SinkholeOdds

Sinkhole risk in Northwest Hills Planning Region, CT: 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
10%
At or near the surface
0%
Buried under cover
10%

What to do about a house in Northwest Hills Planning Region

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

That works out to roughly 79 of Northwest Hills Planning Region's 787 square miles on soluble rock. With about 114,101 residents (145 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 257 map points about 1.7 miles apart, so a pocket smaller than that can be missed or overstated.

Two things to read before deciding: why the 10% under cover still counts, and how these percentages are measured.

Counties around Northwest Hills Planning Region

The nearest county rated sinkhole country is Union County, PA, about 208 miles west. 3 of the 6 closest counties land in the same band; the ground changes quickly around here.

What Northwest Hills Planning Region is built on

The largest mapped soluble unit here is the Unit b [of Stockbridge Marble] (marble), Upper and Middle? Cambrian in age, covering about 4% of the county. Next is the Unit c [of Stockbridge Marble] at 4%.

Against the rest of Connecticut

Northwest Hills Planning Region ranks 6 of 9 in Connecticut for soluble rock at the surface, and sits above 0% of US counties on that measure.