DENVER (KDVR) — FOX31 looked into long-term solutions to stop the constant closures and rockslides on Interstate 70 in Glenwood Canyon.
A view from above Monday highlighted the extreme impact in Glenwood Canyon from debris flows that slammed into I-70. Drone video captured the area that saw 4 inches of rain in five days, nearly double the average monthly rainfall.
“It’s a tough situation. There’s not a lot of great options,” U.S. Geological Survey research hydrologist Jason Kean said.
Kean walked the FOX31 Problem Solvers through four ways engineers can try to mitigate these situations.
Debris flow nets
The first option is debris flow nets. Kean says they look like giant chain link fences, and they are popular in Europe.
“It is good at stopping the big stuff, the boulders, but it’s not as good as stopping the water, and we’ve got a lot of both in this situation,” Kean said.
A second option is something we see near Red Mountain Pass: avalanche sheds.
“They are made of concrete. It’s not unlike a road deck, and we’ve seen how much damage the debris flow did to the I-70 road deck. It would do similar damage to a shed,” Kean said.
A third option is deflecting berms, something the Colorado Department of Transportation created on Hanging Lake tunnel last year.
The berms are walls built up to deflect debris flows in different directions.
Debris catch basins
The fourth option is popular in Los Angeles: debris catch basins.
“It’s a giant hole in the ground to catch it. They are really effective at catching it, but there’s not enough room in the canyon to make one of those,” Kean said.
CDOT told FOX31 that engineers are exploring a debris basin around Exit 129 (Bair Ranch), where there have been very large volume slides, but a naturally flatter area near the roadway could be a good candidate for this type of solution.
“My hat’s off to those engineers that are going to solve the problem,” Kean said.
Outside of engineering solutions, the most important restoration will be letting Mother Nature run its course. Vegetation will gradually return. Unfortunately, Kean says this process can take between two and 10 years to recover.