How hard is the water in Alexander County, IL?
12 grains per gallon
A softener will pay its way here.
The median hardness measured in Alexander County, IL is 205 mg/L as calcium carbonate, which is 12 gpg. That is very hard on the USGS scale. It comes from 505 samples at 5 sites between 1990 and 2023, 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 12.4 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 12 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 Alexander 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 28.0 gpg
The softest single sample on record in Alexander County was 137.5 mg/L and the hardest 480 mg/L, a 3-fold gap. The top quarter of sites read above 12.4 gpg and the bottom quarter below 9.3 gpg.
Wells 28 gpg, rivers and lakes 10.7 gpg
1 groundwater samples from 1 wells put the median at 480 mg/L. 504 surface samples from 4 sites put it at 182.5 mg/L. In Alexander County the wells come out 17.3 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 262 lb of salt a year (7 bags of 40 lb, about $47), 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 $147 a year.
Sizing at 12 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 720 | 24,000 | 88 lb |
| 2 | 1,440 | 24,000 | 175 lb |
| 4 | 2,880 | 24,000 | 350 lb |
| 6 | 4,320 | 32,000 | 526 lb |
Alexander County against the rest of Illinois
Among the 102 Illinois counties with data, Alexander County is number 84 of 102 counting from the hardest. Across the whole country it is harder than 58% of counties.
Softest in Illinois: Pope County at 4.3 gpg. Hardest: Cook County at 34.8 gpg. Closest to Alexander County: Kankakee County (11.9), White County (11.9), Washington County (11.7).