How hard is the water in Decatur County, GA?
6.7 grains per gallon
Optional: a softener helps, but plenty of homes skip it.
The median hardness measured in Decatur County, GA is 114 mg/L as calcium carbonate, which is 6.7 gpg. That is moderately hard on the USGS scale. It comes from 100 samples at 29 sites between 1994 and 2026, drawn from groundwater wells, which is what most taps and private wells in the county draw on.
How much it varies here
Half the sites came in between 5.3 and 7.4 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 6.7 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 Decatur 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 0.0 to 9.1 gpg
The softest single sample on record in Decatur County was 0.2 mg/L and the hardest 156 mg/L, a 780-fold gap. The top quarter of sites read above 7.4 gpg and the bottom quarter below 5.3 gpg.
Wells 6.7 gpg, rivers and lakes 2 gpg
100 groundwater samples from 29 wells put the median at 114 mg/L. 1,127 surface samples from 25 sites put it at 34 mg/L. In Decatur County the wells come out 4.7 gpg harder. Groundwater sits in contact with rock for years and picks up calcium and magnesium as it goes, so wells usually read harder. A utility here that draws from the river can deliver noticeably different water from a private well next door.
What a softener would cost to run
For a household of 3, a 24,000-grain unit covers a week between regenerations. Expect about 145 lb of salt a year (4 bags of 40 lb, about $26), 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 $126 a year.
Sizing at 6.7 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 402 | 24,000 | 49 lb |
| 2 | 804 | 24,000 | 98 lb |
| 4 | 1,608 | 24,000 | 196 lb |
| 6 | 2,412 | 24,000 | 293 lb |
Decatur County against the rest of Georgia
Among the 159 Georgia counties with data, Decatur County is number 11 of 159 counting from the hardest. Across the whole country it is harder than 37% of counties.
Softest in Georgia: Richmond County at 0.2 gpg. Hardest: Glynn County at 13.6 gpg. Closest to Decatur County: Miller County (6.7), Polk County (6.8), McIntosh County (6.5).