Sinkhole risk in Crawford County, MO: Sinkhole country

Sinkhole country

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

On soluble rock: 100%
At or near the surface: 100%
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 742 of Crawford County's 742 square miles on soluble rock, 742 of them with the rock at or near the surface. With about 22,808 residents (31 per square mile), there is effectively nowhere in the county off the soluble rock, town or country. The figures come from 343 map points about 1.5 miles apart, so a pocket smaller than that can be missed or overstated.

Counties around Crawford County

The closest county with no soluble rock mapped is Perry County, IL, about 106 miles east. 6 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Washington County, MO 23 mi east · 96% at surface
Phelps County, MO 27 mi west · 100% at surface
Dent County, MO 27 mi south · 100% at surface
Franklin County, MO 34 mi northeast · 96% at surface
Gasconade County, MO 34 mi north · 97% at surface
Maries County, MO 36 mi west · 100% at surface

The rock underneath

The largest mapped soluble unit here is the Gasconade Dolomite (dolostone (dolomite)), Early Ordovician-Ibexian Series in age, covering about 33% of the county. Next is the Roubidoux Formation at 29%.

Against the rest of Missouri

Crawford County ranks 2 of 115 in Missouri for soluble rock at the surface, and sits above 99% of US counties on that measure.