How hard is the water in Cape Girardeau County, MO?
16.4 grains per gallon
A softener will pay its way here.
The median hardness measured in Cape Girardeau County, MO is 282 mg/L as calcium carbonate, which is 16.4 gpg. That is very hard on the USGS scale. It comes from 36 samples at 13 sites between 1990 and 2016, drawn from groundwater wells, which is what most taps and private wells in the county draw on.
How much it varies here
Half the sites came in between 9.8 and 25.5 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: high (how it is measured).
What to do next
At 16.4 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 Cape Girardeau 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 2.3 to 45.2 gpg
The softest single sample on record in Cape Girardeau County was 39.4 mg/L and the hardest 774 mg/L, a 20-fold gap. The top quarter of sites read above 25.5 gpg and the bottom quarter below 9.8 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 16.4 gpg, rivers and lakes 8.2 gpg
36 groundwater samples from 13 wells put the median at 281.5 mg/L. 47 surface samples from 10 sites put it at 141 mg/L. In Cape Girardeau 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 24,000-grain unit covers a week between regenerations. Expect about 359 lb of salt a year (9 bags of 40 lb, about $65), 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 $165 a year.
Sizing at 16.4 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 984 | 24,000 | 120 lb |
| 2 | 1,968 | 24,000 | 239 lb |
| 4 | 3,936 | 32,000 | 479 lb |
| 6 | 5,904 | 48,000 | 718 lb |
Cape Girardeau County against the rest of Missouri
Among the 110 Missouri counties with data, Cape Girardeau County is number 13 of 110 counting from the hardest. Across the whole country it is harder than 74% of counties.
Softest in Missouri: Livingston County at 4.1 gpg. Hardest: Reynolds County at 96.7 gpg. Closest to Cape Girardeau County: Maries County (16.6), Macon County (16), Benton County (16.9).