Fort Fisher, NC Past and Present: A Geospatial Analysis using LiDAR and GIS

Abstract

Fort Fisher was constructed in 1861–1863 by the Confederacy at the mouth of the Cape Fear River in North Carolina to protect the vital trading routes of the seaport at Wilmington. The largest Confederate fort, Ft. Fisher was constructed as an L-shaped fortification consisting of 30 ft (9 m) thick earthen mounds capable of absorbing the shock of a heavy bombardment. In its prime, this fortification consisted of an approximately 1800 ft (550 m) long land face and a mile-long (1.6 km) sea face bounded by two larger 45 ft (14 m) and 60 ft (18 m) high mounds on the southern end. Today, Ft. Fisher is a mere remnant of its former self, with only about one-tenth of the original structure remaining. The region where the fort was constructed is a highly dynamic section of coastline that has undergone extensive shoreline retreat over the past century, resulting in the loss of the majority of the original fortification. Light detection and ranging (LiDAR) survey data and historical maps were used to generate past and present 3-D digital elevation models (DEMs) for both the terrain and fort. The historical shorelines, aerial imagery, bathymetric data and fort models were then integrated and compared within a geographic information system (GIS) to analyze and to model the evolution of the coastline from past to present. Results provide insight into the geographic advantages behind Ft. Fisher’s original layout for defense of the inlet compared to the present day geomorphology of the region.