Sinkhole risk in Lancaster County, VA: 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: 4%
At or near the surface: 4%
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 6 of Lancaster County's 133 square miles on soluble rock, 6 of them with the rock at or near the surface. With about 11,062 residents (83 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 550 map points about 0.5 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 Lancaster County

The nearest county rated sinkhole country is Hertford County, NC, about 98 miles south. 3 of the 6 closest counties land in the same band; the ground changes quickly around here.

Middlesex County, VA 9 mi southwest · 14% at surface
Northumberland County, VA 11 mi north · 12% at surface
Mathews County, VA 21 mi south · 0% at surface
Gloucester County, VA 22 mi south · 8% at surface
Richmond County, VA 24 mi northwest · 23% at surface
King and Queen County, VA 27 mi west · 37% at surface

The rock underneath

The largest mapped soluble unit here is the Chesapeake Group (sand), Tertiary in age, covering about 4% of the county.

Against the rest of Virginia

Lancaster County ranks 68 of 133 in Virginia for soluble rock at the surface, and sits above 62% of US counties on that measure.