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A Desire Named Streetcar

Desperate to get citizens to move to the city and ride mass transportation, local governments embrace "traffic calming."

12:00 AM, Jun 23, 2006 • By RACHEL DICARLO
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PICTURE THE STANDARD CONGESTED AMERICAN CITY. Traffic backs up on city blocks each day during rush hour as cars creep along, catching every red light. A half-mile trip takes half-an-hour. The forced on-and-off of the gas and brake pedals spends more gas--and creates more pollution--than if cars were traveling at consistent speeds. Emergency vehicles have a difficult time cutting through the gridlock.

New data from the Texas Transportation Institute's 2005 mobility report helps illuminate the big picture: Since 1982, the annual average traffic delay per commuter has risen from 16 hours per year to 47 hours per year, with a total 3.7 billion hours lost every year in traffic jams. The number of urban areas with more than 20 hours of annual traffic delay has jumped from 5 to 51. And the daily rush hour periods, where the likelihood of encountering congestion is highest, have grown from an average of 4.5 hours to a 7.1 hour expanse, covering nearly a third of every day.

One cause of this gridlock is a practice that sprang from the increasingly powerful "smart growth" movement, and has been implemented in almost every American city and in many suburbs: traffic calming.

PROPONENTS OF TRAFFIC CALMING--mostly government planners--not only oppose new highway construction and, in some instances, highway maintenance, but want to reduce mobility by installing roadway barriers and traffic-slowing devices that clog up the roads. In other words, rather than alleviate congestion, traffic calming aims to induce it.

Why create congestion? The goal is to make driving as undesirable as possible, thereby discouraging sprawl and encouraging people to live in high-density areas, where they will either ride mass transportation or walk. Since most cities have trouble filling seats on their money-losing transit systems, traffic calming is also another way to try to make these systems more financially justifiable.

Traffic calming can be achieved in a number of ways. For instance, there are devices, such as speed bumps, small traffic circles, cul-de-sacs, and chicanes (which change a street's orientation from straight to winding), which help prevent cars from speeding through suburban neighborhoods. The most common practice is signal disruption--which guarantees that a driver who is obeying the speed limit will have to stop at almost every red light.

There are also choke points, which suddenly narrow a street to one travel lane; curb extensions, which eliminate right-turn lanes (so anyone who slows down to turn right slows down the cars behind her); median barriers, which reduce traffic volume (when located mid-block, median barriers do not help pedestrian safety, and, incidentally, have devastated some small roadside businesses by hindering access); orientation shifts, which change a one-way street into a two-way street; and vehicle exclusion lanes, among others. "Boulevarding" is the urban planning term used to describe when a variety of traffic-calming devices are used in conjunction with one another.

There's no firm data on how many cities and municipalities have invested in traffic calming, but it's difficult to find one that hasn't. (The FHWA has a partial list here.) Portland, Oregon, the birthplace of smart growth, spends over $2 million a year on traffic calming. Transportation expert Randal O'Toole notes in his book The Vanishing Automobile and Other Urban Myths that the Port of Portland, which helped fund the light rail line to the city's airport, claimed in a slideshow presentation that the key to successful airport rail is a "congested highway and roadway access system." Ten years ago, Portland predicted that its traffic-calming plan would triple local congestion, and concluded that "congestion signals positive urban development." The good news for the city council is that they're on target: In 2003 (the last year for which data is available), Portland's total delay had risen to 33,387,000 hours a year from 25,066,000 in 1996, according to the Texas Transportation Institute.

In Austin, to support a $15 million program that would change one-way streets into two-way streets, the city passed a "transportation hierarchy" resolution that would give first priority to pedestrians, second to public transit, third to bicycles, and last to private vehicles. Officials conceded that their plan would cause a 23 percent increase in traffic delays, but went ahead with it anyway. In 2002, San Jose spent $15.4 million converting 10 one-way streets into two-way streets.