How hard is the water in Tazewell County, IL?
19.9 grains per gallon
A softener will pay its way here.
The median hardness measured in Tazewell County, IL is 340 mg/L as calcium carbonate, which is 19.9 gpg. That is very hard on the USGS scale. It comes from 404 samples at 21 sites between 1990 and 2013, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 18.1 and 20.7 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: high (how it is measured).
What to do next
At 19.9 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.
More on sizing a softener for your household.
From 16.4 to 31.8 gpg
The softest single sample on record in Tazewell County was 280 mg/L and the hardest 544 mg/L, a 2-fold gap. The top quarter of sites read above 20.7 gpg and the bottom quarter below 18.1 gpg.
Wells 20.4 gpg, rivers and lakes 19.9 gpg
10 groundwater samples from 4 wells put the median at 350 mg/L. 394 surface samples from 17 sites put it at 340 mg/L. In Tazewell County the wells come out 0.5 gpg harder. Groundwater sits in contact with rock for years and picks up calcium and magnesium as it goes, so wells usually read harder. The two sources are close, so the county figure should hold whichever one your tap is on.
What a softener would cost to run
For a household of 3, a 32,000-grain unit covers a week between regenerations. Expect about 434 lb of salt a year (11 bags of 40 lb, about $78), 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 $178 a year.
Sizing at 19.9 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,194 | 24,000 | 145 lb |
| 2 | 2,388 | 24,000 | 291 lb |
| 4 | 4,776 | 40,000 | 581 lb |
| 6 | 7,164 | 64,000 | 872 lb |
Tazewell County against the rest of Illinois
Among the 102 Illinois counties with data, Tazewell County is number 31 of 102 counting from the hardest. Across the whole country it is harder than 84% of counties.
Softest in Illinois: Pope County at 4.3 gpg. Hardest: Cook County at 34.8 gpg. Closest to Tazewell County: Macon County (19.8), Wabash County (19.9), Peoria County (19.8).