How hard is the water in Cumberland County, TN?

1.9 grains per gallon

You do not need a softener here.

The median hardness measured in Cumberland County, TN is 33 mg/L as calcium carbonate, which is 1.9 gpg. That is soft on the USGS scale. It comes from 650 samples at 48 sites between 1990 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 1.3 and 4.5 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

You can skip the softener. At 1.9 gpg the most a softener would fix is the odd water spot. If a salesperson in Cumberland County says otherwise, ask to see their reading in grains per gallon and compare it with this one. Because Cumberland County straddles a decision line, check your own tap with a $10 test strip before you spend anything.

More on when a softener is not worth it.

From 0.2 to 15.1 gpg

The softest single sample on record in Cumberland County was 4 mg/L and the hardest 258 mg/L, a 65-fold gap. The top quarter of sites read above 4.5 gpg and the bottom quarter below 1.3 gpg. So even in a soft county, a handful of wells here produce water hard enough to scale a heater.

Cumberland County against the rest of Tennessee

Among the 95 Tennessee counties with data, Cumberland County is number 82 of 95 counting from the hardest. Across the whole country it is harder than 15% of counties.

Softest in Tennessee: Fayette County at 0.5 gpg. Hardest: Fentress County at 42.9 gpg. Closest to Cumberland County: Lewis County (1.9), Hardin County (1.8), Henry County (1.8).