Abstract

Interpolating the Potentiometric Surface beneath Wellfields in West-central Florida
Track: Water Resources
Authors: Geoffrey Fouad, Terrie Lee

Near Florida's west-central coast, upward flow from the confined Upper Floridan aquifer discharges into the surficial aquifer, which sustains water levels in hydrologically connected streams and wetlands. Droughts and pumping from large municipal wellfields can diminish or reverse this hydrologic connection thereby reducing surface and groundwater levels along with streamflow. Understanding regional groundwater fluxes requires: (1) mapping the monthly average elevation of the Upper Floridan aquifer's potentiometric surface and (2) minimizing the error inherent in interpolating groundwater elevations. For this project, ESRI interpolation schemes provided by the Geostatistical Analyst suite of tools were applied to groundwater elevations collected over an approximately 200 square mile area containing 11 wellfields. The optimum interpolation technique was selected by interpreting semivariograms according to published standards. Control points were used to determine uncertainty levels. Time series data generated by this project will function as an assessment tool for wetland and stream hydrology.