Sinkhole risk in Davison County, SD: Pockets of it

Pockets of it

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

On soluble rock: 61%
At or near the surface: 0%
Buried under cover: 61%

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 265 of Davison County's 436 square miles on soluble rock. With about 19,907 residents (46 per square mile), much of the land is open, and the mapped rock may sit far from where people actually live. The figures come from 400 map points about 1.0 miles apart, so a pocket smaller than that can be missed or overstated.

Worth reading for this county: why the 61% under cover still counts, and the signs to look for and how an inspection works.

Counties around Davison County

The nearest county rated sinkhole country is Boyd County, NE, about 63 miles southwest. None of the 6 closest counties land in the same band, so Davison County stands out from its surroundings.

Hanson County, SD 18 mi east · 0% at surface
Aurora County, SD 21 mi west · 0% at surface
Douglas County, SD 22 mi southwest · 0% at surface
Sanborn County, SD 24 mi north · 0% at surface
Hutchinson County, SD 31 mi southeast · 0% at surface
Jerauld County, SD 35 mi northwest · 0% at surface

Which formation it is

The largest mapped soluble unit here is the Niobrara Formation (limestone), Late Cretaceous in age, covering about 61% of the county.

Against the rest of South Dakota

Davison County ranks 24 of 66 in South Dakota for soluble rock at the surface, and sits above 0% of US counties on that measure.