Skip to main content
U.S. flag

An official website of the United States government

Development of a process-based littoral sediment transport model for Dauphin Island, Alabama

February 28, 2020

Dauphin Island, Alabama, located in the Northern Gulf of Mexico just outside of Mobile Bay, is Alabama’s only barrier island and provides an array of historical, natural, and economic resources. The dynamic island shoreline of Dauphin Island evolved across time scales while constantly acted upon by waves and currents during both storms and calm periods. Reductions in the vulnerability and enhancements to the resiliency of Dauphin Island—through offshore sand placement, breach closure, berm construction, and other means—have been used to protect the island and its vital resources. Planning for a resilient Dauphin Island requires predicting the long-term evolution of the barrier island system and the dominant, temporally varying processes that influence it, including littoral alongshore sediment transport under typical wave conditions, beach and dune erosion, the island overwash and breaching that occur rapidly during storm events, and the recovery of primary sand dunes through Aeolian transport over decadal time scales. Littoral sediment transport within the Dauphin Island decadal-scale framework was simulated using the Delft-3D modeling software suite. The influences of wind, waves, water levels, and sediment transport are incorporated into the model. Model skill in the prediction of waves, water levels, currents, volumetric flow rates through inlets, and shoreline position was assessed by using a set of deterministic and statistical hindcast simulations. The Delft-3D modeling application described here can be coupled with validated models of storm-response and dune recovery to predict the evolution of Dauphin Island on decadal time scales.

Publication Year 2020
Title Development of a process-based littoral sediment transport model for Dauphin Island, Alabama
DOI 10.3133/ofr20201011
Authors Robert L. Jenkins, Joseph W. Long, P. Soupy Dalyander, David M. Thompson, Rangley C. Mickey
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Open-File Report
Series Number 2020-1011
Index ID ofr20201011
Record Source USGS Publications Warehouse
USGS Organization St. Petersburg Coastal and Marine Science Center