Rock Falls I-70

CDOT workers tackle road damage from boulders. Photo courtesy CDOT’s Facebook page.

A 24-mile section of Interstate 70 in Colorado will be out of commission for weeks, Andrew McFarlane has reported for, because of car-sized boulders that slid onto the road earlier this week. It was a rock slide near Hanging Lake Tunnel in Glenwood Canyon (about 125 miles east of the Utah border) that caused the Colorado Department of Transportation to shut down the road from Exit 116 in Glenwood Springs to Exit 140 in Gypsum Monday night.

Although officials were expected to open a single lane yesterday (Thursday), traffic will be tied up while road crews work to remove the large boulders with a boulder buster, as CDOT calls the special equipment. The boulder buster is able to safely break up the large rocks using a high-impulse pressure waves. CDOT spokeswoman Tracy Truelove told Associated Press on Tuesday that the slope remained unstable, with a lot of loose rocks.

Determining Damage

The department wrote on the CDOT Facebook page that it has mobilized its Geohazards Team to determine what damage was done. The four-lane roadway ordinarily carries a daily average of 300 vehicles per hour, CDOT spokeswoman Amy Ford said.

Temperatures of nearly 50 degrees had contributed to a freeze-thaw cycle than can cause hillside rocks to tumble. There have been similar rockfalls in this area, in 2013 and 2010.

Alternate Routes

The Colorado State Patrol is advising drivers to use U.S. 40 or U.S. 50 while I-70 is narrowed down for boulder removal and road repairs. The detours will reroute drivers about 140 miles out of their way. quotes CDOT’s Ford on the detours: ”We encourage all options.” It could take drivers using the single-lane highway as much as two hours to make their way through the canyon otherwise.

No Accidents With Injuries

Fortunately, no injuries were reported due to the boulders falling onto the roadway. But there have been accidents. Truelove reports that in one incident, a truck hit a boulder the size of a small car after the car in front of the truck disappeared in a cloud of dust, according to the truck driver, Ray Hatch of Las Vegas.

CDOT wrote on its Facebook page:

CDOT crews and contracted rockfall workers will continue rock scaling at the location in an attempt to bring down any additional debris. As a safety precaution, crews will also install rockfall mitigation fence on the westbound lanes. On Thursday, a pilot car operation–directing single-lane, alternating traffic–will be implemented and traffic will be routed to the eastbound lanes. The pilot car operation could be in place for several days while early repairs and additional rock stabilization are completed. As repairs progress, we will open one lane in each direction. It could be several weeks before the damage to the roadway walls and roadway are repaired and the interstate is fully open. Check for updates and alternate route.

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