Study of Groundwater-Surface Water Interactions to Identify Potential Aquitard Breach Locations along the Wolf River, Tennessee

Inter-aquifer exchanges due to breaches in the confining clay layer can potentially contaminate the Memphis aquifer, as lesser-quality waters permeate from the unconfined aquifer. Losing river reaches could indicate breach locations, as these should depress water-table locally, resulting in downward vertical exchange fluxes (VEFs) along nearby streambeds. A spatial analysis of seepage meter measurements performed along the Wolf River identified three potentially losing sub-reaches, where VEFs were studied at a finer scale, using multiple point-scale methods. Results were mixed, displaying large spatial variability, possibly due to mismatches between the process and observation scales. Differential stream gaging was conducted to assess losses integrally over sub-reaches, confirming one losing location; however, comparing groundwater river stages suggested gaining conditions at this location. Pinpointing losing reaches using point-scale methods is difficult due to the disparity of scales. Effective methodologies are needed that comply with the scale of the problem