Sinkhole risk in Cassia County, ID: 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: 7%
At or near the surface: 7%
Buried under cover: 0%

The next step for one property

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

That works out to roughly 187 of Cassia County's 2,566 square miles on soluble rock, 187 of them with the rock at or near the surface. With about 25,976 residents (10 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 327 map points about 2.8 miles apart, so a pocket smaller than that can be missed or overstated.

Worth reading for this county: how these percentages are measured, and the warning signs that apply anywhere.

Counties around Cassia County

The nearest county rated sinkhole country is Emery County, UT, about 273 miles southeast. 1 of the 6 closest counties land in the same band; the ground changes quickly around here.

Minidoka County, ID 40 mi north · 0% at surface
Jerome County, ID 43 mi northwest · 0% at surface
Power County, ID 49 mi northeast · 18% at surface
Twin Falls County, ID 53 mi west · under 1% at surface
Box Elder County, UT 54 mi southeast · 12% at surface
Lincoln County, ID 56 mi northwest · 0% at surface

Which formation it is

The largest mapped soluble unit here is the Limestone, sandstone, dolostone, and chert; Permian to Pennsylvanian marine epicontinental-basin deposits; southeastern Idaho; (limestone), Early Permian to Early Pennsylvanian in age, covering about 3% of the county. Next is the Limestone, sandstone, shale, and chert; Pennsylvanian marine epicontinental-basin deposits; southeastern Idaho at 2%.

Against the rest of Idaho

Cassia County ranks 15 of 44 in Idaho for soluble rock at the surface, and sits above 65% of US counties on that measure.