SEDIMENT TRANSPORT ANALYSIS FOR THE VIRGINIA OFFSHORE WIND TECHNOLOGY ADVANCEMENT PROJECT
Prepared For: Tetra Tech, Inc. 4101 Cox Road, Suite 120 Glen Allen, VA 23060 Prepared By: Woods Hole Group, Inc. 81 Technology Park Drive East Falmouth, MA 02536 December 2013
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Woods Hole Group
EXECUTIVE SUMMARY Woods Hole Group is pleased to provide this report presenting the sediment transport analysis related to the proposed Virginia Offshore Wind Technology Advancement Project (VOWTAP or Project) for Demonstration of an Innovative Offshore Wind System for Virginia Electric and Power Company, a wholly-owned subsidiary of Dominion Resources, Inc. (Dominion). The analysis was developed specifically for a planning level assessment of sediment transport potential associated with the installation of the Project’s proposed submarine electric cable between the shoreline and the proposed VOWTAP Research Lease Area located approximately 43 km off the coast of Virginia near the Bureau of Ocean Energy Management (BOEM) commercial Wind Energy Area (WEA). The work performed in this report was done in accordance with the September 11, 2013 Scope of Work. The sediment transport analysis is intended to support the environmental planning/approval process for the Project. The analytical modeling and analysis identifies potential environmental impacts associated with the proposed submarine cable installation activities, specifically related to the concentration of fine sediments in the water column and the footprint and thickness of sediments deposited on the seafloor.. Based on the results of the sediment transport modeling, the following general conclusions can be made: • • •
The concentration and settling thickness of the sediment plume is dependent on the strength of ambient tidal currents and the volume of fine material in the trench. The fine particles (
