Sinkhole risk in Spencer County, KY: Sinkhole country

Sinkhole country

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

On soluble rock: 56%
At or near the surface: 56%
Buried under cover: 0%

The next step for one property

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

That works out to roughly 105 of Spencer County's 187 square miles on soluble rock, 105 of them with the rock at or near the surface. With about 20,823 residents (112 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 588 map points about 0.6 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 Spencer County

The closest county with no soluble rock mapped is Laurel County, KY, about 91 miles southeast. 3 of the 6 closest counties land in the same band; the ground changes quickly around here.

Shelby County, KY 16 mi north · 68% at surface
Nelson County, KY 17 mi southwest · 56% at surface
Anderson County, KY 18 mi east · 25% at surface
Washington County, KY 20 mi south · 42% at surface
Bullitt County, KY 21 mi west · 42% at surface
Jefferson County, KY 22 mi northwest · 59% at surface

What Spencer County is built on

The largest mapped soluble unit here is the Ashlock Formation, Grant Lake and Calloway Creek Limestones, and Fairview Formation, undivided (limestone), Ordovician in age, covering about 49% of the county. Next is the Drakes Formation at 7%.

Against the rest of Kentucky

Spencer County ranks 34 of 120 in Kentucky for soluble rock at the surface, and sits above 89% of US counties on that measure.