How hard is the water in Stone County, MO?
9.5 grains per gallon
A softener is worth it here.
The median hardness measured in Stone County, MO is 162 mg/L as calcium carbonate, which is 9.5 gpg. That is hard on the USGS scale. It comes from 177 samples at 14 sites between 1990 and 2023, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 7 and 10.7 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 9.5 gpg a softener is worth getting, mainly to protect the water heater and cut soap use. Get at least two quotes, ask each installer what grain capacity they are fitting, and check it against the sizing table below. Because Stone 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 5.4 to 11.4 gpg
The softest single sample on record in Stone County was 91.7 mg/L and the hardest 195 mg/L, a 2-fold gap. The top quarter of sites read above 10.7 gpg and the bottom quarter below 7 gpg.
Wells 11.3 gpg, rivers and lakes 9.4 gpg
3 groundwater samples from 3 wells put the median at 194 mg/L. 174 surface samples from 11 sites put it at 161.5 mg/L. In Stone County the wells come out 1.9 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 206 lb of salt a year (6 bags of 40 lb, about $37), 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 $137 a year.
Sizing at 9.5 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 570 | 24,000 | 69 lb |
| 2 | 1,140 | 24,000 | 139 lb |
| 4 | 2,280 | 24,000 | 277 lb |
| 6 | 3,420 | 24,000 | 416 lb |
Stone County against the rest of Missouri
Among the 110 Missouri counties with data, Stone County is number 94 of 110 counting from the hardest. Across the whole country it is harder than 49% of counties.
Softest in Missouri: Livingston County at 4.1 gpg. Hardest: Reynolds County at 96.7 gpg. Closest to Stone County: Newton County (9.4), Barry County (9.4), Ste. Genevieve County (9.6).