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1.0 Introduction

1.1 The Problem of Congestion

The last several decades have witnessed steady growth in the demand for freight transportation in the United States, driven by economic expansion and global trade. But today, the nation is entering the early stages of a capacity crisis. Freight transportation capacity is expanding too slowly to keep up with demand, and the freight productivity improvements gained though investment in the Interstate highway system and economic deregulation of the freight transportation industry in the 1980s are showing diminishing returns.

The effects of growing demand and limited capacity are felt as congestion, upward pressure on freight transportation prices, and less reliable trip times as freight carriers struggle to meet delivery windows. Higher transportation prices and lower reliability can mean increased supply costs for manufacturers, higher import prices, and a need for businesses to hold more expensive inventory to prevent stock outs. The effect on individual shipments and transactions is usually modest, but over time the costs can add up to a higher cost of doing business for firms, a higher cost of living for consumers, and a less productive and competitive economy.

Freight congestion problems are most apparent at bottlenecks on highways: specific physical locations on highways that routinely experience recurring congestion and traffic backups because traffic volumes exceed highway capacity. Bottlenecks on highways that serve high volumes of trucks are "freight bottlenecks." They are found on highways serving major international gateways like the Ports of Los Angeles and Long Beach, at major domestic freight hubs like Chicago, and in major urban areas where transcontinental freight lanes intersect congested urban freight routes.

Freight bottlenecks are a problem today because they delay large numbers of truck freight shipments. They will become increasingly problematic in the future as the U.S. economy grows and generates more demand for truck freight shipments. If the U.S. economy grows at a conservative annual rate of 2.5 to 3 percent over the next 20 years, domestic freight tonnage will almost double and the volume of freight moving through the largest international gateways may triple or quadruple. Without new strategies to increase capacity, congestion at freight bottlenecks on highways may impose an unacceptably high cost on the nation's economy and productivity.

1.2 The Federal Role

The Intermodal Surface Transportation Efficiency Act (ISTEA) and the Transportation Equity Act for the 21st Century (TEA 21) called upon the Federal government to develop a "National Intermodal Transportation System that is economically efficient and environmentally sound, provides the foundation for the Nation to compete in the global economy, and will move people and goods in an energy efficient manner…." 1 The recently enacted Safe, Accountable, Flexible, Efficient Transportation Equity Act: Legacy for Users (SAFETEA LU) reaffirms the need for Federal government leadership in freight transportation. Therefore, the U.S. Department of Transportation (DOT) will have an increasing responsibility to develop and shape freight transportation policy options and programs. To do so, the Federal Highway Administration (FHWA), which oversees a National Highway System that carries 71 percent of all freight tonnage, must build a new generation of freight planning and policy analysis tools. The FHWA must be able to understand freight patterns, anticipate changes, and estimate the benefits and costs of capital investment, policy, and regulatory strategies to improve freight transportation.

The FHWA Office of Policy has begun to build these capabilities under is its "Strategic Analysis of Multimodal Transportation Policy Options" initiative. This initiative will develop a multimodal freight transportation network model and benefit/cost analysis tools that can evaluate capital, policy, and regulatory strategies for freight transportation.

1.3 The Objective of This Paper

This white paper is an initial effort to identify and quantify, on an national basis, highway bottlenecks that delay trucks and increase costs to businesses and consumers. The paper is the first to look specifically at the impacts and costs of highway bottlenecks on truck freight shipments. The paper builds on three streams of research:

The paper sets up a typology for highway freight bottlenecks, identifies an initial list of significant bottlenecks, and recommends ways to improve the analysis of bottlenecks and use the information in developing policies, programs, and projects to improve freight flows. The methods, findings, conclusions, and recommendations of the white paper are organized and presented as follows:

The paper has four appendices.

1 See Section 2, Declaration of Policy, "Intermodal Surface Transportation Efficiency Act of 1991," H.R. 2950 (Enrolled Bill), Public Law 102 240, 105 Stat. 1914.
2 "Unclogging America's Arteries: Effective Relief for Highway Bottlenecks—1999-2004." Prepared by Cambridge Systematics, Inc. for the American Highway Users Alliance, Washington, D.C., 2004. See
3 See
4 See David Schrank and Tim Lomax, 2003 Annual Urban Mobility Report, Texas Transportation Institute, available at
5 See "Traffic Congestion and Reliability: Linking Solutions to Problems," prepared by Cambridge Systematics, Inc. for the Federal Highway Administration, Office of Operations, Washington, D.C., July 2004. See

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