Sinkhole risk in Nevada County, CA: Not karst, but voids possible

Not karst, but voids possible

No soluble bedrock; some pseudokarst (piping or lava-tube ground).

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

What this means before you buy

Not true karst, but soil piping or lava tubes can still open voids - mention it to an inspector.

Across 958 square miles, under one square mile of Nevada County maps onto soluble rock. With about 102,195 residents (107 per square mile), homes are spread across towns and farmland, and a mapped unit may or may not reach the developed parts. The figures come from 400 map points about 1.5 miles apart, so a pocket smaller than that can be missed or overstated.

Worth reading for this county: how ground with no limestone still opens up, and how these percentages are measured.

Counties around Nevada County

The nearest county rated sinkhole country is Emery County, UT, about 539 miles east. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

Placer County, CA 16 mi south · 0% at surface
Sierra County, CA 23 mi northeast · 0% at surface
Yuba County, CA 31 mi west · 0% at surface
El Dorado County, CA 38 mi south · 0% at surface
Plumas County, CA 48 mi north · 0% at surface
Butte County, CA 51 mi northwest · under 1% at surface

Against the rest of California

Nevada County ranks 44 of 58 in California for soluble rock at the surface, and sits above 0% of US counties on that measure.