How hard is the water in Cassia County, ID?
14.4 grains per gallon
A softener will pay its way here.
The median hardness measured in Cassia County, ID is 247 mg/L as calcium carbonate, which is 14.4 gpg. That is very hard on the USGS scale. It comes from 304 samples at 86 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 11.8 and 17.6 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 14.4 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 0.9 to 76.5 gpg
The softest single sample on record in Cassia County was 15 mg/L and the hardest 1,310 mg/L, an 87-fold gap. The top quarter of sites read above 17.6 gpg and the bottom quarter below 11.8 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 14.4 gpg, rivers and lakes 5.4 gpg
304 groundwater samples from 86 wells put the median at 246.5 mg/L. 17 surface samples from 4 sites put it at 93.2 mg/L. In Cassia County the wells come out 9.0 gpg harder. Groundwater sits in contact with rock for years and picks up calcium and magnesium as it goes, so wells usually read harder. A utility here that draws from the river can deliver noticeably different water from a private well next door.
What a softener would cost to run
For a household of 3, a 24,000-grain unit covers a week between regenerations. Expect about 314 lb of salt a year (8 bags of 40 lb, about $57), 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 $157 a year.
Sizing at 14.4 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 864 | 24,000 | 105 lb |
| 2 | 1,728 | 24,000 | 210 lb |
| 4 | 3,456 | 32,000 | 420 lb |
| 6 | 5,184 | 40,000 | 631 lb |
Cassia County against the rest of Idaho
Among the 44 Idaho counties with data, Cassia County is number 8 of 44 counting from the hardest. Across the whole country it is harder than 68% of counties.
Softest in Idaho: Valley County at 1.3 gpg. Hardest: Caribou County at 23 gpg. Closest to Cassia County: Power County (13.8), Jerome County (13.6), Bonneville County (13.4).