The Nevada Department of Transportation began a project Wednesday to reinforce a destabilized roadside slope on U.S. 50 at Lake Tahoe.
This year, numerous boulders roughly the size of large passenger vehicles have fallen from a slope onto eastbound travel lanes of U.S. 50 near Logan Creek Drive north of Cave Rock. No vehicles have been involved in the slides, and no injuries reported. Since then, travel lanes have been reduced to one lane in each direction, with both directions of traffic shifted to westbound lanes away from the rock fall area. NDOT placed rows of concrete barrier rail and large gravel bags on the closed eastbound side of the roadway to further diffuse and prevent rock fall onto travel lanes.
The project seeks to reinforce the slope, as well as construct a roadside wall to help prevent future erosion. Boulders and debris will first be cleaned from the bottom of the slope. Then, anchor bars drilled into the slope will secure heavy-duty mesh that will be covered with more than 16 inches of sprayable “shotcrete” concrete to create what is called a soil nail wall. The concrete will be hand-sculpted to match colors and textures of nearby natural roadside slopes. The wall will essentially stabilize the approximately 60-foot high slope by encasing it in concrete. Roadway surface and curbing damaged by the boulders will also be repaired.
U.S. 50 will continue to be reduced to one lane in each direction in the Logan Creek Drive area during construction. Brief travel delays may temporarily take place in future months if one-way traffic with pilot cars is needed to safely guide motorists through the road work zone during major construction activities.
Road and Highway Builders is the contractor for the approximately $5 million project. More than 13,000 motorists who drive the road daily. Construction is anticipated to be completed next spring, depending on weather and availability of specialized construction materials.
NDOT has dedicated approximately $15 million over past years to enhancing traffic safety by stabilizing roadside slopes to reduce rock slide and other erosion in U.S. 50 at Tahoe. The majority of U.S. 50 roadside slopes in the Glenbrook area have already been stabilized with rock fall netting or reinforced roadside slopes or have barrier rail/wall built at the bottom to contain and collect erosion-related rock fall. Last year, NDOT also extended the westbound, lakeside Cave Rock tunnel entrance to catch rock fall before it reaches the roadway.