By 2030, drivers in 11 metro areas-Atlanta; Baltimore; Chicago; Denver; Las Vegas; Miami; Minneapolis/St. Paul; Portland, Ore.; San Francisco-Oakland; Seattle-Tacoma; and Washington, D.C.-will be stuck in daily traffic jams that are as bad as or worse than today’s infamous bottlenecks in Los Angeles, according to a new Reason Foundation study. In those cities, it will take at least 75 percent longer to make a trip during peak hours than during off-peak periods. The Reason Foundation, a nonprofit think tank, predicts that Los Angeles will continue to have the longest delays, with trips during peak hours taking nearly twice as long as they do when roads are free-flowing.

Today, only four cities (Los Angeles, Chicago, San Francisco, and Washington, D.C.) experience travel-time delays of even 50 percent. But, because road capacity is failing to keep up with demand and population growth, the Reason study predicts that 30 cities will be experiencing daily delays that make rush hour trips 50 percent longer than off-peak journeys. And even in smaller cities, traffic congestion will worsen substantially during the next two decades. Traffic delays will increase 65 percent and the number of congested lane-miles on urban roads will rise by 50 percent over the next 25 years, according to the study.

U.S. freeways and arterials need 104,000 additional lane-miles of capacity (about 6 percent more than current lane-miles) to prevent or relieve this severe congestion, at a total cost of $533 billion over 25 years, according to the Reason report. The $533 billion price tag breaks down to slightly more than $21 billion per year, which represents 10 percent to 15 percent of the money that is projected to be spent as part of the highway program over the next 25 years. It is also just 28 percent of planned spending in existing long-range plans of major urban transportation agencies. And it works out to about $2.76 per hour of delay saved, just 1/10 the cost of federally funded transit lines, the Reason study calculated.

"Contrary to conventional wisdom, it is possible for America to ‘build out’ of severe congestion, and it is relatively inexpensive to do so," said David Hartgen, the study’s lead author and a professor of transportation studies at the University of North Carolina at Charlotte. "The bottom line is that if we want to reduce congestion, or even simply maintain our current levels of traffic, we will need to seriously reexamine what is presently planned for our roads."

"We will be spending billions on transportation projects in the coming years, but after population growth and increased truck traffic, our congestion will actually be far worse, if we spend those billions as now planned," said Robert Poole, director of transportation at the Reason Foundation and the study’s project director. "We must prioritize and focus our transportation funding where it can do the most good. We know the vast majority of Americans need to drive cars and that trucks haul 80 to 90 percent of our economy’s goods. Unless we take significant action to add capacity where commuters have shown they want and need it, our economy and quality of life will take a pounding from congestion."

The study highlights that instead of adding capacity on the roads and freeways, planners in a number of metro areas are hoping to get people to shift behavior and leave their cars behind. In highly decentralized Los Angeles, where just 4.8 percent of people use transit to commute, more than half of the long-range plan money-$66.9 billion-is being spent on transit. The transit spending is nearly identical to the money ($67.7 billion) that the study claims is needed to relieve the area’s severe congestion. Likewise, cities such as San Jose and Salt Lake City, where transit’s share of commuting is less than 3 percent, are committing more than half of their long-range transportation funds to transit.

"Increased capacity is the most important need. Toll roads and variable-priced lanes, traffic signal optimization, improved accident management, and-where justified by ridership numbers-better transit, should all be part of our transportation solution mix," Hartgen added. "It is vital that all transportation projects be evaluated on cost effectiveness and hours of delay saved."

The Reason Foundation study used national congestion figures, detailed transportation data provided by 32 cities, and computer modeling to calculate traffic statistics for 403 U.S. cities. The full study, Building Roads to Reduce Traffic Congestion in America’s Cities: How Much and at What Cost?, is available online. A complete state-by-state breakdown of information on more than 400 U.S. cities, including interactive maps, projected congestion, lane-miles needed, and construction costs, can be found here.  Reason’s transportation research and commentary is available at

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