Limestone makes mid-Missouri sinkhole susceptible

Curtis Powelson fell down this sinkhole while deer hunting Monday night.

The rock composition of much land in mid-Missouri makes it prone to sinkholes.

When water flows through the porous limestone it erodes the rock, sometimes resulting in underground caverns.

"Eventually the rock over the top...the roof, if you will, of this cavern gets thinner and thinner. And at some point it's so thin that it won't hold itself up. And it sinks," University of Missouri professor emeritus Raymond Ethington said.

That's what happened in Pulaski County, and 31-year-old Curtis Powelson fell around 70 feet and died.

Ethington said sinkholes take thousands of years to form and are nearly impossible to detect from the surface. Still, the likelihood of one opening up under your feet is very slim.

If you're planning on building a home in sinkhole-prone area, you should hire someone to assess the ground underneath the surface first.

It may be expensive, Ethington says, but not as expensive as losing your home to a sinkhole.