How hard is the water in Carroll County, IA?
22.8 grains per gallon
A softener will pay its way here.
The median hardness measured in Carroll County, IA is 390 mg/L as calcium carbonate, which is 22.8 gpg. That is very hard on the USGS scale. It comes from 26 samples at 16 sites between 1990 and 2006, 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 19.9 and 25.1 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: medium (how it is measured).
What to do next
At 22.8 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 12.3 to 48.5 gpg
The softest single sample on record in Carroll County was 210 mg/L and the hardest 830 mg/L, a 4-fold gap. The top quarter of sites read above 25.1 gpg and the bottom quarter below 19.9 gpg.
What a softener would cost to run
For a household of 3, a 32,000-grain unit covers a week between regenerations. Expect about 498 lb of salt a year (13 bags of 40 lb, about $90), 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 $190 a year.
Sizing at 22.8 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,368 | 24,000 | 166 lb |
| 2 | 2,736 | 24,000 | 333 lb |
| 4 | 5,472 | 40,000 | 666 lb |
| 6 | 8,208 | 64,000 | 999 lb |
Carroll County against the rest of Iowa
Among the 93 Iowa counties with data, Carroll County is number 27 of 93 counting from the hardest. Across the whole country it is harder than 89% of counties.
Softest in Iowa: Taylor County at 8.2 gpg. Hardest: Pocahontas County at 45.3 gpg. Closest to Carroll County: Hamilton County (22.6), Pottawattamie County (22.9), Wapello County (22.5).