ESTUARINE SHORELINE PLANNING AND MANAGEMENT IN SOUTH CAROLINA

The South Carolina Beachfront Management Act and associated regulations were adopted in 1988, and over the past two decades these rules have limited the development and hard stabilization of ocean shorelines in many areas. However, as beachfront lots have become increasingly scarce, estuarine shorelines have become equally desirable for development. These shorelines face similar threats from erosion, sea level rise, and storm events, as well as increased demand for erosion control structures and other alterations. Complex regulatory, economic, environmental, and legal issues, together with natural and socioeconomic data limitations, result in an unclear understanding of future estuarine shoreline changes in South Carolina, and our ability to adapt to those changes.

Unlike the ocean shorelines in the State, bulkheads and revetments are typically allowed along eroding estuarine shorelines. However, the extent of estuarine shorelines that are armored is presently unknown and trends in numbers and distribution of structures are difficult to evaluate because permits were not consistently tracked prior to 2001. From 2001 through 2009, the South Carolina Department of Health and Environmental Control – Office of Ocean and Coastal Resource Management (SCDHEC-OCRM) issued 1,067 permits for erosion control structures along eroding estuarine shorelines. This large number of permits in the last decade indicates that erosion is a common concern along South Carolina’s estuarine shorelines, and armoring is the preferred mitigation approach.

Erosion control structures along estuarine shorelines prevent inland migration of the marsh as sea level rises, and they often change the hydrodynamics of tidal creek channels by causing current velocities to increase. In turn, the increased currents can prevent fine sediment from settling out of the water column and can reduce nourishment to the nearby marshes. A single erosion control structure may not have a dramatic negative impact on the estuarine environment, but the cumulative impacts of hundreds, or even thousands, of structures in the coastal zone must be considered.

Estuarine shoreline mapping and monitoring is needed to determine present and historical shoreline positions, erosion rates, and cumulative lengths of armoring so that effective management policies can be developed.