Recent Overwash Deposition On Pea Island, NC, USA
Ocean Science and Engineering
Along sandy shorelines, impacting storms can produce washover deposits. Examining these deposits can yield considerable insight into storm inundation processes and flood heights, particularly in areas where directly measured flood heights after events are sparse. Here we examine Pea Island, North Carolina, which is a vulnerable segment of the North Carolina (NC) Outer Banks barrier island chain. Using a combination of imagery, LiDAR, GPR, trenching, and sediment coring, we examined washover deposits associated with Hurricanes Sandy and Isabel, and a 2006 nor’easter. Using grain-size statistics from each event, we apply a widely used inverse sediment transport model to calculate flood heights and compare with calculated wave runup values since observations were unavailable. For Hurricane Sandy and the 2006 nor’easter, the model produced flooding heights consistently higher than the calculated water level estimates. For Hurricane Isabel, the model provided an excellent fit with calculated water level estimates. Insights gained from this study yield additional observations of flood heights in this area, and event scale sediment transport trends.
Coastal Sediments 2023
Gremillion, S. L.,
Wallace, D. J.,
Eisemann, E. R.
(2023). Recent Overwash Deposition On Pea Island, NC, USA. Coastal Sediments 2023, 2332-2339.
Available at: https://aquila.usm.edu/fac_pubs/21010