Sinkhole risk in Frontier County, NE: No soluble rock mapped

No soluble rock mapped

No soluble bedrock mapped.

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

What to do about a house in Frontier County

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 8 of Frontier County's 975 square miles on soluble rock, 8 of them with the rock at or near the surface. With about 2,536 residents (3 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 378 map points about 1.6 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 Frontier County

The nearest county rated sinkhole country is Harlan County, NE, about 58 miles southeast. 4 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Red Willow County, NE 25 mi south · 16% at surface
Gosper County, NE 31 mi east · under 1% at surface
Hayes County, NE 34 mi west · under 1% at surface
Furnas County, NE 35 mi southeast · 32% at surface
Dawson County, NE 39 mi northeast · 0% at surface
Lincoln County, NE 40 mi northwest · 0% at surface

What Frontier County is built on

The largest mapped soluble unit here is the Niobrara Formation (limestone), Late Cretaceous in age, covering about under 1% of the county.

Against the rest of Nebraska

Frontier County ranks 31 of 93 in Nebraska for soluble rock at the surface, and sits above 54% of US counties on that measure.