BOULDER COUNTY, Colo. — On Wednesday, the Colorado Department of Transportation said Colorado Highway 119 in Boulder Canyon would be closed for at least two days because of rockfall due to blasting.
On Thursday morning around 4:20 a.m., CDOT sent out a tweet saying Boulder Canyon reopened following the rock slide cleanup.
The blasting was part of the highway’s flood construction project. It is being done to move the road farther onto bedrock so it will survive another major flood.
Blasting typically brings down about 400 cubic yards of rock, but a blast Wednesday sent about 8,000 cubic yards of rock down the side of the mountain and onto the road.
A cubic yard is about the size of a washing machine, according to CDOT.
“You’re dealing with Mother Nature,” CDOT’s Jared Fiel said. “This is not an exact science.”
Fiel said CDOT is now investigating what caused more rocks to fall than planned.
“There are some theories right now…that because of rain and everything, that water may have expanded and made this worse. We don’t really know yet.”
The closure is expected to last two or three days, CDOT said.
No injuries were reported.