USING HEAT AS A TRACER TO UNDERSTAND GROUNDWATER AND SURFACE WATER INTERACTIONS AT A WETLAND SYSTEM IN MILLEDGEVILLE, GA

Understanding groundwater and surface water interaction remains an important subject in hydrology and wetland studies. The ability of a wetland to sustain its ecological and hydrological functions is strongly dependent on this interaction. In the current study we investigate the transport of water, nutrient and potential contaminants through a wetland system in Milledgeville GA. The wetland system is located at Andalusia Farm, which was historically a plantation until Flannery O’Connor’s uncle bought it for raising horses and cultivated the land for timber, hay, and dairy production. In a previous study at the site, we had utilized nutrients and stable isotopes as a potential parameter for understanding groundwater-surface water interaction. In this study we use temperature, hydraulic head and heat to understand and map areas of upwelling and downwelling in this system. Preliminary results show strong groundwater – surface water coupling in some areas of the wetland system, while other areas did not show any interactions. In areas with strongly coupling, the fluctuations in temperature between groundwater and surface water were strong and synchronized both within and between locations. Three dimensional (3D) map of temperature and hydraulic head distributions will be created and the rates of transport through the system will be modeled using both MODFLOW and VS2DHI. To fully understand the groundwater flow paths in this system, a dye tracing study is also being initiated at the site.