Sinkhole risk in Windham County, VT: 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: 15%
At or near the surface: 0%
Buried under cover: 15%

The next step for one property

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

That works out to roughly 116 of Windham County's 786 square miles on soluble rock. With about 45,627 residents (58 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 300 map points about 1.6 miles apart, so a pocket smaller than that can be missed or overstated.

Worth reading for this county: why the 15% under cover still counts, and how these percentages are measured.

Counties around Windham County

The nearest county rated sinkhole country is Union County, PA, about 263 miles southwest. 5 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Bennington County, VT 20 mi west · 0% at surface
Cheshire County, NH 24 mi east · 0% at surface
Franklin County, MA 29 mi south · 0% at surface
Sullivan County, NH 36 mi northeast · 0% at surface
Windsor County, VT 40 mi north · 0% at surface
Washington County, NY 42 mi northwest · 0% at surface

The rock underneath

The largest mapped soluble unit here is the Waits River Formation (limestone), Devonian in age, covering about 14% of the county. Next is the Fitch Formation (Upper Silurian; Pridolian and Ludlovian) at under 1%.

Against the rest of Vermont

Windham County ranks 13 of 14 in Vermont for soluble rock at the surface, and sits above 0% of US counties on that measure.