SinkholeOdds

Sinkhole risk in Erie County, NY: 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
26%
At or near the surface
0%
Buried under cover
26%

What to do about a house in Erie County

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

That works out to roughly 266 of Erie County's 1,043 square miles on soluble rock. With about 950,602 residents (912 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 271 map points about 2.0 miles apart, so a pocket smaller than that can be missed or overstated.

Read next: why gypsum and salt move faster than limestone, and why the 26% under cover still counts.

Counties around Erie County

The nearest county rated sinkhole country is Union County, PA, about 152 miles southeast. 2 of the 6 closest counties land in the same band; the ground changes quickly around here.

What Erie County is built on

The largest mapped soluble unit here is the Camillus, Syracuse, and Vernon Formations (shale), Upper Silurian in age, covering about 16% of the county. Next is the Onondaga and Bois Blanc Limestones at 9%.

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 New York

Erie County ranks 19 of 62 in New York for soluble rock at the surface, and sits above 0% of US counties on that measure.