How hard is the water in Washington County, IL?
11.7 grains per gallon
A softener will pay its way here.
The median hardness measured in Washington County, IL is 201 mg/L as calcium carbonate, which is 11.7 gpg. That is very hard on the USGS scale. It comes from 159 samples at 14 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 9.5 and 16.3 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 11.7 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 Washington 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 5.8 to 58.4 gpg
The softest single sample on record in Washington County was 99 mg/L and the hardest 1,000 mg/L, a 10-fold gap. The top quarter of sites read above 16.3 gpg and the bottom quarter below 9.5 gpg.
Wells 58.4 gpg, rivers and lakes 10.7 gpg
1 groundwater samples from 1 wells put the median at 1000 mg/L. 157 surface samples from 12 sites put it at 184 mg/L. In Washington County the wells come out 47.7 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 24,000-grain unit covers a week between regenerations. Expect about 256 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 11.7 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 702 | 24,000 | 85 lb |
| 2 | 1,404 | 24,000 | 171 lb |
| 4 | 2,808 | 24,000 | 342 lb |
| 6 | 4,212 | 32,000 | 512 lb |
Washington County against the rest of Illinois
Among the 102 Illinois counties with data, Washington County is number 86 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 Washington County: Williamson County (11.7), Clinton County (11.6), White County (11.9).