How hard is the water in Cumberland County, IL?
17.2 grains per gallon
A softener will pay its way here.
The median hardness measured in Cumberland County, IL is 294 mg/L as calcium carbonate, which is 17.2 gpg. That is very hard on the USGS scale. It comes from 108 samples at 7 sites between 1990 and 2004, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 14 and 17.7 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: medium (how it is measured).
What to do next
At 17.2 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 10.7 to 18.1 gpg
The softest single sample on record in Cumberland County was 183 mg/L and the hardest 310 mg/L, a 2-fold gap. The top quarter of sites read above 17.7 gpg and the bottom quarter below 14 gpg.
Wells 18.1 gpg, rivers and lakes 16 gpg
1 groundwater samples from 1 wells put the median at 310 mg/L. 107 surface samples from 6 sites put it at 274 mg/L. In Cumberland County the wells come out 2.1 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 24,000-grain unit covers a week between regenerations. Expect about 375 lb of salt a year (10 bags of 40 lb, about $68), 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 $168 a year.
Sizing at 17.2 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 1,032 | 24,000 | 126 lb |
| 2 | 2,064 | 24,000 | 251 lb |
| 4 | 4,128 | 32,000 | 502 lb |
| 6 | 6,192 | 48,000 | 753 lb |
Cumberland County against the rest of Illinois
Among the 102 Illinois counties with data, Cumberland County is number 53 of 102 counting from the hardest. Across the whole country it is harder than 76% of counties.
Softest in Illinois: Pope County at 4.3 gpg. Hardest: Cook County at 34.8 gpg. Closest to Cumberland County: Mercer County (17.3), Rock Island County (17.3), Clark County (16.9).