How hard is the water in Mississippi County, MO?
9.2 grains per gallon
A softener is worth it here.
The median hardness measured in Mississippi County, MO is 158 mg/L as calcium carbonate, which is 9.2 gpg. That is hard on the USGS scale. It comes from 72 samples at 9 sites between 1996 and 2019, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 8.6 and 9.7 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 9.2 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.
More on sizing a softener for your household.
From 6.5 to 20.4 gpg
The softest single sample on record in Mississippi County was 112 mg/L and the hardest 349 mg/L, a 3-fold gap. The top quarter of sites read above 9.7 gpg and the bottom quarter below 8.6 gpg.
Wells 8.8 gpg, rivers and lakes 9.3 gpg
3 groundwater samples from 3 wells put the median at 151 mg/L. 69 surface samples from 6 sites put it at 159.5 mg/L. In Mississippi County the rivers and lakes come out 0.5 gpg harder. Here the surface water reads harder than the wells, which often points to streams fed by limestone springs or irrigation return flow. 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 202 lb of salt a year (6 bags of 40 lb, about $36), 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 $136 a year.
Sizing at 9.2 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 552 | 24,000 | 67 lb |
| 2 | 1,104 | 24,000 | 134 lb |
| 4 | 2,208 | 24,000 | 269 lb |
| 6 | 3,312 | 24,000 | 403 lb |
Mississippi County against the rest of Missouri
Among the 110 Missouri counties with data, Mississippi County is number 97 of 110 counting from the hardest. Across the whole country it is harder than 48% of counties.
Softest in Missouri: Livingston County at 4.1 gpg. Hardest: Reynolds County at 96.7 gpg. Closest to Mississippi County: McDonald County (9.1), Barry County (9.4), Stoddard County (9).