SinkholeOdds

Sinkhole risk in Ellis 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
33%
At or near the surface
33%
Buried under cover
0%

What this means before you buy

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 310 of Ellis County's 936 square miles on soluble rock, 310 of them with the rock at or near the surface. With about 232,387 residents (248 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 275 map points about 1.8 miles apart, so a pocket smaller than that can be missed or overstated.

Read next: why gypsum and salt move faster than limestone, and the signs to look for and how an inspection works.

Counties around Ellis County

The nearest county rated sinkhole country is Baylor County, TX, about 165 miles northwest. 4 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

What Ellis County is built on

The largest mapped soluble unit here is the Austin Chalk (limestone), Late Cretaceous; Gulfian Series in age, covering about 33% of the county.

The county also lies over the Gulf Coast salt domes, 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

Ellis County ranks 79 of 254 in Texas for soluble rock at the surface, and sits above 81% of US counties on that measure.