Sinkhole risk in Door County, WI: Pockets of it

Pockets of it

Soluble rock at the surface or under thin cover in part of the county.

On soluble rock: 87%
At or near the surface: under 1%
Buried under cover: 86%

What to do about a house in Door County

Check the parcel against your state survey sinkhole map, and ask for an inspection if cracks, depressions or sticking doors show up.

That works out to roughly 419 of Door County's 482 square miles on soluble rock, 4 of them with the rock at or near the surface. With about 30,512 residents (63 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 569 map points about 0.9 miles apart, so a pocket smaller than that can be missed or overstated.

Counties around Door County

The nearest county rated sinkhole country is Wexford County, MI, about 90 miles southeast. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

Menominee County, MI 38 mi northwest · under 1% at surface
Kewaunee County, WI 39 mi southwest · 0% at surface
Leelanau County, MI 49 mi east · 7% at surface
Marinette County, WI 49 mi west · 0% at surface
Delta County, MI 50 mi north · 0% at surface
Benzie County, MI 51 mi southeast · 0% at surface

Which formation it is

The largest mapped soluble unit here is the Silurian, undivided (dolostone (dolomite)), Silurian in age, covering about 84% of the county. Next is the Maquoketa Formation at 3%.

Against the rest of Wisconsin

Door County ranks 19 of 72 in Wisconsin for soluble rock at the surface, and sits above 55% of US counties on that measure.