Kenneth A. Small and
Chen Feng Ng
The tremendous expense required for new urban road capacity has led policy analysts and decision makers to despair of “building our way out of traffic congestion.” But there is another route involving highway design that is relatively unexplored: designing more compact roads.
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Kenneth A. Small and
Kurt Van Dender
Reducing US gasoline consumption might seem a straightforward task: just increase vehicle fuel efficiency, also known as miles per gallon (MPG). That, of course, is the principle behind the existing Corporate Average Fuel Economy (CAFE) standards.
But it’s not that simple. If MPG improves, the cost to drive a mile declines, so people drive more. Some critics have even argued that this “rebound” effect is so large that not much gasoline is saved, and other problems such as congestion are exacerbated. Is this right?
Kenneth A. Small
Observers of city life have long looked to mass transit to create urban vitality. Transit is supposed to promote a healthy high-density street life within economically vital business and retail districts, and to concentrate new developments into attractive patterns. Above all, it’s supposed to limit road congestion without resorting to ugly high-volume roads everywhere.
These goals have been frustrated by the limited ability of mass transit to attract travelers out of automobiles and by the enormous expense of building and operating mass transit. While many recently built transit systems have achieved some desirable effects, none have seriously lessened traffic congestion. Furthermore, few cities have been able to afford a system extensive enough to make more than a small change in urban form; and the share of trips by mass transit continues to fall virtually everywhere.
Kenneth A. Small
Seeking ways to ease highway financing and alleviate traffic congestion, policy makers have put toll roads on the national agenda. The public is skeptical of the idea, to say the least. So the federal government has been sponsoring demonstration projects, both to gain practical experience and to increase public familiarity with road-pricing concepts and the ways they work.
Although most of the demonstrations are merely studies, two are currently operating on real roads in California. They show that the hardware and software work well, that transactions and enforcement are manageable, and that drivers easily adjust to pricing.
One project, the SR91 express lanes in Orange County, is a privately financed ten-mile roadway that parallels the Riverside Freeway (SR91), a notorious bottleneck. Drivers using the new roadway pay electronically according to a fee schedule that varies by time of day and day of week. Three-person carpools use the lanes at a discount. When the new lanes opened, typical peak-hour delays on the original lanes on this ten-mile section fell from over thirty minutes to less than ten minutes.
Kenneth A. Small
Driven by problems of traffic congestion, U.S. policy toward urban highways has lurched over several decades from highway building to high-occupancy-vehicle lanes to travel demand management. Yet congestion has worsened, and there is scant evidence that these policies have had any appreciable effect on it. As financial straits tighten, policy analysts are looking for new solutions.
Meanwhile, economists have been polishing up a long-standing proposal known as congestion pricing. Under this policy, drivers would have to pay a very high fee for driving on the most popular roads during peak hours. We already expect to pay top price for long-distance phone calls during business hours, and many of us wait for discounts at night. But can the same concept work for highways?