How hard is the water in Goodhue County, MN?
13.9 grains per gallon
A softener will pay its way here.
The median hardness measured in Goodhue County, MN is 238 mg/L as calcium carbonate, which is 13.9 gpg. That is very hard on the USGS scale. It comes from 75 samples at 44 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 12.1 and 16.1 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 13.9 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 6.7 to 24.7 gpg
The softest single sample on record in Goodhue County was 115 mg/L and the hardest 423 mg/L, a 4-fold gap. The top quarter of sites read above 16.1 gpg and the bottom quarter below 12.1 gpg.
Wells 13.9 gpg, rivers and lakes 13.7 gpg
75 groundwater samples from 44 wells put the median at 237.5 mg/L. 145 surface samples from 24 sites put it at 235.3 mg/L. In Goodhue County the wells come out 0.2 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 24,000-grain unit covers a week between regenerations. Expect about 303 lb of salt a year (8 bags of 40 lb, about $55), 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 $155 a year.
Sizing at 13.9 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 834 | 24,000 | 101 lb |
| 2 | 1,668 | 24,000 | 203 lb |
| 4 | 3,336 | 24,000 | 406 lb |
| 6 | 5,004 | 40,000 | 609 lb |
Goodhue County against the rest of Minnesota
Among the 87 Minnesota counties with data, Goodhue County is number 60 of 87 counting from the hardest. Across the whole country it is harder than 66% of counties.
Softest in Minnesota: Lake County at 1.3 gpg. Hardest: Traverse County at 42.6 gpg. Closest to Goodhue County: Mille Lacs County (13.6), Renville County (13.6), Wadena County (13.5).