How hard is the water in Grayson County, TX?
7.8 grains per gallon
A softener is worth it here.
The median hardness measured in Grayson County, TX is 134 mg/L as calcium carbonate, which is 7.8 gpg. That is hard on the USGS scale. It comes from 394 samples at 10 sites between 1990 and 2023, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 1.9 and 16.1 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 7.8 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 Grayson 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 0.3 to 30.6 gpg
The softest single sample on record in Grayson County was 4.6 mg/L and the hardest 523 mg/L, a 114-fold gap. The top quarter of sites read above 16.1 gpg and the bottom quarter below 1.9 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 0.3 gpg, rivers and lakes 11.2 gpg
3 groundwater samples from 3 wells put the median at 5.5 mg/L. 391 surface samples from 7 sites put it at 191 mg/L. In Grayson County the rivers and lakes come out 10.9 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 170 lb of salt a year (5 bags of 40 lb, about $31), 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 $131 a year.
Sizing at 7.8 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 468 | 24,000 | 57 lb |
| 2 | 936 | 24,000 | 114 lb |
| 4 | 1,872 | 24,000 | 228 lb |
| 6 | 2,808 | 24,000 | 342 lb |
Grayson County against the rest of Texas
Among the 217 Texas counties with data, Grayson County is number 155 of 217 counting from the hardest. Across the whole country it is harder than 42% of counties.
Softest in Texas: Nacogdoches County at 0.3 gpg. Hardest: Ward County at 218.5 gpg. Closest to Grayson County: Kaufman County (7.8), Collin County (7.9), Lamar County (7.9).