GLENWOOD SPRINGS, Colo. (KDVR) — The Colorado Department of Transportation is warning drivers of potential safety closures involving mudslides on Interstate 70 through Glenwood Canyon. 

Firefighters continue battling the Grizzly Creek Fire, which closed the interstate for two weeks. 

Now, geologists are worried steep, rocky cliffs will be susceptible to mudslides. 

“There’s a lot of eyes on the situation,” says USGS Geologist Jason Kean. “The problem is, the trigger’s pretty low.”

Kean is a research geologist for USGS, which has been studying the burn area for areas of high concern. 

In certain areas, he says just 2/10th’s of an inch of rain could trigger significant slides. 

“It doesn’t take a particularly strong storm for that to happen,” says Kean. 

USGS has spent the past few days creating maps showing the likelihood and potential volume of debris flows, which have been sent to the U.S. Forestry Service and CDOT. 

“Those rainfall thresholds are really important, because the national weather service can use those to issue watches and warnings for the burn area,” says Kean. 

Friday night, CDOT was preparing for potential closures, with workers in place at mile markers 116 near Glenwood Springs, and 133 in Dotsero. 

“So we literally have people standing by, in the event we have to call for that closure,” says Elise Thatcher. 

Thatcher says if necessary, CDOT can evacuate the canyon in about an hour. 

“We’ve doubled the amount of time we think it will take to evacuate the canyon,” she says. “Just so we have extra room to work to make sure we can get everybody out in time.”
Thatcher says rest stops in the area are closed, as firefighters use them for overnight camp-sites. 

“There is absolutely no stopping in the canyon,” she says. “This means rest areas are closed, and as most folks know, there really is no room to pull over on the side of the canyon, and we would strongly ask that folks not try that.”