Sinkhole risk in Dakota County, MN: 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: 87%
At or near the surface: 0%
Buried under cover: 87%

What this means before you buy

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

That works out to roughly 488 of Dakota County's 563 square miles on soluble rock. With about 453,156 residents (806 per square mile), most of the county is built up, so a mapped unit is likely to sit under somebody's street. The figures come from 258 map points about 1.5 miles apart, so a pocket smaller than that can be missed or overstated.

Counties around Dakota County

The nearest county rated sinkhole country is Vernon County, WI, about 134 miles southeast. 5 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Scott County, MN 23 mi west · 0% at surface
Ramsey County, MN 24 mi north · 0% at surface
Rice County, MN 25 mi southwest · 0% at surface
Goodhue County, MN 25 mi southeast · 22% at surface
Washington County, MN 27 mi north · 0% at surface
Hennepin County, MN 31 mi northwest · 0% at surface

Which formation it is

The largest mapped soluble unit here is the Lower Ordovician rocks, undivided (dolostone (dolomite)), Lower Ordovician in age, covering about 57% of the county. Next is the Middle Ordovician rocks, undivided at 29%.

Against the rest of Minnesota

Dakota County ranks 26 of 87 in Minnesota for soluble rock at the surface, and sits above 0% of US counties on that measure.