Justin Gillis
Hal Harvey
New York Times

SAN FRANCISCO — We might be living through a new age of miracles. Last month, Los Angeles decided against adding lanes to a freeway, an unexpected move in a city that has mistakenly thought for years that more lanes mean fewer traffic jams.

Shortly before that, Germany’s highest court ruled that diesel cars could be banned from city centers to clean up the air. Mind you, Germany is the land where diesel technology was invented — and Volkswagen, the world’s largest automobile maker, invested heavily in pushing the cars before it was caught lying about their emissions. After the court ruling, Volkswagen sputtered that it was “unable to comprehend” the decision.

These events occurred nearly 6,000 miles apart, in different political contexts, but they are connected. Both the public and a few of our bolder political leaders are waking up to the reality that we simply cannot keep jamming more cars into our cities.

A century of experience has taught us the folly of it. Three pathologies emerge. First, every car becomes the enemy of every other. The car you hate most is the one that’s right in front of you not moving. As cars pile in, journey times and pollution rise.

Second, after a certain point, more cars make the city a less congenial place for strollers, bicyclists and people who take public transit to their destinations. The cars push out frolicking kids, quiet afternoons reading on a bench and sidewalk cafes. So we give up our public space, our neighbor-to-neighbor conversations and ultimately our personal mobility for the next car, and the next one.

And then there is the odd fact, counterintuitive as it is, that building more roads does not really cure congestion and can even make it worse. The problem, as experts realized starting in the 1930s, is that as soon as you build a highway or add lanes to a freeway, cars show up to fill the available capacity. The phenomenon is so well understood that it has a name: induced traffic demand.

We asked Inrix, a company that collects sophisticated highway data, to analyze two relatively recent American freeway projects: the $1.6 billion expansion of Interstate 405 in Los Angeles and the $2.8 billion expansion that made the Katy Freeway in Houston, a section of Interstate 10, the widest in the world, at 26 lanes across.

After the I-405 expansion, the data shows, travel times worsened in both morning and evening rush hours. The Katy Freeway expansion yielded slightly better results, with the evening commute improving, though the effect was small in the westbound lanes. The morning commute got worse in both directions.

The people in charge of these projects will no doubt argue that with traffic growing overall, the freeways would be in even worse shape had they not been expanded. Still, these results are not much to show for such huge sums of public money. We think the billions going to these kinds of projects could be better spent maintaining the roads and bridges we already have.

The good news is that more and more cities are deciding to wrest control of their streets back from the tyranny of the automobile — and to put people, and other modes of transportation, on a par with the auto.
London now has 15 years of experience with a stiff “congestion charge” that discourages many drivers from entering the city center. In a virtuous cycle, the money goes to better public transit and more bike lanes. Early legislative discussions are underway about trying the same thing in Seattle and in some of California’s more congested cities. New York has just turned down such a plan for the second time in a decade, but the idea is not going to die — the city needs it too badly.

In the crowded cities of Asia, people are not allowed to get a car just because they want one. Shanghai residents must buy license plates that have gone for up to $13,000 at auction, and Beijing residents have to enter a lottery for a plate. Such measures might seem extreme, but they are sensible in a country that endured a 60-mile traffic jam in 2010 requiring 11 days to unsnarl.

As we write these words, we can sense the bile rising in some drivers. Americans have such a sense of entitlement about cars that any attempt to limit them can provoke a fight, as New York has discovered.
Yet the truth is that people who drive into a crowded city are imposing costs on others. They include not just reduced mobility for everyone and degraded public space, but serious health costs. Asthma attacks are set off by the tiny, invisible soot particles that cars emit. Recent research shows that a congestion charge in Stockholm reduced pollution and sharply cut asthma attacks in children.

The bottom line is that the decision to turn our public streets so completely over to the automobile, as sensible as it might have seemed decades ago, nearly wrecked the quality of life in our cities.

We are revealing no big secrets here. Urban planners have known all these things for decades. They have known that removing lanes to add bike paths and widen sidewalks can calm traffic, make a neighborhood more congenial — and, by the way, increase sales at businesses along that more pleasant street. They have known that imposing tolls with variable pricing can result in highway lanes that are rarely jammed.

But the planners had little clout as their bosses — city and state politicians — cowered before the demands of drivers. What we might be seeing, at last, is a shift in the public mood, a rising awareness that simply building more lanes is not the answer.

This interest in new ideas is an opening for mayors and governors. The smart ones are shaking off their obeisance to the automobile and thinking about how to create city streets and transport systems that work for everyone.

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Correction: April 25, 2018
This article has been revised to reflect the following correction: An earlier version of this article described the effects of an expansion of the Katy Freeway incorrectly. The evening commute improved in both directions, not just in the westbound lanes.
Justin Gillis is a contributing opinion writer. Hal Harvey is the chief executive of the research firm Energy Innovation.