Critical Width of Barrier Islands and Implications for Engineering Design

The critical width of a barrier island is defined as the smallest cross-shore dimension that minimizes net loss of sediment from the island over periods from decades to centuries. This concept is of importance for large-scale restoration of barrier islands which involves rebuilding these islands to a specified geometry. Within constraints of coastal forcing and geologic and regional characteristics at the site, islands having critical width will capture deposition of washover sediment onto the subaerial beach over the project lifetime. This study reviews previous investigations of barrier island critical width and applies a newly-developed model of barrier island migration, consolidation, and overwash to assist engineering design.