MITIGATION OF BEACH EROSIONAL HOTSPOTS WITH COASTAL STRUCTURES: THE USE OF MORPHOLOGICAL MODELS TO OPTIMIZE THE BALANCE BETWEEN SAND RETENTION AND DOWNDRIFT IMPACTS

Although eroded beaches can be restored in many ways, beach nourishment is the preferred method of shore protection in the United States (Elko et al., 2021). While evaluating the performance of constructed beach nourishment projects, additional attention is generally given to the development of erosional hot spots (EHS) within the project boundaries. EHS erodes faster than the average rate of the project erosion and can negatively affect the overall performance of a beach nourishment project. Several parameters have been historically used to identify EHS such as percentage of fill remaining in a specific beach segment vs. the entire fill area (Stauble, 1994) and comparison of erosion rates of specified beach segments with the average rate of erosion of the entire project (Benedet., et. al., 2007). EHS can pose severe challenges to coastal management, damage to infrastructure, loss of habitat and hazards to beachgoers. The occurrence of an EHS within a nourishment project can also significantly shorten the design lifetime of the project.