CDOT work to mitigate rockfall risk on CO 133 McClure Pass completed on schedule

Travel Advisory

November 15, 2021 - Northwestern Colorado

GUNNISON & PITKIN COUNTIES — The Colorado Department of Transportation and contractor Geovert have completed the project to mitigate the risk of rockfall along Colorado Highway 133 between the McClure Pass summit and Carbondale. The work, which began on April 19, had an anticipated project completion date of late October, which was met. Crews reset barriers and removed work equipment and materials in early November. All project activities are now finished.

The project involved five separate work areas on the north side of the pass. Work included rock scaling (bringing loose surface material down with pry bars or other equipment) and stabilization; rock excavation and blasting; rockfall wire mesh installation; and construction of a rockfall catchment structure. Click here to view video of successful rockfall blasting and scaling on the project in September.

The following rockfall mitigation work was completed:

  • Firehouse, MP 52.6 - Work involved rock scaling (bringing loose material down with pry bars and other equipment), additional excavation with a hammer excavator, and draped mesh.
  • Gray Cut MP 60.20 / Nettles MP 60.3 - These adjacent sites received the same mitigation treatment as the Firehouse site, above. The Nettles site included 15-foot-long rock dowels and a reinforced shotcrete (sprayed concrete) buttress to retain a large boulder.
  • Penny Hot Springs MP 55.2 - Mitigation at this site required crews to build a gravity wall, a concrete-faced, gravel rock-filled wall, approximately 21-feet tall, 12-feet thick and 425-feet long, to contain rockfall material.
  • Hunter’s Loop Cut, MP 48 - This site required blasting of rock material; the work involved drilling into rock, initially, followed by a few periods of midday blasting. The hillside was further stabilized with the installation of 25-foot-long rock bolts, heavy-gauge cable mesh and a lighter-gauge draped mesh (hung with the use of a crane).
  • Placita Disposal Site, MP 47.1 - This area was re-graded.
  • This project also included erosion control and localized highway repair at each of the five sites between Mile Points 48 and 60 (for reference, the south edge of Carbondale is at approximately MP 67). Crews also graded the Placita rock disposal site near the northern base of the pass (MP 47).

Continued CDOT Maintenance Work

  • Through November and possibly into December—until winter weather arrives—CDOT maintenance crews will continue to clear debris from past mudslides along the CO 133 McClure pass corridor. Motorists may encounter short sections of single-lane closures, resulting in minor travel impacts.

CO 133 McClure Pass Map

McClure Pass Rockfall

Project Information

For additional information about this project: