Sinkhole risk in Franklin County, KY: Pockets of it

Pockets of it

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

On soluble rock: 47%
At or near the surface: 47%
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 98 of Franklin County's 208 square miles on soluble rock, 98 of them with the rock at or near the surface. With about 52,442 residents (252 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 280 map points about 0.9 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 Franklin County

The nearest county rated sinkhole country is Woodford County, KY, about 15 miles southeast, close enough that the same rock may run under the county line. 3 of the 6 closest counties land in the same band; the ground changes quickly around here.

Woodford County, KY 15 mi southeast · 99% at surface
Scott County, KY 16 mi east · 57% at surface
Anderson County, KY 17 mi south · 25% at surface
Owen County, KY 18 mi north · 33% at surface
Shelby County, KY 20 mi west · 68% at surface
Henry County, KY 20 mi northwest · 48% at surface

What Franklin County is built on

The largest mapped soluble unit here is the Lexington Limestone (limestone), Ordovician in age, covering about 46% of the county. Next is the Ashlock Formation, Grant Lake and Calloway Creek Limestones, and Fairview Formation, undivided at 1%.

Against the rest of Kentucky

Franklin County ranks 45 of 120 in Kentucky for soluble rock at the surface, and sits above 86% of US counties on that measure.