CHARLOTTE — They can be common in the Blue Ridge area during big storms like Thursday’s, but geologists have spent years mapping out where the risk is highest for landslides.
In the Blue Ridge Mountains, Davidson College Professor Brad Johnson says you don’t have to look too hard for evidence of landslides.
“This whole thing liquified and then blobbed out into the bottom here,” Johnson told Channel 9 Climate Reporter Michelle Alfini.
Usually triggered by heavy rain, often from tropical systems, landslides occur when the soil is so saturated that it starts to flow downhill, taking anything in its way with it.
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Johnson says the Blue Ridge has seen thousands over the past century.
“Now we have thousands of people, we have all this development, so people are in the line of fire in a way that they weren’t historically,” Johnson said.
One of North Carolina’s worst landslides happened 20 years ago in Macon County after the remnants of Hurricane Ivan moved through. Five people died.
“There’s not a lot of warning and there’s not a lot to do,” Johnson said.
He says that while there’s no way to predict an imminent landslide, the biggest indicator of a future landslide is one that has already happened.
“If you’re living on old landslide debris, it’s probably a concerning place to be in one of these storms,” Johnson said.
That’s why state geologists have been mapping landslide sites and asking developers to avoid those areas.
But where it’s already happened, people like Watauga County Emergency Services Director Will Holt say they try to give as much warning as they can.
“We make sure our equipment is ready, we get messaging out to the public if we think there are areas that are more prone to that than others,” Holt said.
Johnson says the risk is high whenever the mountains see more than five inches of rain. We’re expecting to see at least double that with Thursday’s weather before Hurricane Helene moves into the area. Holt is asking everyone in the mountains to avoid travel and report serious flooding immediately.
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“Staying off the roads is the biggest thing you can do to help us out,” Holt said.
Johnson recommends anyone who lives on a steep hillside to seek a hotel or another place to spend the night until the storm is over.
While it’s difficult to predict where it’ll happen, landslides somewhere in the Blue Ridge this weekend are a near certainty.
You can see a map of the western North Carolina landslide spots by clicking this link.
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