Environmental Geologist: Here’s What Might Have Happened With the Sinkhole at the National Corvette Museum

By Bradley Coyle - February 12, 2014

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[ Bradley Coyle (no relation to editor John Coyle) is an administrator for F150online. That’s right, the only geologist we know is a Ford guy. Insult and injury—we get it. But more appropriately, he has degrees in Hydrology and Environmental Geology. Even more appropriately, he’s a car enthusiast. After the sinkhole opened up this morning, we approached him for his opinion about the situation and what it might mean for the National Corvette Museum. His opinions about the geological situation in Bowling Green are his own. —Eds. ]

The Bowling Green, Kentucky area where the Corvette Museum is located sits in what is known as a karst area. This is an area where water slowly dissolves the native bedrock—usually limestone— in the subsurface. Once the bedrock is dissolved to a point, it is no longer structurally sound to support the weight of what is on top of it, it fails or collapses.

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“While it’s not uncommon for a sinkhole like this to open up in the area, it’s more likely to occur in an area of a vacant field or similar that has not been assessed for such features.”

Generally speaking, when a structure is erected in the Bowling Green area, geotechnical studies are performed to ensure that the bedrock in the area—which is normally located very near the surface—is structurally sound to support the weight of a building and the building’s contents. While it’s not uncommon for a sinkhole like this to open up in the area, it’s more likely to occur in an area of a vacant field or similar that has not been assessed for such features.

In my opinion, it’s highly unlikely that this sinkhole has formed since the construction of the building and was likely missed as part of the geotechnical survey of the area as these things just don’t happen over a short geologic period. Geologic time normally runs in tens of thousands of years, at a minimum. Unfortunately though, items like this can be missed due to their very specific area and geologic characteristics.

For example, this void that was beneath the building could have been missed by mere feet during the geotechnical survey because the rock immediately surrounding the failure could’ve been massive and very competent to support the building. While this is a large sink, the types of surveys performed to locate a building don’t typically involve large-scale rock coring to ensure structural competency due to the high cost associated with such assessments.

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As a hydrogeology student at Western Kentucky University located in Bowling Green, I can recall this type of a sinkhole occurring a couple of times over my years in college and my beginning years as a professional in the area. One of these sinks swallowed a very new road expansion a few years after it was completed.

That sink was likely three times the size of the one at the Corvette Museum. In similar fashion, the sinkhole was missed by geotechnical assessment and was located about 100 yards away from a large, newly constructed church which likely also had a geotechnical assessment prior to being built.

“The void which was beneath the Sky Dome could have been missed by mere feet during the geotechnical survey.”

I am glad that these weren’t Mustangs but, I am certain that F-150 owners in the area would be more than willing to come over and help pull out these Chevrolets.

In all seriousness—and as a Corvette enthusiast myself—it’s a real shame to see this level of American muscle swallowed by a fluke of nature.

As for the future of the Sky Dome, generally structural engineers are able to remedy sinks and allow something to be built upon them, but that involves a pricey—and long—process of building the hole back up. And obviously, it will not be able to take away the underground water which caused the problem.

As for Chevrolet’s intentions or worries, I certainly can’t comment. The entire area is only about 30 minutes away from Mammoth Cave National Park—the largest known cave system in the world—and a sinkhole and a cave in that area form in exactly the same fashion.

But the size and severity of the hole could potentially mean others might be present in the area, and warrant additional assessment around the museum grounds. If it is determined that this is a faulty drain or some other kind of man-made errosional feature, it’s unlikely that problems exist other than a significant design or build flaw.

Head to the forum to see what members are saying about the developments at the museum. >>

National Corvette Museum Building