Sinkhole risk in Geneva County, AL: Sinkhole country

Sinkhole country

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

On soluble rock: 82%
At or near the surface: 51%
Buried under cover: 31%

What to do about a house in Geneva County

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

That works out to roughly 469 of Geneva County's 574 square miles on soluble rock, 294 of them with the rock at or near the surface. With about 27,259 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 389 map points about 1.2 miles apart, so a pocket smaller than that can be missed or overstated.

Two things to read before deciding: why the 31% under cover still counts, and the signs to look for and how an inspection works.

Counties around Geneva County

The closest county with no soluble rock mapped is Quitman County, GA, about 72 miles northeast. 3 of the 6 closest counties land in the same band; the ground changes quickly around here.

Holmes County, FL 16 mi south · 66% at surface
Coffee County, AL 24 mi northwest · 2% at surface
Dale County, AL 27 mi northeast · 7% at surface
Houston County, AL 31 mi east · 84% at surface
Washington County, FL 35 mi south · 54% at surface
Covington County, AL 39 mi west · 4% at surface

The rock underneath

The largest mapped soluble unit here is the Claiborne/Jackson Group; Residuum (residuum), Eocene-Oligocene in age, covering about 42% of the county. Next is the Jackson Group undifferentiated at 30%.

Against the rest of Alabama

Geneva County ranks 10 of 67 in Alabama for soluble rock at the surface, and sits above 88% of US counties on that measure.