Sinkhole risk in Cheyenne 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: 19%
At or near the surface: 19%
Buried under cover: 0%

The next step for one property

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 194 of Cheyenne County's 1,020 square miles on soluble rock, 194 of them with the rock at or near the surface. With about 2,646 residents (3 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 384 map points about 1.6 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 the signs to look for and how an inspection works.

Counties around Cheyenne County

The nearest county rated sinkhole country is Harlan County, NE, about 126 miles east. 3 of the 6 closest counties land in the same band; the ground changes quickly around here.

Dundy County, NE 27 mi north · 17% at surface
Sherman County, KS 30 mi south · 9% at surface
Rawlins County, KS 35 mi east · 24% at surface
Yuma County, CO 40 mi west · 7% at surface
Hitchcock County, NE 45 mi northeast · 20% at surface
Thomas County, KS 45 mi southeast · 8% at surface

The rock underneath

The largest mapped soluble unit here is the Ogallala Formation (arkose), Miocene in age, covering about 17% of the county. Next is the Pierre Shale at 2%.

2% of the county sits on gypsum or salt, which dissolves in years rather than millennia. That share matters more than its size suggests.

Against the rest of Kansas

Cheyenne County ranks 60 of 105 in Kansas for soluble rock at the surface, and sits above 74% of US counties on that measure.