Sinkhole risk in Grant County, NM: 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: 2%
At or near the surface: 2%
Buried under cover: 0%

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 59 of Grant County's 3,961 square miles on soluble rock, 59 of them with the rock at or near the surface. With about 27,541 residents (7 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 527 map points about 2.7 miles apart, so a pocket smaller than that can be missed or overstated.

Worth reading for this county: how these percentages are measured, and the warning signs that apply anywhere.

Counties around Grant County

The nearest county rated sinkhole country is Eddy County, NM, about 238 miles east. 3 of the 6 closest counties land in the same band; the ground changes quickly around here.

Luna County, NM 53 mi southeast · under 1% at surface
Greenlee County, AZ 61 mi northwest · 2% at surface
Hidalgo County, NM 62 mi south · 2% at surface
Sierra County, NM 74 mi east · 16% at surface
Catron County, NM 81 mi north · 1% at surface
Graham County, AZ 88 mi west · under 1% at surface

The rock underneath

The largest mapped soluble unit here is the Permain and Pennsylvanian rocks, undivided (medium-grained mixed clastic), Permain and Pennsylvanian in age, covering about 1% of the county. Next is the Lower Cretaceous, unidivided at under 1%.

Against the rest of New Mexico

Grant County ranks 27 of 33 in New Mexico for soluble rock at the surface, and sits above 56% of US counties on that measure.