Sinkhole risk in Hillsborough County, NH: No soluble rock mapped

No soluble rock mapped

No soluble bedrock mapped.

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

What to do about a house in Hillsborough County

No soluble bedrock is mapped here, so natural sinkholes are unlikely. Collapses from broken pipes or old mines are a separate risk.

Across 877 square miles, under one square mile of Hillsborough County maps onto soluble rock. With about 430,462 residents (491 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 248 map points about 1.9 miles apart, so a pocket smaller than that can be missed or overstated.

Counties around Hillsborough County

The nearest county rated sinkhole country is Union County, PA, about 305 miles southwest. 5 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Cheshire County, NH 27 mi west · 0% at surface
Merrimack County, NH 27 mi north · 0% at surface
Rockingham County, NH 32 mi east · 0% at surface
Middlesex County, MA 34 mi southeast · 0% at surface
Sullivan County, NH 40 mi northwest · 0% at surface
Worcester County, MA 43 mi south · 0% at surface

Against the rest of New Hampshire

Hillsborough County ranks 6 of 10 in New Hampshire for soluble rock at the surface, and sits above 0% of US counties on that measure.