Sinkhole risk in Kearney County, NE: Sinkhole country

Sinkhole country

Fast-dissolving gypsum or salt beds under a large part of the county.

On soluble rock: 47%
At or near the surface: 47%
Buried under cover: 0%

What this means before you buy

Get a sinkhole or geotechnical inspection before buying, building or adding weight to a foundation.

That works out to roughly 244 of Kearney County's 516 square miles on soluble rock, 244 of them with the rock at or near the surface. With about 6,749 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 368 map points about 1.2 miles apart, so a pocket smaller than that can be missed or overstated.

Two things to read before deciding: why gypsum and salt move faster than limestone, and the signs to look for and how an inspection works.

Counties around Kearney County

The closest county with no soluble rock mapped is Phelps County, NE, about 24 miles west. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

Franklin County, NE 23 mi south · 78% at surface
Adams County, NE 24 mi east · 79% at surface
Phelps County, NE 24 mi west · 0% at surface
Buffalo County, NE 25 mi north · 4% at surface
Webster County, NE 33 mi southeast · 78% at surface
Harlan County, NE 33 mi southwest · 37% at surface

The rock underneath

The largest mapped soluble unit here is the Pierre Shale (shale), Late Cretaceous in age, covering about 47% of the county.

47% of the county sits on gypsum or salt, which dissolves in years rather than millennia. That share matters more than its size suggests.

Against the rest of Nebraska

Kearney County ranks 9 of 93 in Nebraska for soluble rock at the surface, and sits above 87% of US counties on that measure.