Oct. 31 2014
Engineering an ambitious traffic policy

Zero is not a number that gets thrown around very often in public health. Even the most ambitious efforts shy away from it. Yet that is the goal of Vision Zero, New York City’s new, Swedish-imported traffic program: to have not a single traffic death on city streets by the year 2024.


"No level of fatality on city streets should be considered inevitable and acceptable," said former acting U.S. Surgeon General Kenneth Moritsugu, summing up the philosophy behind the program. Moritsugu spoke at a Columbia University Seminar on the new traffic policy, which was sponsored by Columbia University’s Center for Injury Epidemiology and Prevention at the Mailman School of Public Health. The event brought together representatives of some of the disparate agencies and organizations charged with carrying out Vision Zero: the New York City Departments of Health and of Transportation, the New York City Police Department, and the New York City Council, to share research and strategize about the path to zero.

According to Guohua Li, Finster Professor of Anesthesiology and Epidemiology at the Mailman School, the same principles epidemiologists draw on to eliminate diseases from a population can be applied to traffic injuries: reducing the "exposure"—in this case the traffic, reducing the occurrence of injury when one is exposed, and reducing the likelihood an injury will result in death or serious disability.

Safe Routes to School

Over one-third of children in three "low walkability" zip codes do not walk or bike to school, even though 40 percent of them live within five blocks from school and 70 percent live within 20 blocks, according to a study by Philip Noyes, the director of research, evaluation, and planning in the Department of Health’s Brooklyn District Public Health Office. Less than half of students think it is safe to walk, and only one-third think it’s safe to bike.

And there is still a wide disparity in neighborhoods. While some of the city’s well-off areas enjoy walkable conditions—lower and mid-Manhattan, west Brooklyn, and west Queens; Staten Island and eastern Queens are far less pedestrian friendly, according to Jennifer Norton of the Department of Health’s Bureau of Environmental Disease and Injury Prevention.

"If we don’t have that commitment to changing all neighborhoods and not just responding to those neighborhoods that are able to self-advocate, we’ll likely see that gap maintained or possibly increase," said Noyes.

Another area where improvement is possible is calming New York City’s aggressive and chaotic traffic stew of impatient drivers, bikers, and pedestrians. So-called "traffic calming" measures, which aim to make the streets safer for pedestrians, include lowering the speed limit, narrowing streets, adding speed bumps, new traffic and pedestrian signals, and high visibility crosswalks, according to Charles DiMaggio, associate professor of Epidemiology at Mailman.

A Global Vision

Reducing traffic injuries and deaths is not only a city goal but also a national and international priority.

Traffic injuries are the eighth leading cause of death around the world and could become the fifth by the year 2030. In many fast-developing middle-income countries, motorized vehicles flood the streets while infrastructure improvements lag.

Reducing injury mortality and morbidity from motor vehicle crashes is one of the U.S. Centers for Disease Control and Prevention’s "winnable battles." The agency is focused on increasing use of seatbelts and childhood protection seats, reducing alcohol impaired driving, and preventing injuries among high-risk populations like teenagers, the elderly, and Native Americans, according to Arlene Greenspan, associate director for science at the CDC’s National Center for Injury Prevention and Control.

Participants agreed that Vision Zero is a "gift" as DiMaggio put it, one that will benefit from population health insight. "The public health approach and Vision Zero are perfectly aligned," said Moritsugu.

Read more about Vision Zero in the 2 X 2 Project's full story here.

By Elaine Meyer,
Department of Epidemiology