CDOT work to mitigate rockfall risk on US 550 Coal Bank Pass scheduled to begin May 12

Travel Advisory

May 8, 2025 - Southwestern Colorado - Traffic signals will be in place 24/7 with single lane alternating traffic between Durango and Silverton
Rockfall mitigation work will take place this summer at two locations along US 550 Coal Bank Pass, including stabilization and installation of a permanent rockfall catchment barrier near the Deer Creek Trailhead, MP 59.3
Rockfall mitigation work will take place this summer at two locations along US 550 Coal Bank Pass, including stabilization and installation of a permanent rockfall catchment barrier near the Deer Creek Trailhead, MP 59.3 .

Southwest Colorado — The Colorado Department of Transportation and contract partner Myers & Sons Construction will begin work to stabilize the rock face above US Highway 550 between Durango and Silverton starting Monday, May 12. Rockfall mitigation work will take place along Coal Bank Pass (Mile Points 56 to 60), approximately 11 miles south of Silverton and seven miles north of Purgatory Ski Resort. Motorists should plan for full stops and up to 20-minute delays throughout the duration of the project. Work is expected to be completed before this winter.

Temporary traffic signals will be in place 24/7 at two separate work locations, including:

  • Coal Bank Pass wall replacement (Mile Point 56.9), north of Engineer Mountain Trailhead
  • Deer Creek rockfall stabilization (Mile Point 59.3), Deer Creek Trailhead, south of Lime Creek Road (County Road 1)

The purpose of this project is to replace a wall structure north of Coal Bank Pass Summit and improve the stability of the existing slope at Deer Creek. Work will include scaling, stabilization and excavation operations. Material excavated from both sites will be stockpiled at a pull-out near Andrews Lake (MP 62.7), and travelers will encounter trucks turning at that location. After slope work is completed at Deer Creek, a permanent rockfall catchment barrier will be constructed.

“US 550 along Coal Bank and Molas Pass serves as an important connection to vital services for the community of Silverton. It is also a popular route for visitors, offering many year-round opportunities for recreation and sightseeing,” said Julie Constan, CDOT Regional Transportation Director. “This project is necessary to protect the safety of motorists and to prevent road damage or unexpected closures that would be caused by a natural rockslide.”

Deer Creek Trail access and parking will be maintained to allow hikers to continue to use the trail. All trail users are encouraged to use the designated parking area at the trailhead.

Travelers should not stop or park within any marked construction zones or staging areas.

Map of US 550 Wall Replacement project highlighting the three locations, including wall replacement (MP 56.9), rockfall mitigation (MP 59.3) and stockpiling (MP 62.7)
Colorado Department of Transportation project map of rockfall mitigation, wall replacement and stockpiling locations on US 550 between Coal Bank Pass and Silverton.


Traffic Impacts

Beginning May 12, work hours will range from 7 a.m. to 7 p.m., Monday through Friday with some Saturday work. Traffic impacts will include:

  • Between MP 60 and MP 56 traffic can expect to see two sets of traffic signals directing them to single lane alternating traffic through the work zones, 24/7 throughout the duration of the project
  • Motorists can expect intermittent delays with traffic holds up to 20 minutes at the Deer Creek location
  • Flaggers will guide motorists during daylight hours while work is occurring
  • Speeds will be reduced to 25 MPH through the work zone and traffic fines will be doubled
  • Lane widths through the work zones will be reduced to 11 feet throughout the duration of the project
  • Motorists should slow down as they approach the work zone, drive with caution, allow extra space between vehicles and give themselves extra travel time

Project Information

For additional information about this project:

Know Before You Go

Travelers are urged to “know before you go.” Gather information about weather forecasts and anticipated travel impacts and current road conditions prior to hitting the road. CDOT resources include:

Remember: Slow For The Cone Zone

The following tips are to help you stay safe while traveling through maintenance and construction work zones.

  • Do not speed in work zones. Obey the posted speed limits.
  • Stay Alert! Expect the unexpected.
  • Watch for workers. Drive with caution.
  • Don't change lanes unnecessarily.
  • Avoid using mobile devices such as phones while driving in work zones.
  • Turn on headlights so that workers and other drivers can see you.
  • Be especially alert at night while driving in work zones.
  • Expect delays, especially during peak travel times.
  • Allow ample space between you and the car in front of you.
  • Anticipate lane shifts and merge when directed to do so.
  • Be patient!

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