Hydrogeologic mapping and aquifer vulnerability modeling in Florida: 2D and 3D data analysis and visualization

Data analysis and modeling within the infrastructure of geographic information systems (GIS) applications are invaluable assets with respect to groundwater resource management and protection. In Florida, ground water comprises more than 90% of potable water resources, which are used by a population of more than 16 million. With an increase of more than 7000 residents per week, demands on Florida’s ground-water resources continue to intensify in highly populated areas, especially in the midst of a five-year drought. Hydrogeologic research framed around application of 2D and 3D software tools allows simple and clear visual representation of natural systems and processes that need to be understood by environmental managers and elected officials. Two hydrogeology projects utilizing such tools are underway at the Florida Geological Survey (FGS). The first of these projects, the Southwest Florida Subsurface Mapping Project, is developing structure contour and isopach maps for seven lithostratigraphic units and four hydrostratigraphic units over a 14,500 mi. (37,500 km) region based on geologic data from more than 1,050 wells (Figure 1). The study area includes a 10-mile wide buffer zone to help address edge control issues. Lithologic samples from most of these wells have been inspected for lithostratigraphic and hydrogeologic characteristics via binocular microscope. H and geophysical data have also been interpreted to yield point elevations. The goal of this mapping effort is to deliver a highly resolved geologic framework of southwest Florida for use in water resource protection efforts. This hydrog framework will be delivered as map sheets, an ArcView 3.2a (AV) project and an interactive ArcIMS Internet application. The second project discussed herein is the Florida Aquifer Vulnerability Assessment (FAVA) project. FAVA is a develop methodology using GIS as a tool for predicting the relative contamination potential of Florida’s gro water resources. Current plans for delivery of this product include map sheets and an ArcView 3.2a project with a user interface to allow adjustment of parameters. We envision this vulnerability m effort to be contaminant-specific and scalable. Figure 1. SW Florida Subsurface Mapping Project study area and well locations. ydrologic