SinkholeOdds

Sinkhole risk in Tom Green County, TX: Pockets of it

Pockets of it

Soluble rock at the surface or under thin cover in part of the county.

On soluble rock
35%
At or near the surface
35%
Buried under cover
0%

The next step for one property

Check the parcel against your state survey sinkhole map, and ask for an inspection if cracks, depressions or sticking doors show up.

That works out to roughly 533 of Tom Green County's 1,522 square miles on soluble rock, 533 of them with the rock at or near the surface. With about 120,103 residents (79 per square mile), homes are spread across towns and farmland, and a mapped unit may or may not reach the developed parts. The figures come from 543 map points about 1.7 miles apart, so a pocket smaller than that can be missed or overstated.

Two things to read before deciding: why gypsum and salt move faster than limestone, and the signs to look for and how an inspection works.

Counties around Tom Green County

The nearest county rated sinkhole country is Coke County, TX, about 35 miles north, close enough that the same rock may run under the county line. 4 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

The rock underneath

The largest mapped soluble unit here is the Edwards Limestone (limestone), Early Cretaceous in age, covering about 32% of the county. Next is the San Angelo Formation at 2%.

3% of the county sits on gypsum or salt, which dissolves in years rather than millennia. That share matters more than its size suggests.

The county also lies over the Permian Basin, Anadarko Basin,Dalhart Basin, Palo Duro Basin, a deep salt or gypsum basin. Deep beds rarely cause surface collapse on their own, but wells and mining into them have.

Against the rest of Texas

Tom Green County ranks 77 of 254 in Texas for soluble rock at the surface, and sits above 82% of US counties on that measure.