The Corridor as a System

A transportation corridor is a largely linear geographic band in or near a population center and all the elements of surface transportation it contains, including freeways, city streets, bus and rail lines, waterways, bicycle and pedestrian pathways, and so on. The figure below illustrates a corridor with:
  • a freeway (in black) with ramp metering lights
  • city arterial streets (in blue) with traffic signals at the intersections
  • bus service on the arterials
  • rail transit (in red) with parking at the station

Traditionally, individual transportation elements were managed separately (such as adjusting freeway ramp metering). While this can produce isolated improvements, it does not consider the unused capacity of other corridor elements or the potential negative effects the change could have. For example, directing traffic off the freeway to circumvent an accident could flood arterial streets with traffic they cannot absorb, thus creating additional congestion.

 By treating the corridor as an overall system, however, it becomes possible to:
  • take all elements in a corridor into account
  • consider the capabilities and interdependencies of all elements
  • more efficiently use the corridor's existing capacities, making transportation investments go farther
  • coordinate and manage the corridor's elements as an integrated system

This is the purpose of Integrated Corridor Management and the goal of the Connected Corridors program.

Redefining the "System"

Including both institutional and technical dimensions allows us to broaden the definition of an ICM "system." Not simply a piece of technology, the system is considered a total entity made up of people, organizations, hardware, and software, as illustrated below. All these components must work together to achieve effective Integrated Corridor Management.