The Colorado Department of Transportation partially opened Interstate 70 through Glenwood Canyon Sunday evening, though drivers should expect delays of an hour or more.
The highway department will now alternate east-west traffic for part of the day. It's been closed since a huge rock fall a week ago.
CDOT spokeswoman Amy Ford says this event is one of the largest and most impactful rock fall closures the department has ever dealt with on I-70.
“In total, we’ve brought down approximately 400 tons of rock," Ford said. "Our crews have literally been working as quickly and as fast as they can to try to reopen the road."
A pilot car will lead vehicles east and then west along the 25-mile stretch of the interstate affected by the closure after 4 p.m. each afternoon. The highway will close each morning at 9 a.m. for additional rock fall mitigation and repairs to the roadway.
"This is treacherous work and we wanted to make sure that we opened the road under the safest conditions possible," Ford said.
Three boulders in the two to five ton range were brought down on Sunday.
On any given day, around 300 vehicles an hour pass through Glenwood Canyon. CDOT says the cost of repairing the main traffic artery through the state will be released when more in known.