Sinkhole risk in Box Elder County, UT: Mostly deep or small

Mostly deep or small

Some soluble rock, mostly deeply buried or in a small share of the county.

On soluble rock: 12%
At or near the surface: 12%
Buried under cover: 0%

What this means before you buy

Sinkholes are uncommon here; watch for new depressions after heavy rain or leaking pipes.

That works out to roughly 671 of Box Elder County's 5,781 square miles on soluble rock, 671 of them with the rock at or near the surface. With about 64,120 residents (11 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 346 map points about 4.1 miles apart, so a pocket smaller than that can be missed or overstated.

Two things to read before deciding: how these percentages are measured, and the warning signs that apply anywhere.

Counties around Box Elder County

The nearest county rated sinkhole country is Emery County, UT, about 219 miles southeast. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

Oneida County, ID 48 mi northeast · 44% at surface
Cassia County, ID 54 mi northwest · 7% at surface
Davis County, UT 60 mi southeast · under 1% at surface
Weber County, UT 66 mi east · 9% at surface
Cache County, UT 68 mi east · 41% at surface
Franklin County, ID 74 mi northeast · 37% at surface

Which formation it is

The largest mapped soluble unit here is the Pennsylvanian and Permian sedimentary rocks in Logan-Huntsville Allochthon (sandstone), Pennsylvanian to Permian in age, covering about 4% of the county. Next is the Pennsylvanian and Permian sedimentary rocks in western Utah at 2%.

Against the rest of Utah

Box Elder County ranks 12 of 29 in Utah for soluble rock at the surface, and sits above 69% of US counties on that measure.