Mississippi Coastal Improvements Program (MsCIP) barrier island restoration long-term directional wave, circulation, and water level analysis

<jats:p>The Mississippi Sound barrier islands, including Ship Island, protect the Mississippi coast from wave-induced erosion during storms. Hurricane Camille (1969) breached Ship Island, and Hurricane Katrina (2005) widened the Camille Cut, increasing the mainland coast’s exposure to waves. To protect the coast, the US Army Corps of Engineers filled the cut with sand and restored Ship Island to its pre-Camille condition in 2020. To evaluate changes in wave height and potential changes in tides and residual currents, field observations via moorings and roving surveys were conducted pre- (2014–2016) and postrestoration (2022–2024). The tidal range and currents were found to be similar pre- and postrestoration, with slight decreases behind Ship Island. Behind and in front of Ship Is-land, the tidal ellipses shifted to being more shore parallel. The residual currents were primarily wind driven and showed little change in magnitude and direction around Ship Island during both summer and winter conditions. Waves passing through the Camille Cut were reduced, and the ratio of significant wave height behind to in front of Ship Island decreased from 0.40 to 0.25 following restoration. The Ship Island restoration reduced wave heights without significantly changing the tidal and residual currents in the Mississippi Sound.</jats:p>