September 8, 2016 - Southwestern Colorado/CDOT Region 5 - OURAY & SAN JUAN COUNTIES – The Colorado Department of Transportation (CDOT) and contractor Rock & Company are pleased to announce completion of crib wall work on US Highway 550 (US 550) Red Mountain Pass.

This two-season project, which began summer of 2015, improved the safety and integrity of the highway by reinforcing or replacing several under-highway downhill retaining walls.  This stretch of US 550 receives an average annual daily traffic count of more than 2000 vehicles a day.  The total cost of this project (from design through construction) was $5.9 million.

The project repaired or replaced retaining walls at three locations on US 550:

  • Site 1 MM 79.5 to MM 79.4 – Approx. 9 miles north of Silverton just south of Red Mt. Pass summit

Rock excavation and blasting for roadway widening, realignment and drainage improvement, culvert installation, replacement of three retaining walls, new guardrail installation and roadway reconstruction.  

  • Site 2 MM 88.5 to 88.6 – Approx. 4 miles south of Ouray near the snow shed

Excavation, culvert installation, replacement of three retaining walls, minor paving.

  • Site 3 MM 89.5 to MM 89.7 – Approx. 3 miles south of Ouray near the Ruby Walls

Excavation and roadway stabilization which included installation of a concrete “cap” or slab over the crib wall, retaining wall repair, drainage improvements and paving.

Scott Davis, Vice President of Rock and Company said, “The success of this project is a result of a strong relationship between CDOT, consultant project engineer (Yeh & Associates), and prime contractor Rock & Company. The project faced challenges including inclement weather, heavy traffic, limited space, high elevation, and high slopes. The work was technically difficult. Ultimately, it was the ability to quickly make decisions as a team that resulted in delivering this tricky project on time and within budget. We are very pleased with the added safety improvements and wider roadway.”

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(Top left photo) Crews use heavy equipment to guide a new beam into place which will ultimately strengthen the crib wall (retaining wall) underneath the highway.  (Top right photo) Road stabilization included the installation of a “cap” or layer of concrete to aid in erosion control.

US 550 Red Mtn. Pass crib wall project – finished product (below)