Traffic congestion continues to worsen in American cities of all sizes, creating a $78 billion annual drain on the U.S. economy in the form of 4.2 billion lost hours and 2.9 billion gallons of wasted fuel—that's 105 million weeks of vacation and 58 fully-loaded supertankers.
These are among the key findings of the Texas Transportation Institute's 2007 Urban Mobility Report. Improvements to the methodology used to measure congestion nationwide have produced the most detailed picture yet of a problem that is growing worse in all 437 of the nation's urban areas. The current report is based on 2005 figures, the most recent year for which complete data was available.
"There is no 'magic' technology or solution on the horizon because there is no single cause of congestion," noted study co-author Tim Lomax, a research engineer at TTI. "The good news is that there are multiple strategies involving traffic operations and public transit available right now that if applied together, can lessen this problem."
The 2007 mobility report notes that congestion causes the average peak period traveler to spend an extra 38 hours of travel time and consume an additional 26 gallons of fuel, amounting to a cost of $710 per traveler. Along with expanding the estimates of the effect of congestion to all 437 U.S. urban areas, the study provides detailed information for 85 specific urban areas. The report also focuses on the problems presented by "irregular events"—crashes, stalled vehicles, work zones, weather problems and special events—that cause unreliable travel times and contribute significantly to the overall congestion problem. Worsening congestion, the study notes, is reflected in several ways:
- Trips take longer
- Congestion affects more of the day
- Congestion affects weekend travel and rural areas
- Congestion affects more personal trips and freight shipments
- Trip travel times increasingly are unreliable
Researchers spent two years revising the methodology using additional sources of traffic information, providing more—and higher quality—data on which to base the current study.
The report identifies multiple solutions to the congestion problem that, researchers say, must be used together to be effective. These include:
- Get as much service as possible from existing infrastructure
- Add road and transit system capacity in critical corridors
- Relieve chokepoints
- Change usage patterns
- Provide choices
- Diversify the development patterns
- Keep expectations realistic
"Congestion is a far more complex problem than is apparent at first glance," Lomax said. "The better the data we use to define the problem, the more successful we will be in addressing its root causes."