How hard is the water in Scott County, IA?
19.3 grains per gallon
A softener will pay its way here.
The median hardness measured in Scott County, IA is 330 mg/L as calcium carbonate, which is 19.3 gpg. That is very hard on the USGS scale. It comes from 32 samples at 9 sites between 1990 and 2007, 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 13.4 and 24.5 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 19.3 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.
More on sizing a softener for your household.
From 11.2 to 25.6 gpg
The softest single sample on record in Scott County was 191 mg/L and the hardest 438 mg/L, a 2-fold gap. The top quarter of sites read above 24.5 gpg and the bottom quarter below 13.4 gpg.
Wells 19.3 gpg, rivers and lakes 8.2 gpg
32 groundwater samples from 9 wells put the median at 330 mg/L. 27 surface samples from 8 sites put it at 140 mg/L. In Scott County the wells come out 11.1 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 421 lb of salt a year (11 bags of 40 lb, about $76), 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 $176 a year.
Sizing at 19.3 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,158 | 24,000 | 141 lb |
| 2 | 2,316 | 24,000 | 282 lb |
| 4 | 4,632 | 40,000 | 564 lb |
| 6 | 6,948 | 64,000 | 845 lb |
Scott County against the rest of Iowa
Among the 93 Iowa counties with data, Scott County is number 50 of 93 counting from the hardest. Across the whole country it is harder than 82% of counties.
Softest in Iowa: Taylor County at 8.2 gpg. Hardest: Pocahontas County at 45.3 gpg. Closest to Scott County: Cerro Gordo County (19.3), Fayette County (19.3), Johnson County (19.3).