Rock Scaling Work to Get Underway on US 550 Red Mtn. Pass

April 23, 2014 - Southwestern Colorado/CDOT Region 5 - Extended road closures Monday through Saturday likely through May.

OURAY/SAN JUAN COUNTIES – The Colorado Department of Transportation will begin a project to scale more rocks off the mountainside above US 550 on Red Mountain Pass, where a large rockslide event on January 12 led to a near month-long closure. Since the re-opening of the highway on February 10, traffic has been in a single-lane, alternating configuration 24/7, controlled by a signal.

CDOT will hire a contractor to conduct the follow-up scaling work, which will involve climbing to the rockfall site above US 550, removing and repairing the existing rock fence (which is anchored to concrete barrier on the roadway’s center line) and installing rockfall monitoring equipment.

This work is estimated to cost $928,000. Later this summer, CDOT will be contracting a project that will provide a longer-term mitigation solution for this area. That project will include the installation of additional mesh on the slope, as well as rockfall fences and rockfall attenuators. The final design will be dependent on the success of this rockfall scaling work and the information gathered during the scaling.

The Colorado Transportation Commission provided $173,588 in contingency funding for the design, while construction estimates for the summer mitigation project are totaling $2.3 million (estimates will change based on scaling work). Further details about the next phase of work will be sent at a later date.

TRAVEL IMPACTS: Starting Monday, April 28, and lasting for up to four weeks (ending prior to Memorial Day), US 550 on Red Mountain Pass will be FULLY CLOSED between Ironton Park (mile marker 87) and south of Ouray (MM 92) during these hours:  8:30 a.m. to 12:30 p.m. AND 1:30 p.m. to 6:30 p.m., Monday through Saturdays. The pass will be open all other times, with single-lane, alternating traffic controlled by a signal.

ALTERNATE ROUTE: The alternate routes are the following:  From Ouray to Durango (a distance of 70 miles using US 550) motorists will instead use SH 62 from Ridgway over Dallas Divide, SH 145 over Lizard Head Pass, then US 160, for a trip of 154 miles (an 88-mile detour). The average daily traffic count on Red Mountain Pass is 2,200.

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