How hard is the water in Clay County, IL?
10.9 grains per gallon
A softener will pay its way here.
The median hardness measured in Clay County, IL is 187 mg/L as calcium carbonate, which is 10.9 gpg. That is very hard on the USGS scale. It comes from 177 samples at 9 sites between 1990 and 2002, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 9.3 and 11.1 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: medium (how it is measured).
What to do next
At 10.9 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. Because Clay County straddles a decision line, check your own tap with a $10 test strip before you spend anything.
More on sizing a softener for your household.
From 8.0 to 16.2 gpg
The softest single sample on record in Clay County was 137 mg/L and the hardest 277 mg/L, a 2-fold gap. The top quarter of sites read above 11.1 gpg and the bottom quarter below 9.3 gpg.
What a softener would cost to run
For a household of 3, a 24,000-grain unit covers a week between regenerations. Expect about 239 lb of salt a year (6 bags of 40 lb, about $43), 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 $143 a year.
Sizing at 10.9 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 654 | 24,000 | 80 lb |
| 2 | 1,308 | 24,000 | 159 lb |
| 4 | 2,616 | 24,000 | 318 lb |
| 6 | 3,924 | 32,000 | 477 lb |
Clay County against the rest of Illinois
Among the 102 Illinois counties with data, Clay County is number 92 of 102 counting from the hardest. Across the whole country it is harder than 54% of counties.
Softest in Illinois: Pope County at 4.3 gpg. Hardest: Cook County at 34.8 gpg. Closest to Clay County: Jefferson County (10.9), Montgomery County (11), Jackson County (10.5).