How hard is the water in Garfield County, MT?
12.3 grains per gallon
A softener will pay its way here.
The median hardness measured in Garfield County, MT is 211 mg/L as calcium carbonate, which is 12.3 gpg. That is very hard on the USGS scale. It comes from 83 samples at 28 sites between 1992 and 2026, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 8.2 and 17.2 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: high (how it is measured).
What to do next
At 12.3 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 Garfield 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 2.0 to 102.8 gpg
The softest single sample on record in Garfield County was 35 mg/L and the hardest 1,760 mg/L, a 50-fold gap. The top quarter of sites read above 17.2 gpg and the bottom quarter below 8.2 gpg. So even here some sites draw water soft enough to need nothing at all.
What a softener would cost to run
For a household of 3, a 24,000-grain unit covers a week between regenerations. Expect about 269 lb of salt a year (7 bags of 40 lb, about $48), 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 $148 a year.
Sizing at 12.3 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 738 | 24,000 | 90 lb |
| 2 | 1,476 | 24,000 | 180 lb |
| 4 | 2,952 | 24,000 | 359 lb |
| 6 | 4,428 | 32,000 | 539 lb |
Garfield County against the rest of Montana
Among the 56 Montana counties with data, Garfield County is number 37 of 56 counting from the hardest. Across the whole country it is harder than 60% of counties.
Softest in Montana: Lincoln County at 3.4 gpg. Hardest: Rosebud County at 138.9 gpg. Closest to Garfield County: Silver Bow County (12.6), Chouteau County (11.4), Gallatin County (11.4).