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II. Background and Definitions – What is an Intermodal Connector?

A Short Legislative History

The Intermodal Transportation Efficiency Act of 1991 (ISTEA) created a new framework for addressing the nation's infrastructure into the 21st century. For the first time, an intermodal policy was established by law as a cornerstone of the Nation's federal surface transportation programs. ISTEA made it a national policy "to encourage and promote development of a national intermodal transportation system in the United States to move goods and people in an energy efficient manner, provide the foundation for improved productivity growth, strengthen the nation's ability to compete in the global economy and obtain the optimum yield from the nation's transportation resources."

ISTEA also called for the establishment of the National Highway System (NHS). In defining the NHS, the US Department of Transportation (USDOT) and the Federal Highway Administration (FHWA) recognized the crucial role played by intermodal connectors – those public highways which link the Nation's ports, rail and truck terminals airports and passenger transit terminals to the NHS. With active support from stakeholder organization such as the Intermodal Freight Transportation Coalition, the American Public Transit Association, the American Association of State Highway and Transportation Officials and the National Passenger Railroad Corporation, more than 2,000 miles of intermodal connector roadways were identified. The NHS Designation Act of 1995 directed the Secretary of Transportation to submit this list of intermodal connectors to Congress, and this list was subsequently presented in May of 1996.

In 1997, the NHS consisted of 156,986 miles, amounting to 4 percent of the total highway mileage. More significant than the number of miles is the fact that the designated NHS miles carry 1 trillion or 45 percent of the vehicle miles traveled (VMT). The roads in the NHS, therefore, represent the key arteries in the nation’s transportation system.

Congress enacted a second landmark Surface Transportation bill in May 1998 – the Transportation Equity Act for the 21st Century (TEA-21). Section 1106 (subsection d) of TEA-21 directed the Federal Highway Administration to conduct an intermodal freight connectors study. That subsection states:

  1. Report – not later than two years after the enactment of this Act, the Secretary shall -
    1. review the conditions and improvement made since the designation of the NHS connectors to the system that serve seaports, airports and other intermodal freight transportation facilities; and
    2. report to Congress the results of such review.
  2. Review – in preparing the Report, the Secretary shall review the connectors and identify projects carried out on those connectors that were intended to provide and improve service to an intermodal facility as referred to in the paragraph above and to facilitate the efficient movement of freight, including movement of freight between modes.
  3. Identification of Impediments – if the Secretary determines that on the basis of the review that there are impediments to improving the connectors serving intermodal facilities, the Secretary shall identify such impediments and make any appropriate recommendations as part of the Secretary's report to Congress under this subsection.

This TEA-21 reporting requirement provides a formal mechanism for USDOT to monitor intermodal connector performance and needs and to make recommendations to Congress regarding appropriate initiatives to assure adequate maintenance or expansion of connectors.

Defining an Intermodal Connector

The term "intermodal" refers to a transfer of a shipment from one transportation mode to another as the shipment moves from origin to destination. Defining an intermodal connector requires some additional elaboration due to the varying nature on type and capacity of intermodal connectors.

In April of 1995, FHWA issued Guidelines for Identifying National Highway System Connectors to Major Intermodal Terminals (HEP-12 from Thomas Ptak). This document indicated that NHS connectors must be public roads leading to major intermodal terminals and that those roads must have a critical bearing on the efficient operation of that facility. Intermodal terminals were defined as facilities which provide for the transfer of freight or passengers from one mode to another.

The primary criteria established by this document for defining an intermodal connector are based on annual passenger volumes or freight volumes or daily vehicular traffic on one or more of the principal routes which serve the facility. A secondary set of requirements include factors which underscore the importance of an intermodal facility within a specific state. The secondary criteria are specifically related to intermodal terminals that handle more than 20 percent of freight or passengers by mode within that state and also have significant highway interface. The subject intermodal terminals were anticipated to have been already identified by the state or metropolitan planning organization (MPO) as a major facility and targeted for major investments to handle expanded traffic.

Within the NHS, over 1,400 freight and passenger intermodal connectors were identified, including:

Connector Type Number
Public Transit Stations 389
Maritime Facilities 247
Airports 228
Truck/Rail Terminals 211
Intercity Bus Stations 99
Amtrak Stations 71
Pipeline/Truck Terminals 61
Ferry Terminals 59
Multi-modal Passenger Sites 42

This report focuses primarily on freight intermodal connectors. However, the performance benchmarks of transportation most often sought by freight users – reliability, transit time, efficiency and cost – are also the same characteristics sought by passengers. These performance factors also define many of the national security-related transportation needs.

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