Sinkhole risk in Warren County, MO: Pockets of it

Pockets of it

Soluble rock at the surface or under thin cover in part of the county.

On soluble rock: 90%
At or near the surface: 42%
Buried under cover: 48%

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 385 of Warren County's 429 square miles on soluble rock, 180 of them with the rock at or near the surface. With about 38,478 residents (90 per square mile), homes are spread across towns and farmland, and a mapped unit may or may not reach the developed parts. The figures come from 579 map points about 0.9 miles apart, so a pocket smaller than that can be missed or overstated.

Counties around Warren County

The nearest county rated sinkhole country is Franklin County, MO, about 25 miles south, close enough that the same rock may run under the county line. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

Montgomery County, MO 20 mi northwest · 30% at surface
Lincoln County, MO 23 mi northeast · 0% at surface
Franklin County, MO 25 mi south · 96% at surface
St. Charles County, MO 26 mi east · 14% at surface
Gasconade County, MO 29 mi southwest · 97% at surface
Calhoun County, IL 38 mi northeast · 51% at surface

The rock underneath

The largest mapped soluble unit here is the Osagean Series (limestone), Early Mississippian-Osagean Series in age, covering about 49% of the county. Next is the Smithville Dolomite, Powell Dolomite, Cotter Dolomite, Jefferson City Dolomite at 12%.

Against the rest of Missouri

Warren County ranks 61 of 115 in Missouri for soluble rock at the surface, and sits above 85% of US counties on that measure.