SinkholeOdds

Sinkhole risk in Wasatch County, UT: Pockets of it

Pockets of it

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

On soluble rock
18%
At or near the surface
18%
Buried under cover
0%

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.

That works out to roughly 207 of Wasatch County's 1,177 square miles on soluble rock, 207 of them with the rock at or near the surface. With about 37,858 residents (32 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 597 map points about 1.4 miles apart, so a pocket smaller than that can be missed or overstated.

Read next: why gypsum and salt move faster than limestone, and the signs to look for and how an inspection works.

Counties around Wasatch County

The nearest county rated sinkhole country is Emery County, UT, about 95 miles south. 1 of the 6 closest counties land in the same band; the ground changes quickly around here.

The rock underneath

The largest mapped soluble unit here is the Pennsylvanian and Permian sedimentary rocks in central Utah (sandstone), Pennsylvanian to Permian in age, covering about 10% of the county. Next is the Mississippian (2) sedimentary rocks in Uinta Mountains-Uinta Basin region at 2%.

3% of the county sits on gypsum or salt, which dissolves in years rather than millennia. That share matters more than its size suggests.

The county also lies over the Sevire Valley, 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 Utah

Wasatch County ranks 6 of 29 in Utah for soluble rock at the surface, and sits above 73% of US counties on that measure.