How hard is the water in Jefferson Davis County, MS?
0.9 grains per gallon
You do not need a softener here.
The median hardness measured in Jefferson Davis County, MS is 15 mg/L as calcium carbonate, which is 0.9 gpg. That is soft on the USGS scale. It comes from 11 samples at 2 sites between 2004 and 2013, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 0.6 and 1.2 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: low (how it is measured).
What to do next
You can skip the softener. At 0.9 gpg the most a softener would fix is the odd water spot. If a salesperson in Jefferson Davis County says otherwise, ask to see their reading in grains per gallon and compare it with this one.
More on when a softener is not worth it.
From 0.3 to 1.5 gpg
The softest single sample on record in Jefferson Davis County was 4.9 mg/L and the hardest 25.4 mg/L, a 5-fold gap. The top quarter of sites read above 1.2 gpg and the bottom quarter below 0.6 gpg.
Wells 0.3 gpg, rivers and lakes 1.5 gpg
1 groundwater samples from 1 wells put the median at 4.9 mg/L. 10 surface samples from 1 sites put it at 25.4 mg/L. In Jefferson Davis County the rivers and lakes come out 1.2 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.
Jefferson Davis County against the rest of Mississippi
Among the 78 Mississippi counties with data, Jefferson Davis County is number 57 of 78 counting from the hardest. Across the whole country it is harder than 5% of counties.
Softest in Mississippi: Issaquena County at 0.1 gpg. Hardest: Franklin County at 60.5 gpg. Closest to Jefferson Davis County: Prentiss County (0.9), Benton County (0.8), Lawrence County (0.8).