SinkholeOdds

Sinkhole risk in Manistee County, MI: 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
1%
At or near the surface
0%
Buried under cover
1%

What to do about a house in Manistee County

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

That works out to roughly 7 of Manistee County's 542 square miles on soluble rock. With about 25,519 residents (47 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 329 map points about 1.3 miles apart, so a pocket smaller than that can be missed or overstated.

Read next: why gypsum and salt move faster than limestone, and how these percentages are measured.

Counties around Manistee County

The nearest county rated sinkhole country is Lake County, MI, about 31 miles southeast, close enough that the same rock may run under the county line. 3 of the 6 closest counties land in the same band; the ground changes quickly around here.

What Manistee County is built on

The largest mapped soluble unit here is the Michigan Formation (black shale), Mississippian in age, covering about 1% of the county.

1% 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

Manistee County ranks 56 of 83 in Michigan for soluble rock at the surface, and sits above 0% of US counties on that measure.