How hard is the water in Scott County, MN?
19.7 grains per gallon
A softener will pay its way here.
The median hardness measured in Scott County, MN is 337 mg/L as calcium carbonate, which is 19.7 gpg. That is very hard on the USGS scale. It comes from 22 samples at 10 sites between 1990 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 9.3 and 21.8 gpg. That spread crosses a decision line, so some homes here land on a different answer. A $10 test strip on your own tap settles it. Confidence in the county figure: medium (how it is measured).
What to do next
At 19.7 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. Because Scott County straddles a decision line, check your own tap with a $10 test strip before you spend anything.
More on sizing a softener for your household.
From 7.4 to 23.5 gpg
The softest single sample on record in Scott County was 126 mg/L and the hardest 403 mg/L, a 3-fold gap. The top quarter of sites read above 21.8 gpg and the bottom quarter below 9.3 gpg.
Wells 19.7 gpg, rivers and lakes 18.7 gpg
22 groundwater samples from 10 wells put the median at 336.5 mg/L. 178 surface samples from 34 sites put it at 319.8 mg/L. In Scott County the wells come out 1.0 gpg harder. Groundwater sits in contact with rock for years and picks up calcium and magnesium as it goes, so wells usually read harder. 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 32,000-grain unit covers a week between regenerations. Expect about 429 lb of salt a year (11 bags of 40 lb, about $77), 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 $177 a year.
Sizing at 19.7 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,182 | 24,000 | 144 lb |
| 2 | 2,364 | 24,000 | 288 lb |
| 4 | 4,728 | 40,000 | 575 lb |
| 6 | 7,092 | 64,000 | 863 lb |
Scott County against the rest of Minnesota
Among the 87 Minnesota counties with data, Scott County is number 30 of 87 counting from the hardest. Across the whole country it is harder than 83% of counties.
Softest in Minnesota: Lake County at 1.3 gpg. Hardest: Traverse County at 42.6 gpg. Closest to Scott County: Steele County (19.7), Stearns County (19.7), Murray County (19.6).