Predicting Flash Flooding in Appalachia

On the night of July 24th, 2022, University of Kentucky Professor Chris Barton remembers not going to sleep. He was watching the weather radar on his television.

“And this system was coming up into, you know, over Pine Mountain and into this area, and it almost looked like a freight train. It just kept coming and coming. I kept watching it, and I just knew immediately, this is going to be catastrophic.”

It was horrific. About 16 inches of rain swamped 13 Eastern Kentucky counties killing 45 people and destroying 9,000 homes.

Barton is a U-K Professor of Forest Hydrology and Watershed Management. He says what happened in Eastern Kentucky is similar to the recent flooding disaster in North Carolina and Tennessee.

Barton says in both situations, extremely warm temperatures caused evaporation to hold massive amounts of water in the atmosphere.

“What happens is, when you have those extreme temperatures, one you get a lot of evaporation from, either the land surface or the water surface, as far as this year's event, and it holds that up into the atmosphere. And the atmosphere can actually hold more water when it's hotter. And in both instances, the same thing happened. Those atmospheric fronts moved northward and started to lift. And when they hit the mountainous regions of Kentucky in 2022 and North Carolina and Tennessee this year, the air lifts, it cools, and all that water is released. And unfortunately, the amount of water in those systems is just tremendous, and it overwhelms the system.”

To better understand and predict flash flooding in Appalachia, Barton is the principal investigator of a four-year, $1.1-million project that was just awarded by the U.S. National Science Foundation. It’s a collaborative effort by scientists and civil engineers from Kentucky universities including the University of Kentucky, Eastern Kentucky University, and West Virginia University.

Barton says learning how to better predict flash flooding in the mountains is a key part of the project.

“We have a plan to work with a lot of schools in the area and communities to educate people about the dangers of flash floods and how we can predict them, and then actually use technology in these communities to provide better early warning systems to become aware of when a flash flood is going to happen.”

To gather data about water flow in mountain streams the scientists will use Robinson Forest. The nearly 15,000-acre forest is in Breathitt, Perry, and Knott Counties.

100 years ago, a logging company owner named E.O. Robinson deeded the land in a trust to U-K. For decades scientists have used Robinson Forest for education and research.

As an example, Barton says since 1972 water quality and flow data has been collected at various streams in the forest. The streams have a small dam called a weir.

“We have a sensor in there that takes a measurement every 15 minutes, and we actually have a transmitter on this that uses a cell tower or uses a cell phone type of technology, and I can, in my office, actually go to this particular weir and see real-time data of the stream flow coming off of this site. Amazing. In addition, though, we've also collected a water quality sample here every week for over 50 years.”

Collecting water data in a controlled area like Robinson Forest, Barton says, will be invaluable for predicting what happens in the future. He says changes in the climate and weather patterns will lead to more problems with flash flooding.

“Because the temperatures are getting warmer. And as I said, with global heating, you're getting more evaporation and more water in the atmosphere and when it's hotter, it can hold more. We have about 1300 millimeters of rain every year, and we get about 100 millimeters every month. So that's a good amount of rain and it used to be, it would come, periodically, a little event here, then a few days later, an