Southeastern Section–56th Annual Meeting (29–30 March 2007)

Paper No. 3
Presentation Time: 8:40 AM


WITT, Anne C.1, SMITH, Michael S.2, LATHAM, Rebecca S.1, DOUGLAS, Thomas J.1, GILLON, Kenneth A.1, FUEMMELER, Stephen J.1, BAUER, Jennifer B.1 and WOOTEN, Richard M.1, (1)North Carolina Geological Survey, 2090 U.S. Highway 70, Swannanoa, NC 28778, (2)Geography and Geology, University of North Carolina Wilmington, 601 S. College Rd, Wilmington, NC 28403,

In August 1940, the southeastern United States experienced two major flood events. The larger of these events, the remnants of an unnamed Atlantic hurricane, affected portions of northwestern North Carolina and eastern Tennessee between August 13th and 14th. Aerial photography interpretation and fieldwork completed by the North Carolina Geological Survey documents at least 600 debris flows and slides occurring in the southeastern portion of Watauga County during this storm. Newly acquired 1940 aerial photography indicates that approximately 100 to 200 more debris flows occurred in central and southern Watauga County. The greatest concentration of debris flows occurred along the Blue Ridge Escarpment; primarily the Elk Creek reentrant in southeastern Watauga County.

Landslides claimed twelve lives, nine of those in the Stony Fork Township near Deep Gap in eastern Watauga County. Rainfall amounts were high in the area, generally ranging from 12 to 13 inches for the week, with the highest intensity rainfall occurring on the evening of August 13th. Flooding and mass movements effectively cut off major portions of the county for over two weeks. Debris flows and flooding severed a 6-mile section of U.S. 421 in 21 places between Deep Gap and Maple Springs in Wilkes County. Washouts and landslides also dissected the nascent Blue Ridge Parkway. In neighboring Caldwell County, flooding destroyed 90% of the bridges and mass movements closed many of the roads leading into Watauga County. Rescue, recovery, and relief operations for victims of the debris flows and flooding in the region were stymied and rescuers resorted to crossing difficult terrain on foot and by horse.

At that time, Watauga County was sparsely populated and largely agricultural; the U.S. Census Bureau reports 18,114 people living in the county in 1940. By 2000, the population had more than doubled (42,695), with most of the growth occurring in the last 30 years. Many areas shown on the 1940 aerial photography inundated by mass movements have since been developed due to the rapid increase in urban (~13%) and rural populations (~30%) since the 1970's. Another storm of similar magnitude would likely cause significant damage to lives, property and transportation corridors without careful land use evaluation and planning.