Background: At a time when the physical capacity of the nation's highways, railroads, airports, and waterways has stabilized, freight demand continues to grow. One recent forecast, for example, indicated that annual tons of freight transported in the United States would be likely to increase by 21 percent and commercial truck-miles by 29 percent in the next decade. At the same time, passenger traffic, which often competes with freight for available capacity, is growing.

In spite of projected increases in demand, capacity expansion in many parts of the system has slowed since the 1970s. In the post-World War II period, the nation rapidly expanded its highway, airport, and port capacity. Today, the intercity network of highways is growing at less than 0.5 percent per year. Future federal capital funding for roads, airports, and waterways is projected to decline in real dollars. These trends imply that capacity constraints may degrade the nation's freight efficiency by early in the next century.

In the rail system, traffic on some corridors may be reaching capacity limits. Port officials are concerned about bottlenecks at the ports that are to be served by the next generation of "megaships" and about the adequacy of road and rail access to ports. Barge operators express concern about investment needs to maintain and upgrade locks where congestion is severe. Finally, forecasts show a tripling of air freight volume in the next 20 years, suggesting increasing conflict between passengers and freight at airports.

Objective: It is premature to predict a crisis, as substantial levels of investment are expected in some components of the freight system in the next decade and the system has flexibility to adapt to changing circumstances and to make resources go further through productivity improvements. However, responsible management of the public sector's facilities requires a long-term planning perspective.

Policy options for coping with capacity constraints include investment, pricing, regulatory, technological, and other approaches. The options are complex and controversial. Expansion of physical highway capacity is constrained by available revenues, environmental restrictions, and lack of public support. Moreover, major additions to capacity require 10 years or more from the time a project is approved until it is in place. Pricing of facilities to manage demand is very controversial. Increasing trucking productivity by allowing larger vehicles is resisted by motorist, safety, and railroad interests. Increasing capacity at ports and rail yards to allow more freight to be moved by rail is difficult because of dense development around these facilities, local resistance to increased freight traffic, and lack of politically acceptable funding mechanisms. Some technology "fixes," such as advances in intelligent transportation systems or in train control, may help, but the benefits and feasibility of widespread implementation are uncertain.


Tasks: The research is being conducted as a TRB policy study following the procedures of the NRC. TRB has formed a committee with expertise in economic modeling, logistics, freight carriage, administration of public-sector transportation programs, and public policy. The committee is developing four case studies, of particular freight problems or projects that relate to long-term capacity issues, as an approach to understanding the nature of supply problems and project-level decision making. Case studies include a port access project, an Interstate highway expansion program, public-private cooperation in statewide freight planning, and an inland waterways project. The committee also has conducted a series of interviews with industry leaders to obtain views from diverse viewpoints on freight capacity problems and needs. It is examining historical trends and projections of freight traffic and system performance.

At its March 2000 meeting, the committee began to develop its conclusions and recommendations, which will be in four areas: interpretation of the significance of freight market trends and assessment of the future adequacy of freight capacity; definition of principles to guide public decisions affecting freight capacity; recommendations on immediate policy questions that affect freight capacity; and long-term policy proposals, possibly including proposals that represent more pronounced departures from established practice.

Status: The final report has been completed and published.

Product Availability: The publication entitled, TRB Special Report 271: Freight Capacity for the 21st Century, has been released and is available on the TRB website at https://onlinepubs.trb.org/onlinepubs/sr/sr271.pdf.