Intermodal transportation is a factor permitting the integration of several transport networks towards more efficient forms. The above figure illustrates two alternatives to freight distribution. The first is a conventional point-to-point unimodal network where origins (points of production A, B, and C) are independently linked to destinations (points of consumption D, E, and F). In this case, two modes (road and rail) are used. Each connection is serviced by a separate contract. An issue concerns empty backhauls over long distances, particularly for trucks and the lower utilization level of truck and rail assets.
The second alternative involves the development of an integrated intermodal transport network using common load units (e.g. containers). Traffic converges at two transshipment points, rail terminals, where loads are consolidated. This results in higher load factors and higher frequency of services, especially between terminals. An important requirement is that the rail segment offers regularly scheduled services to which the feeders synchronize their activity. Under such circumstances, the efficiency of an intermodal network mainly resides in the transshipment capabilities of transport terminals.