Applied Coastal Research Laboratory director helping to preserve key archaeological sites

The coast is one of Georgia’s most precious natural treasures, but the pounding waves, rising tides and meandering rivers that make such important contributions to the region’s beauty and ecological diversity are also exacting a heavy toll on an irreplaceable part of the state’s history. Slowly and surely, the forces of erosion are destroying numerous archaeological sites that range from earthen forts used during the Civil War to villages that were once inhabited by Native Americans and pre-historic humans. Georgia Southern University scientist Clark Alexander is working with the Georgia Department of Natural Resources (DNR) on a project that is helping archaeologists document the sites before they succumb to the ravages of time. Specifically, Alexander has been compiling data that identifies the sites that are in the most eminent danger. ‘Archaeological sites are non-renewable resources,” said Alexander, the director of Georgia Southern’s Applied Coastal Research Laboratory (ACRL) and an adjunct faculty member in the University’s Department of Geology and Geography. ‘Once a site has been lost, it cannot be replaced, and the information it contained is lost forever. ‘It is not always feasible to preserve sites in this dynamic coastal environment because of the easily eroded sediments and constant exposure to tidal currents and storms. Therefore, documentation of the sites before they are lost is critical.” Enter the ACRL, which is part of the Allen E. Paulson College of Science and Technology (COST) at Georgia Southern. The lab is located on Skidaway Island near Savannah. ‘We are interested in supporting coastal, estuarine and marine research in all its facets, whether in geology, biology, chemistry, economics, history or archaeology,” Alexander said. ‘As the University’s field laboratory, we are uniquely situated to facilitate coastal scholarship by faculty and students from COST and the main campus as a whole by providing access to and understanding of coastal Georgia. ‘We also feel strongly that the ACRL needs to form partnerships with other state agencies and universities in order to maximize our citizens’ interest in coastal research and management, and then take the results to a state-wide audience.” To that end, the ACRL joined forces with the state DNR’s Historic Preservation Division and Coastal Resources Division, which includes the Georgia Underwater Archaeology Program. Alexander and state archaeologist David Crass submitted a proposal for a project that would prioritize archaeological sites for study based on their erosion rates. The two scientists were awarded a Coastal Incentive Grant for $49,794 from the Georgia Coastal Zone Management Program. ‘Coastal areas have been a focal point for civilizations throughout history,” Alexander said. ‘As a result, much of a region’s cultural, political and commercial history can be interpreted by examining coastal sites.” Although Georgia’s coast extends for ‘only” 100 miles from Florida to South Carolina, the state contains over 1,200 miles of shoreline, thanks to countless inlets and islands. ‘Coastal Georgia is a dynamic environment,” Alexander said. ‘The natural forces of wind and water have formed and changed the shape of our coastline over the centuries, and continue to erode coastal landforms and deposit the material elsewhere, sometimes dramatically. ‘Frequently, shoreline erosion along coastlines and bluffs of tidal streams impacts important archaeological sites by exposing, removing and destroying burials, features and artifacts. These are things that could have provided important information for interpreting and managing the sites, and for enhancing our understanding of the settlement and use of coastal Georgia.” Unfortunately, because of their sheer numbers, many of Coastal Georgia’s archaeological sites have not been closely examined by scientists. At the same time, these naturally vulnerable sites have been attracting all of Mother Nature’s relentlessly destructive attention. ‘Mapping and documenting the thousands of archaeological sites on the Georgia coast is a daunting task,” Alexander said. ‘The resources in both manpower and time are beyond that which is available to the Historic Preservation Division of the DNR. ‘Archaeological surveys have been conducted piecemeal over the years, but up to now there has been no systematic investigation of the coast, either to identify sites, determine the condition of existing sites, or assess damage to significant sites caused by coastal erosion.” To get an idea of the extent of the problem, Alexander and Crass performed a pilot study with Historic Preservation Division archaeologists at three locations in Chatham County. They calculated the rate of erosion over a 72-year period by measuring the distance between a 1933 shoreline provided by the National Oceanic and Atmospheric Administration and a 2005 shoreline mapped with the ACRL’s high-resolution Global Positioning System. The study revealed that:

• On Green Island on Ossabaw Sound, the shoreline had retreated approximately 99 feet, causing a Civil War-era earthen fort to be lost at a rate of about 1.4 feet per year.
• Along Newell Creek on Ossabaw Island, the shoreline had retreated approximately 103 feet, causing a site that contains both prehistoric and plantation-era resources to be destroyed at a rate of about 1.4 feet per year.
• Near Groves Creek on Skidaway Island, the shoreline had retreated approximately 84 feet, causing a significant Native American village from the 16th and 17th centuries to be lost at a rate of about 1.2 feet per year.

‘In each case, poorly documented prehistoric and/or historic resources are being lost to channel migration and shoreline or bluff retreat,” Alexander said. ‘The problem is of such magnitude and the erosive processes so inexorable in their power, that it is beyond the ability of most landowners, whether they are government agencies or private individuals, to protect the sites for any length of time. ‘Documentation of these sites before they are lost is critical if we hope to record any of the history contained with them.” As the project continues, the ACRL is providing critical Geographic Information System services by creating working maps of areas of historic interest. The maps display boundaries of land, water and cultural resources at different time periods. ‘These historic map comparisons are very important because over tens to hundreds of years, river channels migrate and waterfront properties are abandoned or buried or eroded away,” Alexander said. ‘That means you can easily look in the wrong place for sites that might have been waterfront in the past. ‘For example, we created a map showing the 1865 shoreline of the Ogeechee River and Fort McAllister compared to the modern location of these features. This allowed a state archaeologist to generalize where cannon balls would have been falling during a Civil War battle, thus enabling him to search for these artifacts.” Alexander was recently honored by the Historic Preservation Division of the state DNR for his efforts. He was presented with a Preservation Achievement Award, which is given annually to individuals and organizations that have made significant contributions to historic preservation in Georgia. ‘Because of its size, this project must be carried out in phases, the first of which is targeting those sites in danger of destruction from erosion,” Alexander said. ‘Our work will provide a prioritized list of sites so that the limited resources can be focused on the most susceptible targets. “Other sources of funds for this work are not available because little is presently known about the integrity or extent of many of these sites. Before funding for site investigations can be obtained from other sources, the significance and integrity of the known sites must be ascertained.”