Sinkhole risk in Douglas County, KS: Pockets of it

Pockets of it

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

On soluble rock: 42%
At or near the surface: 23%
Buried under cover: 19%

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 191 of Douglas County's 456 square miles on soluble rock, 103 of them with the rock at or near the surface. With about 121,989 residents (268 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 339 map points about 1.2 miles apart, so a pocket smaller than that can be missed or overstated.

Worth reading for this county: why the 19% under cover still counts, and the signs to look for and how an inspection works.

Counties around Douglas County

The nearest county rated sinkhole country is Johnson County, KS, about 25 miles east, 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.

Franklin County, KS 23 mi south · 33% at surface
Jefferson County, KS 24 mi north · 0% at surface
Leavenworth County, KS 24 mi northeast · 0% at surface
Johnson County, KS 25 mi east · 67% at surface
Shawnee County, KS 27 mi west · 4% at surface
Osage County, KS 28 mi southwest · 41% at surface

The rock underneath

The largest mapped soluble unit here is the Shawnee Group (limestone), Late Pennsylvanian- Virgilian in age, covering about 41% of the county. Next is the Lansing Group at 1%.

Against the rest of Kansas

Douglas County ranks 51 of 105 in Kansas for soluble rock at the surface, and sits above 76% of US counties on that measure.