Heavy rains might have caused various sinkholes in Bowling Green, including this week’s collapse that claimed eight cars at the National Corvette Museum, but experts say it’s hard to know for sure.
“There’s really not any sort of predictability on sinkhole collapse,” said Josh Durkee, associate professor of meteorology at Western Kentucky University. “It’s plausible that these two are connected, but we can’t say at this moment.”
Sinkholes all over the region could be connected to weather and climate in the way the rocks are eroded and the way that limestone dissolves in water, Durkee said.
Wednesday’s museum sinkhole incident “happened not long after a heavy rain episode. By Feb. 4, we had had 3 inches of rain,” Durkee said. “Since that time, it has gotten really cold. A lot of water storage went frozen at that time, then the water storage thawed.”
Kevin Deitsch, a National Weather Service meteorologist, said the Bowling Green area has had 5.93 inches of rain since January, which is slightly higher than the average 5.49 inches. “Last year, (the amount of rainfall) was above that,” he said. “It was 6.27 (inches) this time last year.”
There also has been 4.1 inches of snow since January, bringing more moisture. The rainfall isn’t over yet. The weather service predicts a system coming Monday night into Tuesday and another Thursday.
Sinkholes are a natural feature of karst geology.
“The soil becomes weaker and collapses in the voids below it,” said Jason Polk, professor of geography and geology at WKU. “All of southcentral Kentucky is karst.”
Water can either cause or prevent a sinkhole, Polk said.
“When you have a lot of rain, it can cause a sinkhole formation to occur. It can take thousands of years or decades. As the water moves, it can make the soil heavy. It adds weight, and it may not be strong enough to hold it,” he said. “Another factor is when voids of water are underground. It’s void, but it still has water. If there’s a drought, it could remove the water and that causes the support to leave and causes collapse.”
Bowling Green has developed othersmaller sinkholes this week. Bowling Green public works began working to repair one on Cave Mill Road near Smallhouse Road on Thursday.
The westbound turn lane on Cave Mill Road near Smallhouse Road will be closed through Monday.
“Once we’ve got it excavated, we’ll come back to it,” he said. “We shouldn’t take long (to repair it), but we don’t want to put a date on it right now.”
Two minor sinkholes were at the Bowling Green Parks and Recreation Department’s Lovers Lane Park near the soccer fields.
“We’ve already put minor rocks in and put topsoil over it. We put caution tape around it until Monday or so. We’ll let it settle for a bit to make sure we don’t have any more sink,” said Brent Belcher, director of Bowling Green Parks and Recreation. “There’s not anything on the field itself. It took one day’s time. We played on it (Wednesday).”
While Mammoth Cave National Park hasn’t had a sinkhole, there is a mud-mire along the 6.2-mile Raymer Hollow Trail, causing it and the Raymer Hollow backcountry campsite to be closed. Other trails and campsites are available.
“It gets a lot of use. This location is such that we can’t do an easy reroute on it. There’s a lot of brush on either side,” said Vickie Carson, public information officer for the park. “The way the terrain is, we can’t say we can move the trail. The weather has kept us from going back there to look at it, and we’re short-staffed right now. There’s nothing else to do except close the trail until we can get our folks out there to assess the situation and decide what the next course will be.”
Some horsemen identified a “mud hole” where their horses sank up to their bellies, park Superintendent Sarah Craighead said in a news release.
“There’s a wet weather spring, so that causes some moisture, and there’s just a lot of hiking and horse use. It’s horrible for the natural resources there as well. It causes damage to the area around the trail,” Carson said. “We had some reports that people had had some real trouble getting through that area. It’s a terrible safety hazard. That’s why we had to close it.”
— For more information about karst terrain in Bowling Green, visit www.underbgky.org.