Virginia Institute of Marine Science
Shoreline evolution is the change in shore position through time. In fact, it is the material resistance of the coastal geologic underpinnings against the impinging hydrodynamic (and aerodynamic) forces. Along the shores of Chesapeake Bay, it is a process-response system. The processes at work include winds, waves, tides and currents, which shape and modify coastlines by eroding, transporting and depositing sediments. The shoreline is commonly plotted and measured to provide a rate of change but it is as important to understand the geomorphic patterns of change. Shore analysis provides the basis to know how a particular coast has changed through time and how it might proceed in the future.
The purpose of this report is to document how dunes on the Potomac River and Chesapeake Bay shores of Northumberland (Figure 1) has evolved since 1937. Aerial imagery was taken for most of the Bay region beginning that year, and it is this imagery that allows one to assess the geomorphic nature of shore change. Aerial imagery shows how the coast has changed, how beaches, dunes, bars, and spits have grown or decayed,how barriers have breached, how inlets have changed course, and how one shore type has displaced another or has not changed at all. Shore change is a natural process but, quite often, the impacts of man through shore hardening or inlet stabilization come to dominate a given shore reach. Most of the change in shore positions will be quantified in this report. Others, particularly very irregular coasts, around inlets, and other complicated areas will be subject to interpretation.
Shoreline Evolution, Northumberland County, Chesapeake Bay, beach erosion, Aerial Photography, Human impact, GIS
This project was funded by the Virginia Department of Environmental Quality’s Coastal Resources Management Program through Grants NA17OZ2355, NA17OZ1142,and NA04NOS4190060 ofthe National Oceanic and Atmospheric Administration, Office of Ocean and Coastal Resource Management, under the Coastal Zone Management Act of 1972, as amended.
Hardaway, C., Milligan, D. A., Varnell, L. M., Wilcox, C. A., & Thomas, G. R. (2006) Shoreline evolution, Chesapeake Bay and Potomac River shorelines, Northumberland County, Virginia. Virginia Institute of Marine Science, William & Mary. https://doi.org/10.25773/bgrw-bf94