Using a Unique 150-Year Geomorphological Cycle in Modern Beach Nourishment Design

Abstract A unique, repeating 150-year geomorphological cycle of migration of a small island onto the beaches of Dauphin Island is being considered in the design of modern beach nourishment projects. We are in the midst of the third such migration in recorded history (since 1699) but there is geomorphological evidence (extremely high sand dunes) that the same cycle has occurred for millennia. The modern beach nourishment projects (2016, 2024, and a third being planned for 2026–27) are being designed to work with this ongoing migration.