A few years ago, a strange thing happened: Americans started driving less.
How strange was it? For 60 years, up until 2005, the number of miles driven on America's roads increased by an average of 3.7 percent per year -- that's more than twice as fast as population growth. Today, however, Americans are driving just about as much as we did six years ago overall. And on a per-capita basis, as researchers from the Brookings Institution have pointed out, the number of miles driven actually peaked a decade ago.
As President Obama and Congress debate infrastructure investments -- both as part of the president's jobs strategy and the ongoing debate over re-authorization of the transportation bill -- it is important to know whether the trend away from ever-increasing amounts of driving is real or a temporary blip. If the trend is real, it would suggest that our transportation policies -- the broad outlines of which were established when "Leave It to Beaver" was on TV and America still produced most of its own oil -- need a serious rewrite for the 21st century.
What do we know? First, we know that driving has fallen fastest among young Americans -- precisely the people who will be most impacted by today's transportation infrastructure choices. According to the National Household Travel Survey, the average number of miles driven by licensed drivers aged 20 to 34 fell by 12 percent between the recession years of 2001 and 2009. Meanwhile, the percentage of 19-year-olds with a driver's license has plummeted from 92 percent in 1978 to 77 percent in 2008.
Some cultural observers suggest that these trends are part of a larger generational shift -- one in which digital connectivity trumps horsepower, and iPads and Androids take the place of an earlier generation's '57 Chevys as symbols of consumer aspiration and freedom.
Other factors are at work as well. The easy mortgage credit that once financed the construction of McMansions in auto-oriented exurbs is gone. Consumer tastes in housing are shifting toward walkable neighborhoods in proximity to urban amenities. A recent report by PricewaterhouseCoopers and the Urban Land Institute projects that, "24-hour neighborhoods in cities and urbanizing suburban nodes [will] become more desirable locations," while "fringe suburban subdivisions [will] lose some appeal."
The giant baby boom generation is now moving into retirement -- a period in life when driving typically decreases. Gasoline prices aren't going down any time soon. And more Americans continue to look for opportunities to walk or bike where they need to go -- both to save money and to enjoy better health.
Temporary factors, such as the recession and spikes in gasoline prices, have certainly played a role in the reduction in driving. But an accumulation of evidence suggests that -- at minimum -- the days of rapid, steady growth in vehicle travel are over.
Why then is Washington arguing about how much to spend building our grandfather's transportation network? The main question shouldn't be whether we spend too much or too little on those programs. Instead, we should ask why we continue to spend vast sums on building new highway capacity -- especially when there are far more productive ways to invest that money.
Fixing our existing roads, bridges and transit infrastructure is a good place to start. Yet, federal and state policies often serve to incentivize the construction of new highway capacity over the less-glamorous task of taking care of what we have.
At the same time, Americans are hungering for more and better transportation choices. Cities and states have proposals for new transit lines, passenger rail service, bike lanes and sidewalks that are stuck on the drawing board for lack of funds. And if the objective is job creation, there is really no contest: a recent report by Smart Growth America found that public transportation projects funded under the American Recovery and Reinvestment Act created 70 percent more jobs per dollar than highway projects funded under the law.
America's transportation needs and desires are changing. If the president and Congress want to get the most out of our transportation investments, they must discard outmoded assumptions and make decisions based on the real needs of Americans in the 21st century.
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