GeoStabilization's crews restore access after boulders destroy Highway 145

GeoStabilization International (GSI) was recently called upon to help reopen Highway 145 between Dolores and Telluride, Colorado, USA after a large-scale rockfall event destroyed a full-width section of the road.
GeoStabilization's crews restore access after boulders destroy Highway 145 GeoStabilization's crews restore access after boulders destroy Highway 145 GeoStabilization's crews restore access after boulders destroy Highway 145 GeoStabilization's crews restore access after boulders destroy Highway 145 GeoStabilization's crews restore access after boulders destroy Highway 145

GeoStabilization International was called upon when a rockfall blocked Highway 145 in Colorado, USA

The rockfall left an 8ft deep trench across both lanes and debris which included two large boulders weighing an estimated 2.3 million pounds and 8.5 million pounds, respectively. The event impacted about 150-200 linear feet of roadway, damaged power lines and fencing, and caused minor damage to a vehicle.

The Colorado Department of Transportation (CDOT) was first on the scene to evaluate the damage and determine a course of action. Because the origin of the rockfall was 1,800 slope feet above the roadway, CDOT deployed a drone from Aerial Applications Colorado to gather information for the mitigation efforts.

CDOT notified GSI of the event shortly after it occurred, and the GSI team started mobilising to the site. Working directly with CDOT's Geohazards Program representatives and engineers from Yeh and Associates, the team assessed the situation and developed a mitigation plan that included rock scaling and boulder downsizing in order to safely reopen the highway.

By the following evening, GSI's Rockfall Remediation Technicians (ferried to the upper slopes by Mountain Blade Runner Helicopter) had completed safety scaling from the source location 1,000 vertical feet above the highway down to the roadway surface along the "runout path" the boulders had created as they rolled down the slope.

The following day, GSI and Bedroc Blasting, Inc. from Cortez, Colorado downsized the smaller of the two boulders using controlled blasting. The larger of the two boulders will remain intact at the side of the road. Williams Construction, Inc. mobilised excavators, a hydraulic hammer, and a large loader to further downsize and remove the rock fragments. CDOT Region 5 Maintenance forces played a critical role in the overall operation and were responsible for creating temporary lanes to reopen traffic to Highway 145 only three days after the rockfall occurred.

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