SinkholeOdds

Sinkhole risk in Wayne County, IA: No soluble rock mapped

No soluble rock mapped

No soluble bedrock mapped.

On soluble rock
under 1%
At or near the surface
0%
Buried under cover
under 1%

The next step for one property

No soluble bedrock is mapped here, so natural sinkholes are unlikely. Collapses from broken pipes or old mines are a separate risk.

That works out to roughly 1 of Wayne County's 525 square miles on soluble rock. With about 6,622 residents (13 per square mile), much of the land is open, and the mapped rock may sit far from where people actually live. The figures come from 408 map points about 1.1 miles apart, so a pocket smaller than that can be missed or overstated.

Read next: why gypsum and salt move faster than limestone, and how these percentages are measured.

Counties around Wayne County

The nearest county rated sinkhole country is Jackson County, MO, about 131 miles southwest. 3 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 Marmaton Group (shale), Middle Pennsylvanian-Des Moines Series in age, covering about under 1% of the county.

The county also lies over the Forest City Basin, 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 Iowa

Wayne County ranks 94 of 99 in Iowa for soluble rock at the surface, and sits above 0% of US counties on that measure.