Sinkhole risk in Decatur County, IN: Pockets of it

Pockets of it

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

On soluble rock: 100%
At or near the surface: 2%
Buried under cover: 98%

What to do about a house in Decatur 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 373 of Decatur County's 373 square miles on soluble rock, 7 of them with the rock at or near the surface. With about 26,421 residents (71 per square mile), there is effectively nowhere in the county off the soluble rock, town or country. The figures come from 322 map points about 1.1 miles apart, so a pocket smaller than that can be missed or overstated.

Worth reading for this county: why the 98% under cover still counts, and the signs to look for and how an inspection works.

Counties around Decatur County

The nearest county rated sinkhole country is Monroe County, IN, about 56 miles west. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

Ripley County, IN 19 mi southeast · 6% at surface
Shelby County, IN 22 mi northwest · 0% at surface
Rush County, IN 22 mi north · 0% at surface
Bartholomew County, IN 22 mi west · 0% at surface
Jennings County, IN 22 mi south · 7% at surface
Franklin County, IN 24 mi east · 2% at surface

What Decatur County is built on

The largest mapped soluble unit here is the Louisville Limestone through Brassfield Limestone (limestone), Silurian in age, covering about 57% of the county. Next is the Muscatatuck Group at 36%.

Against the rest of Indiana

Decatur County ranks 23 of 92 in Indiana for soluble rock at the surface, and sits above 57% of US counties on that measure.