Sinkhole risk in Hays 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: 88%
At or near the surface: 88%
Buried under cover: 0%

What to do about a house in Hays County

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 594 of Hays County's 677 square miles on soluble rock, 594 of them with the rock at or near the surface. With about 292,029 residents (431 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 479 map points about 1.2 miles apart, so a pocket smaller than that can be missed or overstated.

Counties around Hays County

The nearest county rated sinkhole country is Runnels County, TX, about 169 miles northwest. 4 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Comal County, TX 22 mi southwest · 92% at surface
Travis County, TX 24 mi northeast · 57% at surface
Blanco County, TX 26 mi northwest · 90% at surface
Caldwell County, TX 29 mi southeast · 8% at surface
Guadalupe County, TX 33 mi south · 9% at surface
Kendall County, TX 41 mi west · 98% at surface

What Hays County is built on

The largest mapped soluble unit here is the Glen Rose Limestone (limestone), Early Cretaceous in age, covering about 48% of the county. Next is the Edwards Limestone at 23%.

Against the rest of Texas

Hays County ranks 15 of 254 in Texas for soluble rock at the surface, and sits above 96% of US counties on that measure.