Sinkhole risk in Shelby County, MO: Mostly deep or small

Mostly deep or small

Some soluble rock, mostly deeply buried or in a small share of the county.

On soluble rock: 65%
At or near the surface: 0%
Buried under cover: 65%

What to do about a house in Shelby County

Sinkholes are uncommon here; watch for new depressions after heavy rain or leaking pipes.

That works out to roughly 323 of Shelby County's 501 square miles on soluble rock. With about 5,926 residents (12 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 338 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 65% under cover still counts, and how these percentages are measured.

Counties around Shelby County

The nearest county rated sinkhole country is Cooper County, MO, about 76 miles southwest. 5 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Monroe County, MO 21 mi south · 7% at surface
Knox County, MO 24 mi north · 0% at surface
Marion County, MO 24 mi east · 0% at surface
Macon County, MO 25 mi west · 0% at surface
Lewis County, MO 28 mi northeast · 0% at surface
Randolph County, MO 33 mi southwest · 0% at surface

What Shelby County is built on

The largest mapped soluble unit here is the Osagean Series (limestone), Early Mississippian-Osagean Series in age, covering about 65% of the county.

Against the rest of Missouri

Shelby County ranks 113 of 115 in Missouri for soluble rock at the surface, and sits above 0% of US counties on that measure.