Assessment of the 1997 Commodity Flow Survey for State-Level Freight Transportation Planning

Urban travel demand modeling in the United States has a rich history in both practice and academic research. The same cannot be said, however, of freight demand modeling despite the intermodel planning requirements of IS TEA and TEA21. In most instances, agencies responsible for state transportation planning (e.g. Kentucky Transportation Cabinet) have applied, in a limited way, the methodology developed for urban travel demand modeling (i.e., Urban Transportation Modeling System or UTMS 1) to the freight arena (see, for example, Black 1997). Obviously, this methodological similarity implies that the fundamental data requirements for both types of demand modeling are also similar. For example, both models require estimates of the amount of traffic (i.e., number of trips for urban modeling and amount of freight for freight modeling) produced within each zone comprising the study area. Yet, despite such similarities, the two modeling systems differ significantly in terms of the availability of data for modeling purposes.