Bypassing at inlets can occur across the ebb shoal, through tidal exchange, and byrnepisodic collapse of shoals. To examine ebb-shoal and tidal exchange bypassing in a systematicrnway, we investigated sediment pathways at an idealized inlet with a coupled tide, wave, andrnsediment transport-morphology change numerical modeling system. The idealized inlet, ebbrnshoal, and channel were devised to test the coupled modeling system and isolate sedimentrntransport pathways driven by wave and tidal forcing. The inlet, channel, ebb shoal, and bayrndimensions approximate those of Shinnecock Inlet, New York. Five simulations consisting ofrntide forcing, wave forcing (fair-weather and storm), and combined tide and wave forcing werernconducted. Patterns of calculated morphology change followed those found in nature.rnSimulations with waves impounded sand against the updrift jetty and eroded the bottom in thernnearshore area on the downdrift side of the inlet. Wave breaking on the ebb shoal primarilyrnmoved material updrift, but also flattened the shoal by eroding the top and depositing materialrnaround its perimeter. For the forcing conditions examined, waves were the dominant transportrnmechanism. Tidal currents modified the morphology change primarily at the inlet entrance andrnon the updrift side of the ebb shoal by opposing the current during the flood tide.
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