SinkholeOdds

Sinkhole risk in Muskegon County, MI: Sinkhole country

Sinkhole country

Fast-dissolving gypsum or salt beds under a large part of the county.

On soluble rock
38%
At or near the surface
0%
Buried under cover
38%

What to do about a house in Muskegon County

Get a sinkhole or geotechnical inspection before buying, building or adding weight to a foundation.

That works out to roughly 191 of Muskegon County's 504 square miles on soluble rock. With about 177,428 residents (352 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 243 map points about 1.4 miles apart, so a pocket smaller than that can be missed or overstated.

Worth reading for this county: why gypsum and salt move faster than limestone, and why the 38% under cover still counts.

Counties around Muskegon County

The closest county with no soluble rock mapped is Mecosta County, MI, about 56 miles east. 4 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

What Muskegon County is built on

The largest mapped soluble unit here is the Michigan Formation (black shale), Mississippian in age, covering about 35% of the county. Next is the Bayport Limestone at 3%.

35% of the county sits on gypsum or salt, which dissolves in years rather than millennia. That share matters more than its size suggests.

The county also lies over the Michigan Basin; Ohio Basin; Appalachian Basin, a deep salt or gypsum basin. Deep beds rarely cause surface collapse on their own, but wells and mining into them have.

Against the rest of Michigan

Muskegon County ranks 64 of 83 in Michigan for soluble rock at the surface, and sits above 0% of US counties on that measure.