Sinkhole risk in Dubois 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: 6%
At or near the surface: 5%
Buried under cover: under 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 25 of Dubois County's 427 square miles on soluble rock, 21 of them with the rock at or near the surface. With about 43,629 residents (102 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 360 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 Dubois County

The nearest county rated sinkhole country is Orange County, IN, about 24 miles northeast, close enough that the same rock may run under the county line. None of the 6 closest counties land in the same band, so Dubois County stands out from its surroundings.

Pike County, IN 20 mi west · 0% at surface
Martin County, IN 23 mi north · 23% at surface
Orange County, IN 24 mi northeast · 90% at surface
Crawford County, IN 24 mi east · 83% at surface
Perry County, IN 24 mi southeast · 49% at surface
Daviess County, IN 25 mi northwest · 0% at surface

The rock underneath

The largest mapped soluble unit here is the Stephensport Group (sandstone), Mississippian in age, covering about 4% of the county. Next is the Buffalo Wallow Group at 2%.

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

Dubois County ranks 18 of 92 in Indiana for soluble rock at the surface, and sits above 63% of US counties on that measure.