How hard is the water in Karnes County, TX?
10.7 grains per gallon
A softener will pay its way here.
The median hardness measured in Karnes County, TX is 183 mg/L as calcium carbonate, which is 10.7 gpg. That is very hard on the USGS scale. It comes from 11 samples at 8 sites between 1990 and 2016, 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 7.8 and 26.9 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 10.7 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. Because Karnes 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 0.5 to 30.8 gpg
The softest single sample on record in Karnes County was 8.7 mg/L and the hardest 527 mg/L, a 61-fold gap. The top quarter of sites read above 26.9 gpg and the bottom quarter below 7.8 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 10.7 gpg, rivers and lakes 18.4 gpg
11 groundwater samples from 8 wells put the median at 182.5 mg/L. 80 surface samples from 4 sites put it at 315.5 mg/L. In Karnes County the rivers and lakes come out 7.7 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 233 lb of salt a year (6 bags of 40 lb, about $42), 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 $142 a year.
Sizing at 10.7 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 642 | 24,000 | 78 lb |
| 2 | 1,284 | 24,000 | 156 lb |
| 4 | 2,568 | 24,000 | 312 lb |
| 6 | 3,852 | 32,000 | 469 lb |
Karnes County against the rest of Texas
Among the 217 Texas counties with data, Karnes County is number 131 of 217 counting from the hardest. Across the whole country it is harder than 53% of counties.
Softest in Texas: Nacogdoches County at 0.3 gpg. Hardest: Ward County at 218.5 gpg. Closest to Karnes County: Atascosa County (10.6), Bastrop County (10.5), Bailey County (10.9).