HardnessCheck

How hard is the water in Mercer County, WV?

5.5 grains per gallon

Optional: a softener helps, but plenty of homes skip it.

The median hardness measured in Mercer County, WV is 94 mg/L as calcium carbonate, which is 5.5 gpg. That is moderately hard on the USGS scale. It comes from 35 samples at 6 sites between 1996 and 2016, drawn from every sampling site in the county, wells and surface water together.

How much it varies here

Half the sites came in between 2.4 and 5.6 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: medium (how it is measured).

What to do next

At 5.5 gpg this is your call. Look for white film on glasses and crust on the shower head: if you see little of either, you can live without one. If you do want one, a 24,000-grain unit is enough, so ask for that size rather than a bigger one. Because Mercer 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 10.6 gpg

The softest single sample on record in Mercer County was 3.3 mg/L and the hardest 181 mg/L, a 55-fold gap. The top quarter of sites read above 5.6 gpg and the bottom quarter below 2.4 gpg.

Wells 5.5 gpg, rivers and lakes 5.5 gpg

3 groundwater samples from 3 wells put the median at 93.6 mg/L. 32 surface samples from 3 sites put it at 94.1 mg/L. In Mercer County the rivers and lakes come out 0.0 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.

What a softener would cost to run

For a household of 3, a 24,000-grain unit covers a week between regenerations. Expect about 120 lb of salt a year (3 bags of 40 lb, about $22), 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 $122 a year.

Sizing at 5.5 gpg

PeopleGrains a dayUnitSalt a year
133024,00040 lb
266024,00080 lb
41,32024,000161 lb
61,98024,000241 lb

Mercer County against the rest of West Virginia

Among the 54 West Virginia counties with data, Mercer County is number 36 of 54 counting from the hardest. Across the whole country it is harder than 33% of counties.

Softest in West Virginia: Calhoun County at 0.3 gpg. Hardest: Jefferson County at 20.4 gpg. Closest to Mercer County: Hardy County (5.5), Summers County (5.5), Logan County (5.4).