A rock slide Sunday that closed Tennessee Route 108 between Viola and Altamont in Grundy County won't affect a lot of motorists. It is not a heavily traveled road, but closure still will inconvenience residents accustomed to using the highway. The closure also is a powerful reminder that rock slides are always a possibility in the region's mountainous terrain, and that commuters and travelers, in a very real sense, use the roads at their own risk.
True, the risk is small. No one was hurt in the Grundy County slide that brought down an estimated 23,000 tons of rock. No one was hurt, either, in recent slides on Signal and Lookout mountains in Hamilton County, on U.S. Highway 64 in Polk County and on Interstate 40 at the Tennessee-North Carolina border. Still, the possibility that someone will be injured or killed when falling rock slides onto a state road remains a scary possibility.
The Tennessee Department of Transportation works to minimize that risk. It uses a Rockfall Mitigation Program to identify potential rockfall sites and then assigns a hazard rating to each location. Currently, TDOT geologists and engineers have identified 232 priority sites and 949 "A" sites, including several in the tri-state region, that could provide a significant risk of a rockfall. To date, TDOT has lessened the danger at 33 of those sites. Clearly, the possibility of additional rock slides remains high.
Jennifer Flynn, spokeswoman for TDOT, said the Highway 108 cleanup should take about three weeks. The arduous job started Monday. Some of the rock can be removed with relative ease. The larger chunks- one is estimated to weigh 2,000 tons- will require crews "to drill and blast some rocks multiple times before they can be moved."
Until the work is completed and Route 108 reopened, those who used it regularly will have to take time-consuming detours. A spokesman for the Grundy County Sheriff's Office said that Highways 56 and 50 are options, but both "are steep, mountainous roads." Depending on point of departure and destination, he said either could easily add 25 minutes or more each way for those forced to use them.
It is difficult for experts to say precisely what caused the Grundy County rock slide, but whatever the reason the event should remind all who travel the state's hilly and mountainous roads to heed roadside signs that urge them to "beware of falling rock."