How hard is the water in Lauderdale County, TN?
9.9 grains per gallon
A softener is worth it here.
The median hardness measured in Lauderdale County, TN is 170 mg/L as calcium carbonate, which is 9.9 gpg. That is hard on the USGS scale. It comes from 277 samples at 37 sites between 1990 and 2017, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 5.9 and 15 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
At 9.9 gpg a softener is worth getting, mainly to protect the water heater and cut soap use. Get at least two quotes, ask each installer what grain capacity they are fitting, and check it against the sizing table below. Because Lauderdale County straddles a decision line, check your own tap with a $10 test strip before you spend anything.
More on sizing a softener for your household.
From 1.3 to 58.4 gpg
The softest single sample on record in Lauderdale County was 23 mg/L and the hardest 1,000 mg/L, a 43-fold gap. The top quarter of sites read above 15 gpg and the bottom quarter below 5.9 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 10.5 gpg, rivers and lakes 9.8 gpg
3 groundwater samples from 3 wells put the median at 179 mg/L. 274 surface samples from 34 sites put it at 168 mg/L. In Lauderdale County the wells come out 0.7 gpg harder. Groundwater sits in contact with rock for years and picks up calcium and magnesium as it goes, so wells usually read harder. 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 217 lb of salt a year (6 bags of 40 lb, about $39), 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 $139 a year.
Sizing at 9.9 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 594 | 24,000 | 72 lb |
| 2 | 1,188 | 24,000 | 145 lb |
| 4 | 2,376 | 24,000 | 289 lb |
| 6 | 3,564 | 32,000 | 434 lb |
Lauderdale County against the rest of Tennessee
Among the 95 Tennessee counties with data, Lauderdale County is number 21 of 95 counting from the hardest. Across the whole country it is harder than 51% of counties.
Softest in Tennessee: Fayette County at 0.5 gpg. Hardest: Fentress County at 42.9 gpg. Closest to Lauderdale County: Sevier County (9.6), Anderson County (9.5), McMinn County (9.3).