UPDATE: At 4 a.m. on Sept. 12 the road reopened.
BOULDER COUNTY, Colo. (CBS4) – A major rockfall forced CO 119 in Boulder Canyon to close on Wednesday. The Colorado Department of Transportation says the rockfall came from a previously scheduled blast.
That blast was part of the CO 119 flood construction project which will move the roadway onto more bedrock to prevent possible erosion during a major flood.
(credit: Colorado Department of Transportation)
Crews say a typical blast sends about 400 cubic yards of rock down the canyon, but this blast caused about 8,000 cubic yards of rock to fall onto the road.
A major rockfall on Colorado Highway 119 in Boulder Canyon. (credit: CBS)
For reference, officials say a cubic yard is about the size of a washing machine.
No one was hurt.
(credit: CBS)
Some of the boulders were too big to move and will needed to be blasted themselves. Additionally, the blast caused other rock to be loosened.
(credit: CBS)
Officials with the Boulder Valley School District said they would send school buses to homes on the other side of the blast. Highway 72 is being used as a detour.