Sinkhole risk in McKinley 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: 13%
At or near the surface: 13%
Buried under cover: 0%

What this means before you buy

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

That works out to roughly 720 of McKinley County's 5,451 square miles on soluble rock, 720 of them with the rock at or near the surface. With about 68,945 residents (13 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 303 map points about 4.2 miles apart, so a pocket smaller than that can be missed or overstated.

Counties around McKinley County

The nearest county rated sinkhole country is Emery County, UT, about 273 miles northwest. 4 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

Cibola County, NM 48 mi south · 29% at surface
San Juan County, NM 64 mi north · 3% at surface
Apache County, AZ 71 mi west · 10% at surface
Sandoval County, NM 77 mi east · 18% at surface
Bernalillo County, NM 97 mi east · 6% at surface
Valencia County, NM 101 mi southeast · 13% at surface

What McKinley County is built on

The largest mapped soluble unit here is the Chinle Group (medium-grained mixed clastic), Triassic in age, covering about 9% of the county. Next is the San Rafael Group at 2%.

11% of the county sits on gypsum or salt, which dissolves in years rather than millennia. That share matters more than its size suggests.

Against the rest of New Mexico

McKinley County ranks 17 of 33 in New Mexico for soluble rock at the surface, and sits above 70% of US counties on that measure.