Profile Equilibration and Longshore Spreading Associated with Beach Nourishment: A Case Study Along West-Central Florida Coast

This paper examines profile equilibration and longshore spreading associated with beach nourishment based on weekly to monthly profile surveys along the west-central Florida coast. Profile equilibration occurred rapidly and was largely completed after the first post-fill storm, typically with the formation of a nearshore bar and the overall beach-profile slope approaching the pre-nourishment slope. The bar moved offshore and onshore in response to subsequent storm and calm-weather conditions, respectively, while shoreline position remains largely stable. Longshore spreading is strongly influenced by grain size. Fine sand (~ 0.20 mm) tends to be transported and deposited along the nearshore bar resulting in little change along the shorelines and on the dry beach. The coarser shell debris tends to spread along the shoreface through the growth of a diffusion spit, which abruptly changed the shoreline orientation at the ends of project.