Sinkhole risk in Montgomery County, KS: Sinkhole country

Sinkhole country

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

On soluble rock: 72%
At or near the surface: 72%
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 466 of Montgomery County's 644 square miles on soluble rock, 466 of them with the rock at or near the surface. With about 30,459 residents (47 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.

Counties around Montgomery County

The closest county with no soluble rock mapped is Noble County, OK, about 100 miles southwest. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

Labette County, KS 24 mi east · 74% at surface
Wilson County, KS 25 mi north · 54% at surface
Chautauqua County, KS 28 mi west · 38% at surface
Nowata County, OK 29 mi south · 34% at surface
Elk County, KS 33 mi northwest · 53% at surface
Washington County, OK 35 mi south · 9% at surface

Which formation it is

The largest mapped soluble unit here is the Kansas City Group (limestone), Middle Pennsylvanian- Missourian in age, covering about 49% of the county. Next is the Lansing Group at 13%.

Against the rest of Kansas

Montgomery County ranks 13 of 105 in Kansas for soluble rock at the surface, and sits above 93% of US counties on that measure.