How hard is the water in Adams County, ID?

3.2 grains per gallon

You do not need a softener here.

The median hardness measured in Adams County, ID is 55 mg/L as calcium carbonate, which is 3.2 gpg. That is soft on the USGS scale. It comes from 87 samples at 18 sites between 1990 and 2011, 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 2.6 and 4.4 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

You can skip the softener. At 3.2 gpg the most a softener would fix is the odd water spot. If a salesperson in Adams County says otherwise, ask to see their reading in grains per gallon and compare it with this one. Because Adams County straddles a decision line, check your own tap with a $10 test strip before you spend anything.

More on when a softener is not worth it.

From 1.6 to 6.5 gpg

The softest single sample on record in Adams County was 26.9 mg/L and the hardest 112 mg/L, a 4-fold gap. The top quarter of sites read above 4.4 gpg and the bottom quarter below 2.6 gpg.

Adams County against the rest of Idaho

Among the 44 Idaho counties with data, Adams County is number 41 of 44 counting from the hardest. Across the whole country it is harder than 23% of counties.

Softest in Idaho: Valley County at 1.3 gpg. Hardest: Caribou County at 23 gpg. Closest to Adams County: Camas County (3.2), Shoshone County (4), Elmore County (4.4).