Effects of Chronic and Acute Stressors on Hydro-Morphodynamics Processes in a Rapidly Changing Coastal Inlet System: A Case Study at the Rachel Carson Reserve, North Carolina

Tuesday, May 20, 2025

4:45 PM – 5:00 PM Alaska Daylight Time (AKDT)

Room: Room 2

Author(s)

Swarna Chowdhury (she/her/hers)

Graduate Student
North Carolina State University, North Carolina, United States

Co-Author (not attending)(s)

Celso Castro Bolinaga (he/him/his)

Associate professor
Department of Biological and Agricultural Engineering, NCSU, North Carolina, United States
Evelynn Wilcox

undergraduate Student
Dept. of Biological and Agricultural Engineering, NC State University, United States
Grace Massey

Virginia Institute of Marine Sciences, USA, United States
Paula Gillikin

N.C. Coastal Reserve & National Estuarine Research Reserve, Division of Coastal Management, North Carolina Department of Environmental Quality, USA, United States
Justin Ridge

N.C. Coastal Reserve & National Estuarine Research Reserve, Division of Coastal Management, North Carolina Department of Environmental Quality, USA, United States
Nina Stark

Associate Professor
Department of Civil & Coastal Engineering, University of Florida, United States
Steven Hall

William White Distinguished Professor
North Carolina State University, United States

Abstract Submission: Over the past 60 years, the changing geomorphology of the Beaufort Inlet, located just south of the Rachel Carson Reserve (RCR) in North Carolina, has had a direct effect on shoreline migration and sediment dynamics at the RCR. These changes have impacted the vulnerability of coastal habitats (e.g., salt marshes and bivalves) in the face of chronic and acute stressors, including the progressive widening of the Beaufort Inlet and the occurrence of hurricanes. Understanding the compounding effects of such stressors on the hydro-morphodynamic processes driving geomorphic changes at the RCR is therefore critical to assess the vulnerability of coastal habitats and to inform effective resilience planning. The objectives of this work were twofold. First, to determine the mechanisms through which the changing geomorphology of the Beaufort Inlet has been driving shoreline migration and sediment dynamics; and secondly, to examine the degree of geomorphological change caused by hurricanes and its impacts on the vulnerability of critical habitats. To address these objectives, a multifaceted field effort was conducted to characterize flow and sediment transport conditions, as well as bed erodibility and composition. These data were then used to inform the construction and calibration of a 2D numerical model, which was applied, first, to hindcast drivers of observed geomorphic changes caused by chronic inlet widening, and secondly, to forecast the impact of acute stressors (hurricanes) on hydro-morphodynamic processes and their future ability to drive change. Ultimately, this work aims to provide valuable insights for management and conservation planning in coastal environments.

Learning Objectives/Expected Outcome (Optional) :