A FVCOM study of the potential coastal flooding in apponagansett bay and clarks cove, Dartmouth Town (MA)

Abstract

A high-resolution Finite-Volume Coastal Ocean Model (FVCOM) inundation model has been developed for Dartmouth Town near Apponagansett Bay and Clarks Cove. Series of modeling experiments were conducted for the purpose of: (1) Assess the potential impacts of the climate-induced Sea Level Rise (SLR) on the storm-induced coastal inundation in Dartmouth Town; (2) Compare the current patterns, wave fields and surge distributions under different dynamic forces including winds in different directions and wave-current interaction; (3) Evaluate the impact of the bank on the flooding protection. Results show that under the hundred-year nor’easter storm condition, the climate-induced SLR could significantly enlarge possible flooding areas with the percent area enlargement of approximately 60% per foot of SLR. The directions of wind essentially determine the feature of the current patterns, wave and surge distributions. The northeasterly and easterly winds mainly threaten the western coast of the bay and the estuarine areas, and the southerly and southeasterly winds endanger the regions around the inner part of the bay. Wave-current interaction can change the current pattern nearshore, including formation of eddies and narrow alongshore currents, greatly enhancing the strength and complexity of the currents near the mouth of the bay. In addition, wave-induced surge tends to accumulate in the bay and near the estuary and coastal regions. The bank blocks a large amount of flooding current and waves into the bay and improves the local current and wave condition effectively near the mouth and in the bay.