Predicting Sediment Transport Under Rising Seas: Quantifying Shoreline Change in Hampton Roads Region of Virginia

Coastal communities are threatened by accelerating sea level rise (SLR) with increasing flood intensity and beach erosion globally. Understanding the long-term beach morphology requires utilizing physics-based models that solve cross-shore and longshore sediment transport. Few studies have looked at the role of SLR on local hydrodynamic and morphodynamic interactions. In this study, a widely used computational model that can simulate hydrodynamics and sediment transport, namely Delft3D, is used to calculate long-term evolution of coastlines of Southeast Virginia. This region is being impacted more strongly by SLR compared to other regions along the U.S. East coast due to vertical land motion along with glacial isostatic rebound, in addition to global SLR and regional ocean dynamics. This sea level change along with projected stronger storms will alter the current sediment transport patterns by producing larger waves and increased erosion. The goal of this project is to develop and validate a predictive modeling framework for coastal hydrodynamics, sediment transport, and long-term shoreline erosion under SLR. Beaches in Virginia Beach and Norfolk undergo periodic beach nourishments and have preexisting profile surveys and monitoring, as well as local tide and wave gauges thus there is data for model validation. The resulting developed modeling framework can be generalized to other geographic regions with high rates of erosion to assess their vulnerabilities to SLR.