How hard is the water in Graves County, KY?

1.1 grains per gallon

You do not need a softener here.

The median hardness measured in Graves County, KY is 18 mg/L as calcium carbonate, which is 1.1 gpg. That is soft on the USGS scale. It comes from 129 samples at 6 sites between 2000 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 0.6 and 1.5 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 1.1 gpg the most a softener would fix is the odd water spot. If a salesperson in Graves 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 0.2 to 2.5 gpg

The softest single sample on record in Graves County was 3.7 mg/L and the hardest 42.7 mg/L, a 12-fold gap. The top quarter of sites read above 1.5 gpg and the bottom quarter below 0.6 gpg.

Wells 0.4 gpg, rivers and lakes 1.4 gpg

2 groundwater samples from 2 wells put the median at 6 mg/L. 127 surface samples from 4 sites put it at 24.3 mg/L. In Graves County the rivers and lakes come out 1.0 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.

Graves County against the rest of Kentucky

Among the 104 Kentucky counties with data, Graves County is number 103 of 104 counting from the hardest. Across the whole country it is harder than 7% of counties.

Softest in Kentucky: Letcher County at 0.3 gpg. Hardest: Jefferson County at 32.9 gpg. Closest to Graves County: Calloway County (1.2), Letcher County (0.3), Hickman County (1.8).