SinkholeOdds

Sinkhole risk in Gadsden County, FL: Pockets of it

Pockets of it

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

On soluble rock
100%
At or near the surface
33%
Buried under cover
67%

What this means before you buy

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

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 516 of Gadsden County's 516 square miles on soluble rock, 169 of them with the rock at or near the surface. With about 44,151 residents (86 per square mile), there is effectively nowhere in the county off the soluble rock, town or country. The figures come from 245 map points about 1.5 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 gypsum and salt move faster than limestone.

Counties around Gadsden County

The nearest county rated sinkhole country is Decatur County, GA, about 21 miles north, close enough that the same rock may run under the county line. 4 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Which formation it is

The largest mapped soluble unit here is the Hawthorn Group, Torreya Formation (limestone), Eocene in age, covering about 67% of the county. Next is the Hawthorn Group, Torreya Formation at 31%.

The county also lies over the Floridan shelf, a deep salt or gypsum basin. Deep beds rarely cause surface collapse on their own, but wells and mining into them have.

Against the rest of Florida

Gadsden County ranks 41 of 67 in Florida for soluble rock at the surface, and sits above 81% of US counties on that measure.