Reason Foundation
Mobility Project

Building Roads to Reduce Traffic Congestion in America's Cities:
How Much and at What Cost?
By David T. Hartgen, Ph.D., P.E. and M. Gregory Fields
Project Director: Robert W. Poole, Jr.

How bad is your commute going to get? Twenty-five years from now, Los Angeles, home to the nation's worst traffic today, will still have the nation's worst delays, with a trip during peak hours taking nearly twice as long as it would during off-peak times.

But by 2030, drivers in 11 other major cities – Atlanta, Baltimore, Chicago, Denver, Las Vegas, Miami, Minneapolis/St. Paul, Portland, San Francisco-Oakland, Seattle-Tacoma, and Washington, D.C. - will all be sitting in daily traffic jams worse than the infamous traffic jams that plague Los Angeles today, according to a Reason Foundation study.

Across the country, the study finds that traffic delays in large areas will increase 65 percent and the number of congested lane-miles on urban roads will rise by over 50 percent in the next 25 years. To relieve this severe congestion the nation's freeways will need 104,000 additional lane-miles of capacity (about 6 percent of current lane-miles) at a cost of $533 billion over 25 years.

» Press Release
» List of Most Congested Cities
» List of Most Congested States
» USA Today Story

Interactive Maps

» Most Congested Cities in America in 2030
» Ranking the States by Congestion and Costs to Reduce Traffic

Full Study

» Building Roads to Reduce Traffic Congestion in America's Cities: How Much and at What Cost? (.pdf)

State-by-State Examination

Shows how congested each state and its major cities will be in 2030. Details how many lane miles are needed and at what cost. Projects the number of hours we can avoid sitting in traffic each year by relieving congestion.

» State-by-State Analysis of Future Congestion and Capacity Needs (.pdf)

Appendices to Full Study

Appendix A (.pdf)
Appendix B: Detailed Methodology (.pdf)
Appendix C: Detailed City-by-City Data (MS Excel)
Appendix D: State Information (MS Excel)
Appendix E: State Information (MS Excel)
Appendix F: State Information, Rural (MS Excel)
Appendix G: Regional Urban Maps of Travel Time Indices (.pdf)
Appendix H: Risk Analysis of the Costs to Relieve Congestion (.pdf)
Appendix I: References (.pdf)

Media Contact
Chris Mitchell
(310) 367-6109

Additional Resources
» Reason Foundation's Mobility Project Main Page
» Reason Foundation's Transportation Research and Commentary

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