This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-2).
The study will promote understanding of sediment dispersal in estuaries through an investigation of the Delaware River estuary. Coordinated studies of water-column sediment flux, deposition, and resuspension are planned and the PIs hope to establish the sediment trapping efficiency of the estuary as a function of external forcings, including river discharge, tides and wind. An array of instrumented moorings will be deployed to obtain continuous time-series records of flow and suspended-sediment concentration, and a suite of naturally occurring and anthropogenic radionuclides measured seasonally. Specific objectives are: 1) to identify the sources, transport pathways, and residence times of fine sediment based on distributions of 7Be, 210Pb, and 137Cs; 2) to asses the role of channel morphology on along- and across-estuary patterns of sediment transport and deposition using in-situ observations of sediment flux; and 3) to elucidate the mechanisms of sediment flux and trapping responsible for maintaining the estuary turbidity maximum, and which transfer sediment from the axial channel to subtidal flats.
