Rock slide keeps highway closed |

Rock slide keeps highway closed

Staff report
Special to the Times/CDOT

A contractor for the Colorado Department of Transportation began work Monday to assess steep slopes above Highway 133 south of McClure Pass to determine if any rocks needs to be knocked off.

The rock scaling, as the work is called, could last into Wednesday, the agency said. Once it is determine that the slope is safe, crews will start blasting seven or eight large rocks that tumbled onto the highway near Paonia Reservoir.

A rock slide with a cumulative measurement of 120 feet long and 50 feet wide and 20 feet tall blanketed the road. The largest of the rocks were 30 feet long, 15 feet wide and 10 feet tall — about the size of a dump truck, CDOT said. The falling rocks gouged the highway. Crews will have to repair a depression two feet deep and about 12 feet long and 10 feet wide, CDOT said in a news release.

The rock slide occurred at about 9:30 a.m. Sunday morning at mile marker 29, about 13 miles south of McClure Pass. No injuries were reported. The road closure affects commuters between Paonia and Carbondale, Glenwood Springs and Aspen. Traffic is unimpeded within the Crystal River Valley.

Yenter Companies was hired to help CDOT rockfall specialists assess if the slopes are safe and to dislodge any rocks deemed to be a threat. Yenter crews will climb the hillside, anchored by safety ropes. They will use pry bars, when possible, to dislodge rocks. In other cases, air bags will be inserted behind rocks and inflated until the rock breaks free, according to CDOT.

Once the hillside is deemed safe, crews will blast rock on the highway and haul it away. “It is possible this could happen Wednesday or Thursday — all work is expected to last at least through this Friday,” CDOT’s statement said.

“The McClure site is ranked at the top of our Rockfall Hazard Rating System,” Ty Ortiz, CDOT rockfall specialist said in the statement. “The amount of rockfall we see here on an annual basis is quite a bit higher than what we see in many other sites around the state.”

That stretch of Highway 133 was hit with another massive rock slide on April 27, 2007. The May 5 incident brought rock down from further above the slide origin in 2007. Sandstone is plastered onto layers of shale, creating the recipe for large-scale slides.