Vulnerability Indicators for Coastal Roadways Based on Barrier Island Morphology and Shoreline Change Predictions

• Published in: Natural hazards review 2021-05, Vol.22 (2)
• Main Authors: Velasquez-Montoya, Liliana, Sciaudone, Elizabeth J, Smyre, Elizabeth, Overton, Margery F
• Format: Article
• Language: English
• Subjects: Barrier islands; Brackishwater environment; Coastal morphology; Coastal zone; Coasts; Critical infrastructure; Dunes; Estuaries; Flooding; Forestry; Highways; Hurricanes; Indicators; Infrastructure; Islands; Lagoons; Marshes; Morphology; Oceans; Overwash; Regions; Remote sensing; Roads; Roads & highways; Sea fronts; Shoreline changes; Shorelines; Storms; Technical Papers; Transportation planning; Vulnerability; Winter storms
• ISSN: 1527-6988; 1527-6996
• DOI: 10.1061/(ASCE)NH.1527-6996.0000441

AbstractCoastal roadways are vulnerable to changes in landscape that occur at variable spatiotemporal scales. In particular, highways on barrier islands suffer the consequences of the combined action of the ocean, the back-barrier lagoon, and the morphological changes in the island. Coastal dunes and beaches are typically the only barrier between the ocean and the island’s infrastructure, while low-lying marshes separate the infrastructure from back-barrier lagoons. This work addresses the spatiotemporal variability of these coastal features along a barrier island and proposes a set of vulnerability indicators that allow evaluating past, present, and future vulnerability of a coastal roadway. Systematically collected remotely sensed data were used to digitize dune elevations and oceanfront and estuarine shorelines in the northern portion of Hatteras Island, North Carolina, US. Based on these morphological data and their distance to the main roadway on the island, three vulnerability indicators were defined along shore-normal transects: (1) island width