The Colorado Department of Transportation and contractor Tricon 2, LLC are resuming a project this week to mitigate a landslide area that has been impacting a section of U.S. 160 east of Pagosa Springs. The Jackson Mountain slide area lies five miles east of Pagosa, near milepoint 151.
The project is being conducted in two phases.
Phase 1 began in September 2010 and was completed in late fall. Work was suspended through the winter months, and this second and final phase will be completed by late November 2011.
The landslide, which has been monitored and studied over the years, is essentially bedrock sloping towards the river below — some 50 to 80 feet of earth atop this bedrock continues to slide with the great amount of surface — and groundwater in the area. The project to mitigate for future sliding and make repairs to the highway is being funded with $5.2 million in funding from the State Transportation Commission.
CDOT has been expending money to maintain this section of highway to keep it passable for years and noted that the slide area appeared to be worsening as time went by, and more rapidly in recent years. The State Transportation Commission thoroughly reviewed the details of this issue and determined immediate action was necessary.
“We are pleased to be entering into the final phase on this extensive reconstruction project,” State Transportation Commissioner Steve Parker said. “U.S. 160 is a vital corridor for commuters, tourism and commerce in southwest Colorado. This permanent fix has been needed for a long time.”
• Phase I (September through mid-November 2010). The work during this first phase involved installing a surface and underground drainage system (3-inch pipes) and installing 44 ground anchor tiebacks (steel cable systems) to stabilize the hillside below the highway.
• Phase II (April 2011 through late November 2011). The work will involve installing 44 additional ground anchor tiebacks to further stabilize the lower portion of the slope. A buttress at the toe of the slope (just above the river) will be constructed using a concrete base and 10,000 cubic yards of rip-rap, or specific rock material. (No work will be done at the riverside until after July 15 to avoid fish spawning.) Finally, crews will do a “deep-patch repair” and reinforce a 500-foot section of U.S. 160 that has been damaged over the years by the slide.
Work hours are Monday through Friday, from 7 a.m. to 7 p.m. At this time, limited weekend work and no holiday work is anticipated.
During project work hours, motorists will encounter minimal travel delays. All business and residential accesses will be maintained. During highway repairs in Phase II, travel will be more directly impacted; details will be sent at a later date.
CDOT and Tricon 2, LLC crews greatly appreciate your patience and cooperation while driving through the work zone. Thank you for going Slow for the Cone Zone!
Tricon 2 has a local project information hotline for public use; that number is 264-0542.