Sinkhole risk in Stafford County, VA: Pockets of it

Pockets of it

Soluble rock at the surface or under thin cover in part of the county.

On soluble rock: 23%
At or near the surface: 23%
Buried under cover: 0%

The next step for one property

Check the parcel against your state survey sinkhole map, and ask for an inspection if cracks, depressions or sticking doors show up.

That works out to roughly 62 of Stafford County's 268 square miles on soluble rock, 62 of them with the rock at or near the surface. With about 168,919 residents (629 per square mile), most of the county is built up, so a mapped unit is likely to sit under somebody's street. The figures come from 254 map points about 1.0 miles apart, so a pocket smaller than that can be missed or overstated.

Worth reading for this county: the signs to look for and how an inspection works, and how these percentages are measured.

Counties around Stafford County

The nearest county rated sinkhole country is Clarke County, VA, about 56 miles northwest. 1 of the 6 closest counties land in the same band; the ground changes quickly around here.

Fredericksburg city, VA 9 mi south · 10% at surface
King George County, VA 19 mi southeast · 45% at surface
Prince William County, VA 19 mi north · 2% at surface
Spotsylvania County, VA 20 mi southwest · 5% at surface
Manassas city, VA 22 mi north · under 1% at surface
Manassas Park city, VA 24 mi north · 0% at surface

The rock underneath

The largest mapped soluble unit here is the Lower Tertiary Deposits (sand), Tertiary in age, covering about 16% of the county. Next is the Chesapeake Group at 8%.

Against the rest of Virginia

Stafford County ranks 42 of 133 in Virginia for soluble rock at the surface, and sits above 76% of US counties on that measure.