How hard is the water in Clinton County, IL?
11.6 grains per gallon
A softener will pay its way here.
The median hardness measured in Clinton County, IL is 199 mg/L as calcium carbonate, which is 11.6 gpg. That is very hard on the USGS scale. It comes from 335 samples at 16 sites between 1990 and 2003, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 10.4 and 15.1 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: high (how it is measured).
What to do next
At 11.6 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 Clinton 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 6.3 to 17.3 gpg
The softest single sample on record in Clinton County was 108 mg/L and the hardest 296 mg/L, a 3-fold gap. The top quarter of sites read above 15.1 gpg and the bottom quarter below 10.4 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 254 lb of salt a year (7 bags of 40 lb, about $46), 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 $146 a year.
Sizing at 11.6 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 696 | 24,000 | 85 lb |
| 2 | 1,392 | 24,000 | 169 lb |
| 4 | 2,784 | 24,000 | 339 lb |
| 6 | 4,176 | 32,000 | 508 lb |
Clinton County against the rest of Illinois
Among the 102 Illinois counties with data, Clinton County is number 88 of 102 counting from the hardest. Across the whole country it is harder than 57% of counties.
Softest in Illinois: Pope County at 4.3 gpg. Hardest: Cook County at 34.8 gpg. Closest to Clinton County: Williamson County (11.7), Washington County (11.7), Edwards County (11.4).