Sinkhole risk in Transylvania County, NC: Mostly deep or small

Mostly deep or small

Some soluble rock, mostly deeply buried or in a small share of the county.

On soluble rock: 5%
At or near the surface: 5%
Buried under cover: 0%

What this means before you buy

Sinkholes are uncommon here; watch for new depressions after heavy rain or leaking pipes.

That works out to roughly 20 of Transylvania County's 378 square miles on soluble rock, 20 of them with the rock at or near the surface. With about 34,103 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 521 map points about 0.9 miles apart, so a pocket smaller than that can be missed or overstated.

Worth reading for this county: how these percentages are measured, and the warning signs that apply anywhere.

Counties around Transylvania County

The nearest county rated sinkhole country is Cocke County, TN, about 52 miles north. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

Jackson County, NC 18 mi west · 0% at surface
Henderson County, NC 21 mi northeast · 3% at surface
Pickens County, SC 23 mi south · 0% at surface
Haywood County, NC 26 mi north · under 1% at surface
Buncombe County, NC 32 mi northeast · 3% at surface
Greenville County, SC 33 mi southeast · 0% at surface

Which formation it is

The largest mapped soluble unit here is the Rocks of Brevard Fault Zone (schist), Uncertain, possibly Permian or Devonian in age, covering about 5% of the county.

Against the rest of North Carolina

Transylvania County ranks 46 of 100 in North Carolina for soluble rock at the surface, and sits above 63% of US counties on that measure.