Sinkhole risk in Prairie County, MT: No soluble rock mapped

No soluble rock mapped

No soluble bedrock mapped.

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

What this means before you buy

No soluble bedrock is mapped here, so natural sinkholes are unlikely. Collapses from broken pipes or old mines are a separate risk.

Across 1,737 square miles, under one square mile of Prairie County maps onto soluble rock. With about 1,112 residents (1 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 573 map points about 1.7 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 how these percentages are measured.

Counties around Prairie County

The nearest county rated sinkhole country is Fall River County, SD, about 266 miles south. 6 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Custer County, MT 38 mi south · 0% at surface
Dawson County, MT 42 mi northeast · 0% at surface
McCone County, MT 58 mi north · 0% at surface
Wibaux County, MT 59 mi east · 0% at surface
Fallon County, MT 62 mi southeast · 0% at surface
Rosebud County, MT 71 mi southwest · 0% at surface

Against the rest of Montana

Prairie County ranks 48 of 56 in Montana for soluble rock at the surface, and sits above 0% of US counties on that measure.