Hydrodynamic and Sediment Transport, Mill Cove, St. Johns River, Florida:Numerical Modeling Study

摘要

The U.S. Army Engineer District, Jacksonville, is investigating how to improvetidal flushing in Mill Cove, lower St Johns River, Florida, to maintain water quality and to prevent excessive sedimentation. Four plans have been proposed to reshape the shoreline within the cove. One additional proposed plan will also moldy the bathymetry in the area. RMA2-WES, a two-dimensional, vertically averaged hydrodynamic model, was used to compare the circulation patterns that occur in the present day Mill Cove against the circulation patterns that would result from the five plan configurations. Sediment transport was simulated using SED2D-WES, a two-dimensional, vertically averaged model of sediment advection and dispersion in the water column, with the channel bed acting as a source and/or sink for sediment as it deposits and erodes. Currents and tides were compared to prototype data to validate the numerical model. The study addressed changes within Mill Cove as well as any influence these changes had in the navigation channel.