Water Resources Research Act Program

Details for Project ID 2009MD192B

Nearshore sediment inputs due to shore erosion in the Maryland Chesapeake Bay

Institute: Maryland
Year Established: 2009 Start Date: 2009-03-01 End Date: 2010-02-28
Total Federal Funds: $19,392 Total Non-Federal Funds: $38,835

Principal Investigators: Lawrence Sanford, Lawrence Sanford

Abstract: Re-establishment of Submerged Aquatic Vegetation (SAV) beds and associated nearshore habitat is a central goal of the Chesapeake Bay Program. SAV are currently limited by both water column turbidity due to fine suspended sediment and the availability of suitable sandy substrate (approximately 65% sand). Shoreline erosion is the dominant source of both sediment types in nearshore Chesapeake Bay waters. In order to more closely estimate potential nearshore sediment inputs in Maryland’s Chesapeake Bay due to shoreline erosion, we will utilize newly available data sets as well as empirical and theoretical models. Our first objective in quantifying these estimates is to create a sediment budget for the near shore environment that includes sands and fines from shoreline erosion, associated nearshore bottom sediment erosion, and potential onshore transport of sand bars. In the summer of 2008 we occupied ten sites along the Maryland shoreline of the Chesapeake Bay in cooperation with the Maryland Geological Survey, supported by a Department of Natural Resources Coastal Zone Management grant, “Shoreline Erosion, Sea level Rise, and the Bruun Profile”. This data set includes a series of bathymetric profiles in the nearshore region at each site, as well as sediment core data that were acquired along each transect. Further analysis of this data, as well as existing historical shoreline change data sets (MGS, VIMS) and shoreface elevations and sediment distributions (MGS) will allow us to test whether the observed rates of shoreline retreat can be explained by simple shoreward translation of an equilibrium depth profile, given the historical rate of sea level rise. The results of this analysis will provide input to models of system equilibrium/disequilibrium, leading to conclusions on the effects of environmental factors such as anticipated wave power, sediment type, seasonal changes, and sea level rise. The final result will be improved estimates of changes in sand and fine sediment inputs in nearshore Bay waters due to different sea level rise scenarios. We will disseminate these results and engage in discussion with colleagues by organizing a Chesapeake Bay Program Scientific and Technical Advisory Committee (CBP STAC) workshop on shoreline erosion and nearshore water quality.