Williams, H.F.L. and Rains, B.J., 2022. Effect of barrier height on magnitude and character of Hurricane Harvey washover fans, Matagorda Peninsula, Texas, U.S.A. Journal of Coastal Research, 38(1), 133–139. Coconut Creek (Florida), ISSN 0749-0208.
This study uses topographic profiles, washover fan volumes, and shoreline retreat rates to explore relationships between barrier height, erosion, and storm washover sedimentation. Pre- and post-Hurricane Harvey topographic profiles were created along 15 transects using Bare Earth LIDAR (2016) and transit level surveys (2019). Washover fan thicknesses and areas were measured to estimate washover fan volumes. An inverse relationship was found between washover fan volume and pre- and poststorm barrier heights. One section of shoreline had a prestorm height of about 3 m, which almost completely blocked overwash, but may have contributed to a large increase in shoreline erosion. In contrast, a section of shoreline with a low prestorm barrier generated relatively large washover fans, but experienced lower shoreline retreat and was the only section to experience beach and dune recovery in the year after landfall. Shoreline retreat was further quantified between 2014 and 2018 using Google Earth imagery and LIDAR data from 2014, 2016, 2017, and 2018 to track migration of the shoreline. The entire shoreline in the study area is undergoing relatively rapid retreat, but the results suggest that Hurricane Harvey increased erosional retreat rates by up to 195%. The Colorado River Jetty borders the study area and may have acted as a barrier to wave erosion, contributing to enhanced marsh aggradation at marsh sites in close proximity to the jetty and promoting shoreline recovery in the poststorm period. The research results provide valuable information on the interaction of hurricane storm surge with natural and anthropogenic barriers, beach and dune erosion, and marsh aggradation along the coast of Texas.