Sinkhole risk in Coffey County, KS: Sinkhole country

Sinkhole country

Soluble rock at or near the surface across much of the county.

On soluble rock: 53%
At or near the surface: 53%
Buried under cover: 0%

What this means before you buy

Get a sinkhole or geotechnical inspection before buying, building or adding weight to a foundation.

That works out to roughly 333 of Coffey County's 627 square miles on soluble rock, 333 of them with the rock at or near the surface. With about 8,301 residents (13 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 399 map points about 1.3 miles apart, so a pocket smaller than that can be missed or overstated.

Two things to read before deciding: the signs to look for and how an inspection works, and how these percentages are measured.

Counties around Coffey County

The closest county with no soluble rock mapped is Nemaha County, NE, about 149 miles north. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

Anderson County, KS 24 mi east · 55% at surface
Woodson County, KS 24 mi south · 40% at surface
Lyon County, KS 28 mi northwest · 39% at surface
Osage County, KS 29 mi north · 41% at surface
Franklin County, KS 33 mi northeast · 33% at surface
Allen County, KS 34 mi southeast · 90% at surface

The rock underneath

The largest mapped soluble unit here is the Shawnee Group (limestone), Late Pennsylvanian- Virgilian in age, covering about 53% of the county.

Against the rest of Kansas

Coffey County ranks 26 of 105 in Kansas for soluble rock at the surface, and sits above 88% of US counties on that measure.