How hard is the water in Dickinson County, IA?
20 grains per gallon
A softener will pay its way here.
The median hardness measured in Dickinson County, IA is 343 mg/L as calcium carbonate, which is 20 gpg. That is very hard on the USGS scale. It comes from 5 samples at 5 sites between 1990 and 2004, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 14.5 and 26.3 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 20 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 12.8 to 29.8 gpg
The softest single sample on record in Dickinson County was 219 mg/L and the hardest 510 mg/L, a 2-fold gap. The top quarter of sites read above 26.3 gpg and the bottom quarter below 14.5 gpg.
Wells 28 gpg, rivers and lakes 14.5 gpg
2 groundwater samples from 2 wells put the median at 480 mg/L. 3 surface samples from 3 sites put it at 248 mg/L. In Dickinson County the wells come out 13.5 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 32,000-grain unit covers a week between regenerations. Expect about 438 lb of salt a year (11 bags of 40 lb, about $79), 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 $179 a year.
Sizing at 20 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,200 | 24,000 | 146 lb |
| 2 | 2,400 | 24,000 | 292 lb |
| 4 | 4,800 | 40,000 | 584 lb |
| 6 | 7,200 | 64,000 | 876 lb |
Dickinson County against the rest of Iowa
Among the 93 Iowa counties with data, Dickinson County is number 44 of 93 counting from the hardest. Across the whole country it is harder than 84% of counties.
Softest in Iowa: Taylor County at 8.2 gpg. Hardest: Pocahontas County at 45.3 gpg. Closest to Dickinson County: Cedar County (19.9), Mahaska County (19.9), Tama County (19.9).