The Effect of seawall on beach changes under various wave conditions – A case study at Sandy Hook, New Jersey

Mark Vivar

Co-Presenters: Juhi Rawal, Israel Imhomoh

College: Hennings College of Science Mathematics and Technology

Major: BA.EARTHSCI

Faculty Research Mentor: Cheng, Jun  

Abstract:

Many local beaches have erosion control structures, which significantly influence beach morphology. Sandy Hook Beach provides an ideal site to investigate a rock breakwater’s impact on beach morphology. We conducted monthly beach profile surveys, with increased frequency before and after major storm events. Surveys were carried out using RTK-GPS and traditional leveling with rods. Surface sediment samples were collected for grain-size analysis, we analyzed beach profiles to measure morphological changes. Downdrift of the breakwater, significant erosion occurred. Near the breakwater remained mostly stable. Updrift saw noticeable sand accretion. During the October Nor’easter updrift and downdrift sections eroded, and Hurricane Melissa saw erosion and accretion patterns reversed. A machine learning approach was applied to the time series of beach data and corresponding incident wave energy to investigate patterns in the relationship between wave forcing and beach changes. Understanding how breakwaters influence beach morphology under different conditions improves coastal management strategies. These results can guide engineers to design more effective shoreline protection systems.