How Urban Planning Can Improve Public Health
A growing movement looks to change development patterns — as a matter of public health.
You hardly need scientific research to pinpoint objectionable aspects of suburban sprawl. The big-box commercial jumble, the lifeless cul-de-sac subdivision, the traffic, the sameness — all are plain to see. Disagreeable qualities of half-empty downtowns and deteriorated city neighborhoods are equally visible. Still, people don't usually think that the things they find aesthetically objectionable about their neighborhoods might literally be making them sick.
Yet a growing mass of scientific evidence does indicate that how places are designed and built can cause and complicate grave health problems for individuals and whole populations. Depression — the clinical kind, not the aesthetic and cultural malaise that sends people vacationing to, say, Barcelona — is one. Studies show that depression correlates with the lack of access to green space, a plight of many inner-city residents; the physical isolation of suburbanites; and the immobility enforced on those who cannot drive but have no transportation alternative.
As for cars, they don't just spew pollution and trap people alone for wasted hours. They cause accident injuries and deaths. Moreover, unwalkable distances and the culture of automobility encourage sedentary habits, contributing to obesity and diabetes and other illnesses. Plowing up farmland for new subdivisions at the metropolitan edge not only diminishes local food supplies and reinforces industrial agriculture — with negative implications for nutrition and resource conservation — it also forces those who must "drive till they qualify" for housing to need a car for almost every household member. Those automobile costs, usually overlooked, have exacerbated soaring rates of foreclosure and suburban poverty, with unhealthful knock-on effects like stress, displacement and homelessness.
Many examples beyond these lead to a conclusion: The crucial questions about how we build focus less on aesthetics — important as that is to our well-being — than on public health, in its broadest sense.
City planning originated, around the turn of the last century, out of concerns over health problems created by filthy slums and industries. Then the fields of public health and planning came uncoupled. Public health took on a mainly biomedical focus on individual genetics, biology and behavior and how clinicians could affect those, and on a narrowly biological approach to epidemiology and evidence. Meanwhile the planning of built environments was hijacked by the car.
Now the fields of city planning and public health — pushed by economic crisis, climate change and green technology, among other factors — are converging again. This month, the Congress for the New Urbanism was set to hold its national convention in Atlanta; it was organized with help from the Centers for Disease Control and Prevention under the theme "New Urbanism: Rx for Healthy Places."
The convention is hardly the first effort to address the relationships between urban form and health. The World Health Organization's Healthy Cities movement was initiated in 1988; among other things, it encourages attention to health inequalities, participatory governance and the health considerations of economic and urban development. Some 1,200 European cities and many in Canada and Australia participate.
Back in the U.S., the Local Government Commission, an organization of elected and community leaders, government staff and planners and architects, adopted the Ahwahnee Principles for Resource-Efficient Communities in 1991. (The principles were named for the Yosemite National Park lodge where they were agreed to). The principles targeted the dysfunctional qualities of sprawl-pattern development; these ideas came to underlie the New Urbanism and Smart Growth movements. Meanwhile, The Robert Wood Johnson Foundation's Active Living Research program supports extensive research into the urban form/public health nexus. The CDC's Healthy Community Design initiative does the same.
Dr. Howard Frumkin, special assistant to the CDC director for climate change and health and co-author of Urban Sprawl and Public Health: Designing, Planning, and Building for Healthy Communities, actually calls the Congress for the New Urbanism "a public health group. By promoting walkability, mixed use, connectivity and civic space within communities, we know more and more, based on emerging evidence, that CNU is promoting public health."
To anyone who thinks the New Urbanism makes sense, research conclusions on how built environments affect health can seem self-evident. For example, studies have demonstrated that neighborhoods with shops, schools, libraries, workplaces and homes within easy walking distance tend to support higher levels of physical activity and have lower rates of obesity. Public transit use has a similar effect on activity and fatness. Research has indicated that exposure to nature may improve attention deficit hyperactivity disorder in children, and that people with access to parks exercise more.
Like, duh. "So much research is proving the obvious," says Ellen Dunham-Jones, associate professor of architecture and urban design at Georgia Tech and co-author of Retrofitting Suburbia: Urban Design Solutions for Redesigning Suburbs. "But once you get the numbers, you can hopefully get policy changes."
Research into the connection between urban life and public health is, however, also creating surprises. As an example, Dunham-Jones points to studies showing that compact communities reduce overall vehicular emissions — but that people who live next to highways and heavily trafficked arterial roads breathe in more emissions. "It may be healthy for the community at large but not for you," she says.
Pinning down the implications of such research subtleties remains a challenge. Frumkin identifies two still-poorly understood correlatives of built environment: "We have reason to believe that community design and building design have impacts both on mental health and on social capital. Social capital in turn is a very important determinant of overall health."
The plans for New Urbanism towns sometimes depict circles centered on retail areas, with radii labeled as the distance of a five- or 10-minute walk. But landscape architect Dee Merriam, a CDC community planner, says that even walkability, a seemingly unambiguous value, needs scrutiny. "The basic metric we've been using for urban design has been the automobile scale, and the walking scale is a totally different metric," she says. "What is the distance of a five-minute walk? It's probably very different for a young athlete than for an elderly woman or someone with toddlers."
Merriam says more investigation is also needed into green space, despite its known health connections; Dunham-Jones agrees, saying that research has raised complex questions about trade-offs. "Cities would prefer to have one big central park to maintain, than to have a whole lot of little parks. To really get people jogging, you need a big park. But to get little kids to go play, it's much better to have a lot of little parks," she says. "We can improve health by doing all sorts of things, but we're not at the point where we're maximizing dollar investment."
Some new efforts to find design solutions for health challenges involve food. Ideas range from turning abandoned space in declining neighborhoods into urban farms — projects like this are already under way in Detroit and elsewhere — and allotting space for community gardens in new developments. There is even a vision of "agriburbia," where entire neighborhoods are landscaped with orchards and cropland that could feed people in and beyond the development while providing local employment opportunities.
A recent design workshop addressed another piece of the healthy living puzzle: multigenerational or "lifelong" communities, where people can continue to live actively as they grow old. Specialists on aging, developers, planners and architects tried to envision the transformation of parts of metro Atlanta, reiterating the "must-haves" of New Urbanism — transit and walkability, mixed uses, multiple housing types — but describing how such elements could better accommodate the aging with, for example, shorter walking distances and shuttles to transit stops and shopping areas.
So the Congress for the New Urbanism, the CDC and others are taking important steps to address the cause-and-effect relationships of built environment and public health. But for towns and cities to be less damaging to health, those connections must become more universally acknowledged by health professionals, designers, planners and the decision-makers and developers for whom they work. Moreover, for the environment to support better health, public consciousness has to change. Individual choices will have to sustain healthier patterns of development, and political support will be needed, too, because some of the proposed changes in development demand big cultural shifts, particularly around auto use.
Many advocates say what's needed is a holistic view that considers health, the environment, social relations, political processes and the economy as part of the development process. Jason Corburn, associate professor of city and regional planning at University of California, Berkeley, and author of Toward the Healthy City: People, Places, and the Politics of Urban Planning, insists that architects and planners "need to recognize that they're part of governance," since a healthy city should invite open participation in its political processes, planning included. "This is not to say that design is not important," he says, but that it should be just one piece of thinking relationally about multiple influences upon health.
One tool that helps government officials identify such influences is the health impact assessment, an evaluation process similar to the environmental impact statement. Such health assessments are a relatively new phenomenon in the U.S., but several dozen have already been conducted, and the CDC is actively promoting their use. While there is a legal basis under environmental protection laws for evaluating health impacts of proposed projects, the officials responsible are often unfamiliar with the HIA concept, or can feel that it deals in types of evidence not traditionally considered valid in making development decisions.
But traditional thinking has produced the sickening built environments most Americans now inhabit. Even "progressive" ideas won't necessarily change them. For example, if everybody owned a car that drove 100 miles on a gallon of gas, the country would burn less oil — but sprawl would still be encouraged, and the population would continue to grow fatter, sicker and more isolated. It may be possible to influence the public to choose transit over cars; entrenched attitudes toward tobacco were changed after all. But to change transport habits, America needs to provide transit systems and walkable destinations as practical options, and that's where the architects and planners come in.