How hard is the water in Polk County, TX?
6.5 grains per gallon
Optional: a softener helps, but plenty of homes skip it.
The median hardness measured in Polk County, TX is 111 mg/L as calcium carbonate, which is 6.5 gpg. That is moderately hard on the USGS scale. It comes from 68 samples at 8 sites between 1994 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 5 and 8.4 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: medium (how it is measured).
What to do next
At 6.5 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 Polk 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 0.5 to 12.0 gpg
The softest single sample on record in Polk County was 7.8 mg/L and the hardest 206 mg/L, a 26-fold gap. The top quarter of sites read above 8.4 gpg and the bottom quarter below 5 gpg.
Wells 7.4 gpg, rivers and lakes 6.5 gpg
13 groundwater samples from 4 wells put the median at 126.5 mg/L. 55 surface samples from 4 sites put it at 110.5 mg/L. In Polk County the wells come out 0.9 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 141 lb of salt a year (4 bags of 40 lb, about $25), 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 $125 a year.
Sizing at 6.5 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 390 | 24,000 | 47 lb |
| 2 | 780 | 24,000 | 95 lb |
| 4 | 1,560 | 24,000 | 190 lb |
| 6 | 2,340 | 24,000 | 285 lb |
Polk County against the rest of Texas
Among the 217 Texas counties with data, Polk County is number 167 of 217 counting from the hardest. Across the whole country it is harder than 37% of counties.
Softest in Texas: Nacogdoches County at 0.3 gpg. Hardest: Ward County at 218.5 gpg. Closest to Polk County: Freestone County (6.6), Houston County (6.6), Rockwall County (6.3).