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Hurricanes can benefit wetland accretion by augmenting the delivery of mineral sediment, an essential process allowing marshes to offset submergence during rising sea levels. Using Hurricane Gustav (2008, Louisiana) as a control, we examined eight synthetic storms with varying characteristics (track, speed, intensity, size) to evaluate sediment exchange between the inner shelf and bay and bay‐to‐marsh interfaces. All storms showed net landward sediment exchange from the inner shelf to the bay to the marsh—storms with closer proximity, higher intensity, and slower forward speed positively correlated with net sediment exchange; storm size had little impact. Except for slow‐moving storms (½ speed of Gustav), our analyses suggest that most hurricane scenarios cause net bay erosion, because more sediment is conveyed to landward wetlands than is replenished from erosion of the inner shelf. Our results suggest that the ongoing deepening of the bay will likely worsen because of rising sea levels 

When longshore transport systems encounter tidal inlets, complex mechanisms are involved in bypassing sand to downdrift barriers. Here, this process is examined at Plum Island Sound and Essex Inlets, Massachusetts, USA. One major finding from this study is that sand is transferred along the coast—especially at tidal inlets—by parcels, in discrete steps, and over decadal-scale periods. The southerly orientation of the main-ebb channel at Plum Island Sound, coupled with the landward migration of bars from the ebb delta to the central portion of the downdrift Castle Neck barrier island, have formed a beach protuberance. During the constructional phase, sand is sequestered at the protuberance and the spit-end of the barrier becomes sediment starved, leading to shoreline retreat and a broadening of the spit platform at the mouth to Essex Bay (downdrift side of Castle Neck). Storm-induced sand transport from erosion of the spit and across the spit platform is washed into Essex Bay, filling channels and enlarging flood deltas. This study illustrates the pathways and processes of sand transfer along the shoreline of a barrier-island/tidal-inlet system and provides an important example of the processes that future hydrodynamic and sediment-transport modeling should strive to replicate.