Sinkhole risk in Montgomery 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: 8%
At or near the surface: 8%
Buried under cover: 0%

The next step for one property

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

That works out to roughly 40 of Montgomery County's 492 square miles on soluble rock, 40 of them with the rock at or near the surface. With about 26,364 residents (54 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 244 map points about 1.4 miles apart, so a pocket smaller than that can be missed or overstated.

Two things to read before deciding: how these percentages are measured, and the warning signs that apply anywhere.

Counties around Montgomery County

The nearest county rated sinkhole country is Scotland County, NC, about 42 miles southeast. 1 of the 6 closest counties land in the same band; the ground changes quickly around here.

Stanly County, NC 19 mi west · 0% at surface
Moore County, NC 24 mi east · 36% at surface
Richmond County, NC 24 mi south · 20% at surface
Anson County, NC 27 mi southwest · 2% at surface
Randolph County, NC 27 mi north · 0% at surface
Davidson County, NC 36 mi northwest · 0% at surface

What Montgomery County is built on

The largest mapped soluble unit here is the Middendorf Formation (sand), Cretaceous in age, covering about 8% of the county.

Against the rest of North Carolina

Montgomery County ranks 44 of 100 in North Carolina for soluble rock at the surface, and sits above 66% of US counties on that measure.