How hard is the water in Rankin County, MS?

1.5 grains per gallon

You do not need a softener here.

The median hardness measured in Rankin County, MS is 25 mg/L as calcium carbonate, which is 1.5 gpg. That is soft on the USGS scale. It comes from 12 samples at 7 sites between 1992 and 2018, drawn from every sampling site in the county, wells and surface water together.

How much it varies here

Half the sites came in between 0.3 and 2.2 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: medium (how it is measured).

What to do next

You can skip the softener. At 1.5 gpg the most a softener would fix is the odd water spot. If a salesperson in Rankin 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 0.0 to 12.2 gpg

The softest single sample on record in Rankin County was 0.7 mg/L and the hardest 208 mg/L, a 297-fold gap. The top quarter of sites read above 2.2 gpg and the bottom quarter below 0.3 gpg. So even in a soft county, a handful of wells here produce water hard enough to scale a heater.

Wells 0 gpg, rivers and lakes 1.7 gpg

3 groundwater samples from 3 wells put the median at 0.8 mg/L. 9 surface samples from 4 sites put it at 29.1 mg/L. In Rankin County the rivers and lakes come out 1.7 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.

Rankin County against the rest of Mississippi

Among the 78 Mississippi counties with data, Rankin County is number 39 of 78 counting from the hardest. Across the whole country it is harder than 12% of counties.

Softest in Mississippi: Issaquena County at 0.1 gpg. Hardest: Franklin County at 60.5 gpg. Closest to Rankin County: DeSoto County (1.4), Marion County (1.4), Tallahatchie County (1.3).