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The purpose of this study is to address environmental issues raised by the potential for dredging sand from the inner continental shelf offshore Alabama for beach replenishment purposes. In cooperation with the State, the MMS identified five potential sites of high-quality sand deposits in Federal waters. Five study elements were identified for addressing the study purpose. They include: 1) quantify the potential modifications to waves and currents that cross within the identified borrow areas due to offshore dredging; 2) quantify the impacts of offshore dredging and consequent beach nourishment on local and regional sediment transport patterns, coastal and nearshore sedimentary environments, and local shoreline processes; 3) assess baseline benthic ecological conditions in and around the proposed sand borrow areas; 4) evaluate benthic infauna resident in the potential borrow sites and assessment of potential effects of offshore dredging on these organisms, including an analysis of the potential rate and success of recolonization following cessation of dredging; and 5) develop a schedule of best and worst times for offshore dredging with regards to transitory, pelagic species.

Applied Coastal personnel evaluated the current and circulation component of study element 1 and study element 2 using previously collected coastal processes data sets (waves, currents, winds), ADCP data collection efforts for spring and fall surveys, and wave transformation numerical model results. Sediment transport estimates along the shoreline and in the nearshore were determined from wave and current analyses, as well as historical shoreline and bathymetric change data sets. The information gathered and analyzed during the course of this study will enable MMS to monitor and assess the potential impacts of offshore dredging activities and to identify ways in which dredging operations can be conducted to minimize or preclude long-term adverse impacts to the environment.

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