of 40 lb, about $96), 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 $196 a year.
Sizing at 24.4 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,464 | 24,000 | 178 lb |
| 2 | 2,928 | 24,000 | 356 lb |
| 4 | 5,856 | 48,000 | 712 lb |
| 6 | 8,784 | 64,000 | 1,069 lb |
Redwood County against the rest of Minnesota
Among the 87 Minnesota counties with data, Redwood County is number 12 of 87 counting from the hardest. Across the whole country it is harder than 91% of counties.
Softest in Minnesota: Lake County at 1.3 gpg. Hardest: Traverse County at 42.6 gpg. Closest to Redwood County: Pipestone County (24.3), Nicollet County (25.1), Brown County (25.1).