ST. LOUIS (KMOX) – Are more sinkholes forming or are we simply hearing more about them than we did in the past?
A Missouri University of Science and Technology geological engineer says about 25 percent of the United States has sinkholes and in Missouri the problem is compounded by the Mississippi River and its tributaries.
Dr. J. David Rogers says the phenomenon is nothing new and can be traced back to the Paleozoic Era, beginning roughly 541 million years ago.
“Their system of caverns has nothing remotely to do with the present typography so you can get them occurring right on top of the ridge and not always down in the bottom of the valley where the water goes to,” he explains.
Rivers in the area cause seepage which, over time, erodes the soil underneath the St. Louis area.
“You tend to get more underground erosion, which you can’t see. You can’t see it. You can be standing right over it, you can be living right over it. You can’t see that kind of thing but it’s occurring at some depth,” Rogers said.
Rogers says our proximity to the New Madrid Fault is unrelated to the number of sinkholes, though a strong earthquake can force worsening sinkholes to collapse.
But sSince scientists know seepage is occurring, can a sinkhole be predicted or prevented?
“When we’re putting in any kind of high-cost development, they go out and do geophysical surveys to see what anomalies they have out there,” Rogers said. “A sinkhole that is up near the surface, a filled one, will give a geophysical anomaly. You have to be looking for it and then you can confirm that by drilling or doing other geophysical test.”