Sinkhole risk in Clay County, MS: Sinkhole country

Sinkhole country

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

On soluble rock: 94%
At or near the surface: 94%
Buried under cover: 0%

The next step for one property

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

That works out to roughly 386 of Clay County's 410 square miles on soluble rock, 386 of them with the rock at or near the surface. With about 18,213 residents (44 per square mile), there is effectively nowhere in the county off the soluble rock, town or country. The figures come from 628 map points about 0.8 miles apart, so a pocket smaller than that can be missed or overstated.

Worth reading for this county: the signs to look for and how an inspection works, and how these percentages are measured.

Counties around Clay County

The closest county with no soluble rock mapped is Choctaw County, MS, about 35 miles southwest. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

Oktibbeha County, MS 17 mi south · 94% at surface
Chickasaw County, MS 21 mi northwest · 93% at surface
Monroe County, MS 23 mi northeast · 31% at surface
Lowndes County, MS 24 mi southeast · 44% at surface
Webster County, MS 29 mi west · 7% at surface
Choctaw County, MS 35 mi southwest · 0% at surface

The rock underneath

The largest mapped soluble unit here is the Demopolis chalk (carbonate), Upper Cretaceous in age, covering about 47% of the county. Next is the Mooreville chalk at 13%.

Against the rest of Mississippi

Clay County ranks 1 of 82 in Mississippi for soluble rock at the surface, and sits above 98% of US counties on that measure.