CDOT Video Highlights Rockfall Event, Risky Work on US 550 Red Mountain Pass

March 26, 2014 - Southwestern Colorado/CDOT Region 5 - Incident from 900 feet above kept Million Dollar Highway closed for nearly a month.

OURAY/SAN JUAN COUNTIES – “Rocks on Red Mountain Pass—An event that tested community, commitment and courage,” is the name of a new video produced in-house by the Colorado Department of Transportation and posted on YouTube at: US 550 was closed between Ouray and Silverton for nearly a month due to a large rockfall event on January 12, 2014 (the highway was officially closed from January 13 through February 10, but opening for traffic two times a day on January 31).

More than 40 CDOT crew members and some two dozen contracted staff were involved at various stages of the near month-long emergency mitigation project.

“I credit our team for having the foresight to bring in additional experts from our consulting team, as well as neighboring Ouray and Silverton communities to help us get our job done safely and effectively,” CDOT Region 5 Transportation Director Kerrie Neet said. “This truly was a community effort in every sense of the word.”

After a 15-foot slab the length of a football field came crashing down onto the slope 900 feet above the highway, smaller rocks continued to cascade down onto US 550. The rockfall project involved the following:

  • CDOT assessing the situation and mobilizing rockfall and maintenance crews and consultant Yeh & Associates;
  • Rock scaling by CDOT rockfall contractor Yenter Companies;
  • Mobilization of Rigging for Rescue, Ouray-based climbing experts, who set a ropes course around the rockfall area;
  • Transporting 32 rockfall netting panels (each 12’ wide by 72’ long) to the slope by Silverton Mountain’s helicopter;
  • Setting 600 feet of concrete barrier to separate traffic from a fence along the highway's centerline;
  • Constructing the 24-foot tall fence, built from remaining rockfall netting panels, would serve as a temporary safeguard until a spring project can provide a more permanent rockfall mitigation solution.

The contracted portion of the rockfall mitigation work cost an estimated $670,000.  On March 3, Governor Hickenlooper declared the work as a “disaster emergency,” which now enables CDOT to pursue federal transportation emergency relief funds. The Colorado Transportation Commission provided $173,588 in contingency funding for the design, while construction estimates for future mitigation are totaling $2.3 million.

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