Sinkhole risk in Bradley County, TN: Sinkhole country

Sinkhole country

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

On soluble rock: 89%
At or near the surface: 89%
Buried under cover: 0%

What to do about a house in Bradley County

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

That works out to roughly 293 of Bradley County's 329 square miles on soluble rock, 293 of them with the rock at or near the surface. With about 113,782 residents (346 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 294 map points about 1.1 miles apart, so a pocket smaller than that can be missed or overstated.

Two things to read before deciding: the signs to look for and how an inspection works, and how these percentages are measured.

Counties around Bradley County

The closest county with no soluble rock mapped is Fannin County, GA, about 37 miles southeast. 5 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Polk County, TN 18 mi east · 20% at surface
Hamilton County, TN 19 mi west · 70% at surface
McMinn County, TN 23 mi northeast · 86% at surface
Catoosa County, GA 24 mi southwest · 63% at surface
Meigs County, TN 25 mi north · 91% at surface
Whitfield County, GA 25 mi south · 74% at surface

What Bradley County is built on

The largest mapped soluble unit here is the Nolichucky Shale, and Maryville, Rogersville, and Rutledge Formations, and Pumpkin Valley Shale (shale), Cambrian in age, covering about 51% of the county. Next is the Copper Ridge Dolomite at 10%.

Against the rest of Tennessee

Bradley County ranks 13 of 95 in Tennessee for soluble rock at the surface, and sits above 97% of US counties on that measure.