Serving Boone, Blowing Rock, Banner Elk, and other towns of the North Carolina High Country
Founded 05-05-05
January 11, 2007 issue
DOT Dismisses Rockslide Rumor
Story by Kathleen McFadden
NCDOT District Engineer Kipp Turner put the kibosh on a persistent rumor about the Highway 321 landslide that occurred in early December. The rumor has been circulating that residential construction work on the slope above the highway caused the slide.
“Not in our opinion,” Turner said. “DOT has never said that. I don’t know how you could tell for sure and there’s not enough there for me to speculate.”
Turner said that engineering and geotechnical examination of the slope showed deep cracks in the rock, freeze-thaw action and plenty of tree roots, all of which could have caused or contributed to the slope failure.
The rockslide that occurred midmorning on December 6 closed one lane of the highway, but did not result in any injury or property damage.
Turner said that the slide didn’t appear to be much of an issue at first. Trees at the base of the slope caught most of the debris and only a few rocks were in the road, so the engineers estimated that cleanup would take about a day and a half.
“But when the geotechnical people started scouring the area, they discovered that the slope was unstable,” Turner said. “It was in our best interest to take the slope down under our conditions,” he added.
At that point, the DOT revised the cleanup timeline, estimating that the project would extend into early January because of uncertainty about the slope composition, the necessity of blasting, the proximity of homes above and below the slope and an overhead power line.
However, NCDOT and contractor personnel worked long hours to clear the debris and stabilize the slope, and the work was complete by December 19.