Intermodal Freight Transportation Planning using Commodity Flow DataBy Zhang Y.,Bowden Jr., Allen A.,
This paper shows that many of the statewide inter-modal freight transportation planning methodologies are based on the Reebie Associates’ TRANSEARCH database because it is assumed as the best commodity flow data currently available. Although TRANSEARCH database has the advantage of having the county level data (thus eliminating the trouble of developing breakdown methodology from state level data), the database is very expensive also has limitations. The Commodity Flow Survey (CFS) data, published by Bureau of the Census, on the other hand, can be used to develop a more economical and flexible inter-modal transportation planning methodology. Although limitations exist, some of those can be improved with further study (such as the case with incomplete data).
The objective of this study is to develop a methodology for statewide inter-modal transportation planning by using public domain database. The State of Mississippi is used in this study as an example to describe the freight movement characteristics. Since the methods derived are intended to be adaptable for use by other states, the methodology needs to be flexible especially when more detailed or updated data become available over time. Utilization of public domain data instead of commercial data is the key to a flexible and economical planning methodology.
The study includes the following three major components:
o Commodity flow data analysis
o Transportation planning model
o Inter-modal transportation simulation model
The three components are integrated to derive the methodologies for statewide inter-modal transportation planning. Different components interact with each other. Many states have already developed their statewide passenger transportation planning models using the traditional four-step model. Common passenger transportation planning models and procedures have been established since passenger transportation data are easier to obtain than freight data. However, there is no standard freight transportation planning model up to date.