The shift away from the use of a single mode of transportation for a shipment in favour of an intermodal approach is an important trend in contemporary freight transportation. Integrated intermodal freight transportation in the U.S. primarily consists of services combining railroads, motor carriers, and steamship lines. Until the 1980s, intermodal services attracted cost conscious shippers of low value, non-time sensitive commodities. During the 1980s and early 1990s, however, intermodal providers developed high quality transportation packages equivalent to and even superior to the offerings of any individual mode. Intermodal transportation appears to be highly successful, and traffic growth trends are sharply upward, with 1994 being the latest in a series of record years for the industry. One interesting aspect of the shift to intermodalism is the corresponding impact on transportation safety. By definition, the use of intermodalism shifts traffic from the highway mode to rail over some portion of a distribution channel. Every highway trailer shifted to intermodal service represents a reduction in combination truck traffic on the highway system. In addition, intermodal services may capture new business before it ever reaches the highway system. Decreasing truck traffic on the highways should have a positive impact on highway safety. The goal of this study was to identify and, where possible, assess the potential implications of increased intermodal transportation on highway safety. Proponents of intermodalism frequently tout increased safety as one key benefit. The research attempts to quantify the effect of rail-highway intermodalism on truck VMT and the resulting effect on highway accidents. Impacts are calculated for the years 1992-1993 and, to aid policy decisions, for the year 2010. As background, the current intermodal transportation system is characterized. The research identifies intermodal transportation growth trends and forecasts future growth.
Abstract