How hard is the water in Stephenson County, IL?
21.6 grains per gallon
A softener will pay its way here.
The median hardness measured in Stephenson County, IL is 370 mg/L as calcium carbonate, which is 21.6 gpg. That is very hard on the USGS scale. It comes from 195 samples at 13 sites between 1990 and 2002, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 20.6 and 22.6 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 21.6 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.
More on sizing a softener for your household.
From 19.9 to 29.8 gpg
The softest single sample on record in Stephenson County was 341 mg/L and the hardest 510 mg/L, a 1-fold gap. The top quarter of sites read above 22.6 gpg and the bottom quarter below 20.6 gpg.
Wells 29.8 gpg, rivers and lakes 21.6 gpg
4 groundwater samples from 1 wells put the median at 510 mg/L. 191 surface samples from 12 sites put it at 369 mg/L. In Stephenson County the wells come out 8.2 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 32,000-grain unit covers a week between regenerations. Expect about 472 lb of salt a year (12 bags of 40 lb, about $85), 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 $185 a year.
Sizing at 21.6 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,296 | 24,000 | 158 lb |
| 2 | 2,592 | 24,000 | 315 lb |
| 4 | 5,184 | 40,000 | 631 lb |
| 6 | 7,776 | 64,000 | 946 lb |
Stephenson County against the rest of Illinois
Among the 102 Illinois counties with data, Stephenson County is number 19 of 102 counting from the hardest. Across the whole country it is harder than 87% of counties.
Softest in Illinois: Pope County at 4.3 gpg. Hardest: Cook County at 34.8 gpg. Closest to Stephenson County: Logan County (21.7), Kendall County (21.8), Stark County (21.9).