Intermodal Freight GIS Network

The high cost of diesel during the summer of 2008 made the public aware of the impact transportation has on the costs of consumer products. For this reason, it is imperative that shippers use economical and efficient means of transporting goods to market. Instead of relying solely on truck transportation, intermodal freight transportation solutions are increasingly being found to be environmentally friendly and economically competitive. Intermodal freight transportation has unique challenges, including conditions of terminal access roads, congestion in and around the terminal and traditional freight transportation planning seldom considers all modes of transportation.

James Dobbins, in a project funded by the Memphis Intermodal Freight Transportation Institute (IFTI), is developing an intermodal freight transportation geographic information system (GIS) network that will simulate intermodal movements throughout the southeastern U.S. This network will enable what-if scenarios, identify bottlenecks, and allow transportation planning professionals to perform freight transportation planning with a comprehensive view of freight operations within their area. Starting with the National Transportation Atlas Database (NTAD) highway, rail and waterway networks, researchers needed to make connections at containerized intermodal terminals. However, in many cases it wasn’t clear where the connections actually took place. By creating a Google Earth layer of terminals and using the underlying satellite imagery to verify terminal locations, researchers eliminated non-containerized terminals from consideration and adjusted terminal locations to represent the locations where containers actually change modes.

With precise locations identified for modal connections, the network has been recently completed and the first set of shipments routed successfully from origin to destination. Dobbins is modifying the network so that network link attributes (speed, congestion, impedance) accurately represent current conditions. The second year of this effort includes developing a more detailed means of representing terminal capacity. It is hoped that transportation planning professionals will be able to make extensive use of the network and understand flows through and within their jurisdictions.