How hard is the water in Oldham County, KY?
13.2 grains per gallon
A softener will pay its way here.
The median hardness measured in Oldham County, KY is 227 mg/L as calcium carbonate, which is 13.2 gpg. That is very hard on the USGS scale. It comes from 49 samples at 3 sites between 1999 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 12.1 and 14.2 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
At 13.2 gpg a softener pays its way here. Before you buy, check the quoted unit's grain capacity against the sizing table below, and ask whether it regenerates on demand, which uses less salt than a timer. Call your utility for its own report if you are on city water.
More on sizing a softener for your household.
From 11.0 to 15.1 gpg
The softest single sample on record in Oldham County was 188 mg/L and the hardest 258.5 mg/L, a 1-fold gap. The top quarter of sites read above 14.2 gpg and the bottom quarter below 12.1 gpg.
Wells 11 gpg, rivers and lakes 14.2 gpg
1 groundwater samples from 1 wells put the median at 188 mg/L. 48 surface samples from 2 sites put it at 242.5 mg/L. In Oldham County the rivers and lakes come out 3.2 gpg harder. Here the surface water reads harder than the wells, which often points to streams fed by limestone springs or irrigation return flow. A utility here that draws from the aquifer 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 289 lb of salt a year (8 bags of 40 lb, about $52), 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 $152 a year.
Sizing at 13.2 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 792 | 24,000 | 96 lb |
| 2 | 1,584 | 24,000 | 193 lb |
| 4 | 3,168 | 24,000 | 385 lb |
| 6 | 4,752 | 40,000 | 578 lb |
Oldham County against the rest of Kentucky
Among the 104 Kentucky counties with data, Oldham County is number 10 of 104 counting from the hardest. Across the whole country it is harder than 63% of counties.
Softest in Kentucky: Letcher County at 0.3 gpg. Hardest: Jefferson County at 32.9 gpg. Closest to Oldham County: Trimble County (13.6), Union County (12.9), Robertson County (12.9).