Both lanes of southbound Interstate 81 in Montgomery County near Blacksburg, Va., have been closed starting at mile marker 132 due to an unstable slope.
Traffic will be detoured at exit 132 (Dixie Caverns) onto Route 11/460 and back onto I-81 at exit 118 (Christiansburg). The detour will remain in place for at least one day but could remain as long as ten days. As a safety precaution, traffic will be detoured until the unstable material on the slope can be brought down. It is unknown at this time exactly how long it will take to stabilize the slope.
Crews have been blasting as part of work to repair an unstable slope near mile marker 124 on a project to construct a truck climbing lane in Montgomery County between mile markers 120 and 125. During a scheduled blast on Monday, Aug. 26, an existing crack in the unstable slope increased from approximately 50 feet to 120 feet in length. Geotechnical specialists have spent today reviewing the slope, and VDOT in the interest of public safety has decided to close southbound Interstate 81.
The next blast is scheduled for today (Wednesday). Once this blast is complete, a more definite time frame for how long the detour will be in place may be available.
During the blast on Wednesday, Aug. 28, State Police will slow traffic on northbound I-81 beginning at mile marker 114 to keep the area near the blast clear of traffic. Once the blast has occurred, traffic will be released to travel at a normal speed. Drivers should expect delays. During blasting, the on-ramps will be restricted onto northbound Interstate 81 at exit 118 (Christiansburg). Flaggers will control traffic on Route 636 (Seneca Hollow Road and Friendship Road) during blasting.
Signs and message boards will be in place to alert drivers.
Work on the truck climbing lane project is expected to be completed in November 2013. For traffic information and updates, visit www.511Virginia.org.