How hard is the water in Red Lake County, MN?
15.9 grains per gallon
A softener will pay its way here.
The median hardness measured in Red Lake County, MN is 273 mg/L as calcium carbonate, which is 15.9 gpg. That is very hard on the USGS scale. It comes from 14 samples at 13 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 12.3 and 18.9 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: medium (how it is measured).
What to do next
At 15.9 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 3.9 to 45.1 gpg
The softest single sample on record in Red Lake County was 66.9 mg/L and the hardest 772 mg/L, a 12-fold gap. The top quarter of sites read above 18.9 gpg and the bottom quarter below 12.3 gpg.
Wells 15.9 gpg, rivers and lakes 17.8 gpg
14 groundwater samples from 13 wells put the median at 273 mg/L. 54 surface samples from 12 sites put it at 305.5 mg/L. In Red Lake County the rivers and lakes come out 1.9 gpg harder. Here the surface water reads harder than the wells, which often points to streams fed by limestone springs or irrigation return flow. The two sources are close, so the county figure should hold whichever one your tap is on.
What a softener would cost to run
For a household of 3, a 24,000-grain unit covers a week between regenerations. Expect about 348 lb of salt a year (9 bags of 40 lb, about $63), 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 $163 a year.
Sizing at 15.9 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 954 | 24,000 | 116 lb |
| 2 | 1,908 | 24,000 | 232 lb |
| 4 | 3,816 | 32,000 | 464 lb |
| 6 | 5,724 | 48,000 | 696 lb |
Red Lake County against the rest of Minnesota
Among the 87 Minnesota counties with data, Red Lake County is number 51 of 87 counting from the hardest. Across the whole country it is harder than 72% of counties.
Softest in Minnesota: Lake County at 1.3 gpg. Hardest: Traverse County at 42.6 gpg. Closest to Red Lake County: Marshall County (15.9), Mower County (15.9), Sherburne County (15.9).