How hard is the water in Dallas County, TX?
8.3 grains per gallon
A softener is worth it here.
The median hardness measured in Dallas County, TX is 142 mg/L as calcium carbonate, which is 8.3 gpg. That is hard on the USGS scale. It comes from 1,725 samples at 40 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 6.8 and 9.8 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 8.3 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 Dallas 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 0.7 to 16.1 gpg
The softest single sample on record in Dallas County was 11.4 mg/L and the hardest 275 mg/L, a 24-fold gap. The top quarter of sites read above 9.8 gpg and the bottom quarter below 6.8 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 0.7 gpg, rivers and lakes 9.2 gpg
1 groundwater samples from 1 wells put the median at 11.4 mg/L. 1,691 surface samples from 34 sites put it at 156.8 mg/L. In Dallas County the rivers and lakes come out 8.5 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 182 lb of salt a year (5 bags of 40 lb, about $33), 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 $133 a year.
Sizing at 8.3 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 498 | 24,000 | 61 lb |
| 2 | 996 | 24,000 | 121 lb |
| 4 | 1,992 | 24,000 | 242 lb |
| 6 | 2,988 | 24,000 | 364 lb |
Dallas County against the rest of Texas
Among the 217 Texas counties with data, Dallas County is number 149 of 217 counting from the hardest. Across the whole country it is harder than 44% of counties.
Softest in Texas: Nacogdoches County at 0.3 gpg. Hardest: Ward County at 218.5 gpg. Closest to Dallas County: Borden County (8.4), Harris County (8.4), Fort Bend County (8.5).