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GZA modeled sediment transport around an important regional marina in Lake Erie using the SWAN (Simulating WAves Nearshore) model and the CMS (Coastal Modeling System)-Flow/CMS-Wave coupled model, informing alternative marina structure designs to mitigate sedimentation. Metocean data analysis, elevation data modification, and hindcasting Wave Information Study (WIS) points identified high water level, Southwest waves as dominant, causing harbor sedimentation, with certain lower probability Northeast conditions anecdotally causing increased sedimentation. GZA developed a SWAN-2D wave model to model waves from the offshore WIS points to the nearshore. GZA then developed a CMS-Wave and CMS-Flow model, using nearshore results from SWAN-2D to simulate waves, flow, and sediment transport in a smaller area around Sturgeon Point Marina. GZA studied 6 scenarios that were combinations of the wave/wind directions of concern, and water level exceedance probabilities. Results from the numerical modeling indicate that during high-water and Southwest wave conditions, sediment transports west along the outer jetty, wraps around the jetty toward shore, and then settles in the mouth of the marina. This same sedimentation location was observed during the Northeast wave condition, with sediment pushing from the East into the mouth of the marina. GZA next completed sediment transport model simulations with 5 different alternative structures/changes in the marina, A sedimentation acceleration factor of 5 times was applied (replicating 5 consecutive storm events), and under dominant storm conditions, the addition of a spur jetty to the eastern end of the outer jetty was seen to reduce sedimentation at the marina entrance the most, by about 60%.