Sinkhole risk in Mercer County, ND: No soluble rock mapped

What to do about a house in Mercer County

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

Across 1,043 square miles, under one square mile of Mercer County maps onto soluble rock. With about 8,348 residents (8 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 245 map points about 2.1 miles apart, so a pocket smaller than that can be missed or overstated.

Two things to read before deciding: why gypsum and salt move faster than limestone, and how these percentages are measured.

Counties around Mercer County

The nearest county rated sinkhole country is Fall River County, SD, about 294 miles south. 5 of the 6 closest counties land in the same band, so this is a regional pattern rather than a local quirk.

• Oliver County, ND 26 mi southeast · 0% at surface
• McLean County, ND 31 mi northeast · 0% at surface
• Dunn County, ND 37 mi west · under 1% at surface
• Morton County, ND 48 mi southeast · 0% at surface
• Stark County, ND 52 mi southwest · 0% at surface
• Ward County, ND 64 mi north · 0% at surface

Against the rest of North Dakota

Mercer County ranks 32 of 53 in North Dakota for soluble rock at the surface, and sits above 0% of US counties on that measure.

• Cavalier County 2%
• Ransom County under 1%
• Dunn County under 1%
• Barnes County under 1%
• Slope County under 1%