SinkholeOdds

Sinkhole risk in Walton 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
78%
At or near the surface
11%
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 809 of Walton County's 1,038 square miles on soluble rock, 113 of them with the rock at or near the surface. With about 89,666 residents (86 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 285 map points about 1.9 miles apart, so a pocket smaller than that can be missed or overstated.

Two things to read before deciding: what Florida insurers have to cover, and why gypsum and salt move faster than limestone.

Counties around Walton County

The nearest county rated sinkhole country is Holmes County, FL, about 29 miles northeast, close enough that the same rock may run under the county line. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

Which formation it is

The largest mapped soluble unit here is the Alum Bluff Group (limestone), Eocene in age, covering about 60% of the county. Next is the Alum Bluff Group at 11%.

The county also lies over the Gulf Coast salt domes, 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

Walton County ranks 53 of 67 in Florida for soluble rock at the surface, and sits above 68% of US counties on that measure.