Using GIS to Analyze and Model a Closed Stormwater Basin in Ocala, Florida

Geographic Information Systems (GIS) technology has become a valuable resource in stormwater modeling and planning. GIS technology has evolved to the point where it is becoming commonplace on the engineering desktop. Much of the functionality that was limited to specialists only a few years ago is now available through both readily accessible public domain tools as well as commercial packages. This paper describes how GIS was used in the analysis of a closed stormwater basins in Ocala, Florida, using a combination of public domain tools and standard GIS software with no additional programming or customization. Hydrological applications included using digital topographical data to delineate subbasins and generate flowpaths and slopes, obtaining percent imperviousness from orthophotos, and determining soil type percentages for each subbasin. Hydraulic applications included generating the components of a stormwater model (e.g., stage-area relationships and connectivity) and mapping the flooded areas based on model results. By way of an example application, this paper demonstrates how GIS tools have evolved to point where they maybe used as a standard engineering desktop application to improve the efficiency, accuracy, and clarity of stormwater modeling and planning projects without the need for highly specialized GIS training.