(Georgia Institute of Technology, 2011-04)
Rugel, Kathleen; Golladay, Stephen W.; Jackson, C. Rhett
Many streams in the lower Flint River Basin are hydraulically connected to the underlying Upper Floridan Aquifer which supplies millions of gallons of water per day to irrigated agriculture throughout the Coastal Plain province of Georgia. Extensive pumping of surface and groundwater within the lower Flint River Basin has resulted in significant streamflow declines, threatening aquatic species which are listed as endangered and threatened in this region. Our research focuses on detecting fracture and dissolution paths between Ichawaynochaway Creek and the underlying Upper Floridan Aquifer. We collected and analyzed stream samples for NO3 -, Ca+, δ18O, and δD, as well as specific conductivity, temperature and pH, at 1 km intervals along a 53 km reach of the Ichawaynochaway Creek in southwestern Georgia, USA. We hypothesized that stream reaches within close proximity to fractures and joints would reflect the chemical signature of inputs from the underlying aquifer. We compared stream chemistry with proximity to various surface features visible on remote sensing data sets in order to identify geomorphological characteristics which might be associated with and predictive of stream-aquifer exchange.