I-25 Rockfall Mitigation Raton Pass

Challenge

Interstate 25 runs north and south from El Paso, Texas, through Wyoming. Raton Pass, from Trinidad, Colorado to the New Mexico state line is notorious for rock falls. Sandstone rocks would break loose and fall when the underlying shale layers weathered and crumbled. It also required frequent clean-up efforts by the Colorado Department of Transportation.

Solution

The I-25 Raton Pass Rockfall Mitigation project consisted of rock scaling and rock excavation to create a stable rock face and a 30 ft. wide rockfall ditch to prevent fallen rocks from reaching the highway. The project constructed a stable, benched, 130 ft. high rock cut using controlled blasting methods for a length of 400 ft. Doweled and reinforced shotcrete facing was applied over the 2 shale layers for stabilization.

All traffic was removed from the adjacent North-bound I-25 lanes during construction for increased safety and production and to minimize traffic delays. The North-bound traffic was detoured to the South-bound lanes utilizing a two lane, two-way head-to-head configuration for a length of 7 miles. Throughout the project, the Rock Solid/CDOT Team worked closely together to minimize both the duration of the project and impacts to the traveling public.

Awards

• 2017 Statewide Joint CCA/CDOT Project Management Award (Safety Projects category) | Colorado DOT