Sinkhole risk in Walker County, GA: Sinkhole country

Sinkhole country

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

On soluble rock: 66%
At or near the surface: 66%
Buried under cover: 0%

What to do about a house in Walker County

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

That works out to roughly 294 of Walker County's 446 square miles on soluble rock, 294 of them with the rock at or near the surface. With about 69,340 residents (155 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 622 map points about 0.8 miles apart, so a pocket smaller than that can be missed or overstated.

Counties around Walker County

The closest county with no soluble rock mapped is Gilmer County, GA, about 48 miles east. 5 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Dade County, GA 14 mi northwest · 39% at surface
Catoosa County, GA 15 mi northeast · 63% at surface
Chattooga County, GA 18 mi south · 59% at surface
Whitfield County, GA 20 mi east · 74% at surface
Gordon County, GA 29 mi southeast · 61% at surface
Hamilton County, TN 30 mi north · 70% at surface

The rock underneath

The largest mapped soluble unit here is the Knox Group undifferentiated (dolostone (dolomite)), Ordovician-Cambrian in age, covering about 26% of the county. Next is the Chickamauga Group undivided at 12%.

Against the rest of Georgia

Walker County ranks 11 of 159 in Georgia for soluble rock at the surface, and sits above 91% of US counties on that measure.