How hard is the water in Daniels County, MT?
16 grains per gallon
A softener will pay its way here.
The median hardness measured in Daniels County, MT is 274 mg/L as calcium carbonate, which is 16 gpg. That is very hard on the USGS scale. It comes from 15 samples at 13 sites between 1990 and 2026, 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 14.6 and 23.8 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 16 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 9.7 to 37.9 gpg
The softest single sample on record in Daniels County was 166 mg/L and the hardest 648 mg/L, a 4-fold gap. The top quarter of sites read above 23.8 gpg and the bottom quarter below 14.6 gpg.
Wells 16 gpg, rivers and lakes 17.3 gpg
15 groundwater samples from 13 wells put the median at 273.5 mg/L. 160 surface samples from 16 sites put it at 295.3 mg/L. In Daniels County the rivers and lakes come out 1.3 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 349 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 16 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 960 | 24,000 | 117 lb |
| 2 | 1,920 | 24,000 | 234 lb |
| 4 | 3,840 | 32,000 | 467 lb |
| 6 | 5,760 | 48,000 | 701 lb |
Daniels County against the rest of Montana
Among the 56 Montana counties with data, Daniels County is number 28 of 56 counting from the hardest. Across the whole country it is harder than 72% of counties.
Softest in Montana: Lincoln County at 3.4 gpg. Hardest: Rosebud County at 138.9 gpg. Closest to Daniels County: Beaverhead County (15.7), Carbon County (15.7), Custer County (16.8).