Sinkhole risk in Clay County, IN: Mostly deep or small

Mostly deep or small

Some soluble rock, mostly deeply buried or in a small share of the county.

On soluble rock: 1%
At or near the surface: 0%
Buried under cover: 1%

The next step for one property

Sinkholes are uncommon here; watch for new depressions after heavy rain or leaking pipes.

That works out to roughly 5 of Clay County's 358 square miles on soluble rock. With about 26,424 residents (74 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 296 map points about 1.1 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 how these percentages are measured.

Counties around Clay County

The nearest county rated sinkhole country is Monroe County, IN, about 36 miles southeast, close enough that the same rock may run under the county line. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

Vigo County, IN 15 mi west · 0% at surface
Owen County, IN 16 mi east · 16% at surface
Putnam County, IN 23 mi northeast · under 1% at surface
Greene County, IN 25 mi south · 20% at surface
Sullivan County, IN 26 mi southwest · 0% at surface
Parke County, IN 27 mi north · under 1% at surface

What Clay County is built on

The largest mapped soluble unit here is the Blue River Group (limestone), Mississippian in age, covering about 1% of the county.

The county also lies over the Illinois 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 Indiana

Clay County ranks 41 of 92 in Indiana for soluble rock at the surface, and sits above 0% of US counties on that measure.