Scientific Studies

To better understand the processes of saltwater contamination and to monitor ground-water conditions in coastal Georgia, the U.S. Geological Survey (USGS) is participating in cooperative studies with the Georgia Environmental Protection Division (GaEPD), and the City of Brunswick and Glynn County, Georgia.

The Sound Science Initiative

The Coastal Georgia Sound Science Initiative is a program of scientific and feasibility studies to support development of GaEPD's final strategy to protect the Upper Floridan aquifer from saltwater contamination. Implementation of the final strategy is proposed for January 2006.

In support of the Sound Science Initiative, the USGS is working on a comprehensive program to evaluate ground-water conditions in the coastal area of Georgia and adjacent parts of South Carolina and Florida. The study is being conducted in cooperation with the GaEPD. Other participants include the U.S. Army Corps of Engineers; Georgia Institute of Technology; The Georgia Conservancy; Georgia State University; Georgia Southern University; Skidaway Institute of Oceanography; The University of Georgia, Cooperative Extension Service; the South Carolina Department of Health and Environmental Control; and several private consulting firms.

The objectives of the Sound Science Initiative are:

• Conduct expanded scientific and feasibility studies to determine how to prevent saltwater from moving toward Hilton Head Island, South Carolina, and how to prevent the existing saltwater contamination at Brunswick, Georgia, from worsening.
• Develop a digital ground-water flow model to more completely simulate the flow system by incorporating additional layers in the surficial aquifer, the upper and lower Brunswick aquifers, and the Fernandina permeable zone. Use the calibrated flow model to simulate water-management scenarios and provide input data necessary to simulate chloride movement.
• Investigate paths and rates of ground-water flow and intrusion of saltwater into the Upper Floridan aquifer by developing solute-transport models for the Brunswick and Savannah–Hilton Head Island areas. Use the calibrated models to evaluate rates of saltwater contamination under a variety of water-management scenarios.
• Delineate areas where saltwater enters the Floridan aquifer system by constructing offshore test wells near Savannah–Hilton Head Island, and test wells onshore along the coast.
• Assess alternative and supplemental sources of water supply by conducting studies to evaluate the water-supply potential of (1) seepage ponds connected to the surficial aquifer; (2) the upper and lower Brunswick aquifers; (3) the Lower Floridan aquifer; (4) rivers and streams; (5) off mainstream impoundments; (6) reclaimed water; (7) reverse osmosis; and (8) conservation.
• Develop and maintain an expanded monitoring network to assess ground-water levels and quality.
• Conduct feasibility studies and assessments of engineered and non-engineered methods that could be used to prevent saltwater intrusion.
• Provide scientific rationale to support development of a final strategy to protect ground water in coastal Georgia from saltwater intrusion.

USGS workplan (1.2 Mb Adobe PDF file)