Geographic information system-based transportation forecast model for small urbanized areas

The geographic information system (GIS) has been demonstrated to be an effective tool for transportation forecasting and scenario analysis. Previous efforts have linked full-function GIS packages with transportation forecasting models. Tools developed to provide a modeling environment more appropriate for the technical knowledge level and budget requirements of small urban or rural areas are described. Specifically, the needs of metropolitan planning organizations and regional planning affiliations in Iowa were considered in the system design. A desktop mapping package, MAPINFO, is integrated with an urban transportation planning model, TRANPLAN, to provide an interface for network analysis. With the system, network modifications and changes representing alternative demand scenarios are made in the GIS environment, and data are exported to the TRANPLAN format, and, after analysis, returned to the GIS for effective presentation of results. User tools were tested and a case study demonstrating alternatives analysis and display capabilities is presented. Although developed and tested for Des Moines, the system can easily be transferred to other agencies to enhance transportation planning capabilities.