Sinkhole risk in Holmes County, FL: Sinkhole country

Sinkhole country

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

On soluble rock: 100%
At or near the surface: 66%
Buried under cover: 34%

The next step for one property

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

Standard Florida homeowners policies cover only catastrophic ground cover collapse; full sinkhole coverage is a separately priced option insurers must offer.

That works out to roughly 479 of Holmes County's 479 square miles on soluble rock, 315 of them with the rock at or near the surface. With about 19,876 residents (42 per square mile), there is effectively nowhere in the county off the soluble rock, town or country. The figures come from 315 map points about 1.2 miles apart, so a pocket smaller than that can be missed or overstated.

Worth reading for this county: what Florida insurers have to cover, and why the 34% under cover still counts.

Counties around Holmes County

The closest county with no soluble rock mapped is Gulf County, FL, about 76 miles southeast. 4 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Geneva County, AL 16 mi north · 51% at surface
Washington County, FL 20 mi southeast · 54% at surface
Walton County, FL 29 mi southwest · 11% at surface
Jackson County, FL 36 mi east · 87% at surface
Houston County, AL 37 mi northeast · 84% at surface
Coffee County, AL 39 mi north · 2% at surface

The rock underneath

The largest mapped soluble unit here is the Alum Bluff Group (sandstone), Miocene in age, covering about 61% of the county. Next is the Ocala Limestone at 30%.

Against the rest of Florida

Holmes County ranks 19 of 67 in Florida for soluble rock at the surface, and sits above 91% of US counties on that measure.