How hard is the water in Jo Daviess County, IL?
20.7 grains per gallon
A softener will pay its way here.
The median hardness measured in Jo Daviess County, IL is 354 mg/L as calcium carbonate, which is 20.7 gpg. That is very hard on the USGS scale. It comes from 214 samples at 19 sites between 1990 and 2017, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 20.2 and 23.2 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 20.7 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.
More on sizing a softener for your household.
From 10.9 to 27.5 gpg
The softest single sample on record in Jo Daviess County was 187 mg/L and the hardest 470 mg/L, a 3-fold gap. The top quarter of sites read above 23.2 gpg and the bottom quarter below 20.2 gpg.
Wells 15.5 gpg, rivers and lakes 20.7 gpg
3 groundwater samples from 1 wells put the median at 265 mg/L. 211 surface samples from 18 sites put it at 354.3 mg/L. In Jo Daviess County the rivers and lakes come out 5.2 gpg harder. Here the surface water reads harder than the wells, which often points to streams fed by limestone springs or irrigation return flow. A utility here that draws from the aquifer can deliver noticeably different water from a private well next door.
What a softener would cost to run
For a household of 3, a 32,000-grain unit covers a week between regenerations. Expect about 451 lb of salt a year (12 bags of 40 lb, about $81), 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 $181 a year.
Sizing at 20.7 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,242 | 24,000 | 151 lb |
| 2 | 2,484 | 24,000 | 302 lb |
| 4 | 4,968 | 40,000 | 604 lb |
| 6 | 7,452 | 64,000 | 907 lb |
Jo Daviess County against the rest of Illinois
Among the 102 Illinois counties with data, Jo Daviess County is number 24 of 102 counting from the hardest. Across the whole country it is harder than 85% of counties.
Softest in Illinois: Pope County at 4.3 gpg. Hardest: Cook County at 34.8 gpg. Closest to Jo Daviess County: McDonough County (20.6), Boone County (20.7), Fulton County (20.6).