The Kind of Cities We Need
Urban growth is not driven only by people’s demands—what we want—it is also influenced by involuntary needs. The dense, walled European towns of the Middle Ages, for example, were the result of their inhabitants’ need to seek common safety behind protective walls, not of a desire for a compact way of life. American settlers located towns near safe anchorages because they depended on water transport, not because they wanted a marine view. The unprecedented growth of industrial cities in the nineteenth century, which so dismayed Ebenezer Howard, was produced by the need for large pools of labor of the urban factories that had replaced rural farms as the chief source of employment.
Transportation remains one of the most important external forces that influence the shape of cities. In the preindustrial world, the size and density of cities was determined by the relatively short distance that people could travel on foot from their homes to their workplaces; for the wealthy, who could afford horses and carriages, this distance was somewhat greater. Starting in the nineteenth century, horse-drawn omnibuses, electric trolleys, railroads, and subways enabled cities to spread out and encouraged the growth of residential suburbs at the periphery. In the twentieth century, automobiles doubled and tripled commuting distances, allowing far-out exurban development to flourish. Air travel, too, influenced urbanization by making relatively remote cities more accessible.
Transportation accounts for more than two-thirds of American oil consumption. The average global price of crude oil during the post–Second World War period was $27 a barrel (in 2008 dollars). After a low of $16 at the beginning of 1999, the price rose to $50 in 2005, and passed $145 in the summer of 2008. The chief reasons for the price increase were greater demand caused by China’s and India’s industrial booms, uncertainty about future supplies, and the inability—or unwillingness—of suppliers and governments to increase production. Oil prices were further increased to American consumers since crude oil was priced in U.S. dollars, and in 2008 the dollar was weak compared to other major currencies. Oil prices have spiked before—in the 1970s, when the Organization of Petroleum Exporting Countries imposed an embargo following the Arab-Israeli war, and in the 1980s, during the Iran-Iraq war. The spike of 2008 did not last long, and prices have since fallen, but the immediate impact on the economy—and on people’s behavior—offers a revealing portent of things to come. Sooner or later, we will be paying more for gas again.
At first glance, higher energy prices should benefit cities, especially cities with mass transit, since with higher oil prices the cost of traveling by bus or subway increases much more slowly than the cost of operating a private automobile. The 2008 gas-price spike, for example, produced an instant change as mass-transit ridership rates rose 5 to 15 percent, not only in traditionally transit-oriented cities such as New York, Chicago, and Boston, but also in cities with new transit systems, such as San Francisco, Denver, Minneapolis, Seattle, and Dallas–Fort Worth. Bus and train lines in Houston, Nashville, Salt Lake City, and Charlotte, North Carolina, also experienced increases.1 Cities have several transportation advantages. Since they are more compact than suburbs, walking and bicycling are feasible, as is using scooters or micro-cars. Higher population densities enable large cities to offer a greater variety of stores, services, and cultural amenities within relatively small areas, further minimizing local travel. Lastly, urban housing, especially in the centers of older cities, tends to be smaller, more compact, and more closely packed—row houses, walk-up flats, and apartment buildings—and hence produces lower heating and air-conditioning loads than large, freestanding suburban houses.
High gas prices also represent an opportunity for cities to increase their share of employment, since for the first time in a long time, size and density would be competitive advantages. But a major snag is that most cities do not currently have a wide range of employment opportunities. The high-tech jobs in the San Francisco region, for example, tend to be suburban; the same is true in Seattle and Boston. Moreover, for corporate employers, large cities currently have a number of significant disincentives: faltering school systems, high tax burdens, unwieldy municipal bureaucracies, poor services, and unresponsive governments.
For one group, job opportunities are not an issue: retirees. While downtown multifamily housing has traditionally targeted high-income empty nesters, more demand for downtown living may now come from middle-income, aging suburban homeowners who are nervous about rising gas and heating-oil prices. While the majority of lifelong suburbanites are unlikely to suddenly become urbanites, some suburbanites on fixed incomes would see city living as a hedge against rising prices.
Higher energy costs also produce negative effects on cities. Part of the downtown housing boom of the last two decades was fueled by so-called reverse commuters, people whose jobs were in the suburbs but who lived in the city. Reverse commuting has been the fastest growing segment of all commuting trips, especially in large cites, although suburb-to-suburb commuting still constitutes the majority of all commuting trips.2 The easiest way for reverse commuters to save money is to move closer to their jobs—that is, back to the suburbs. (Some evidence suggests that this occurred in 1981, the last time gas prices spiked.)
Rising prices for gas, as well as for other energy-related sectors (home heating, food, services), would likely lead to reductions in discretionary spending on recreation and tourism, which are both economic mainstays of large cities. A reduction in the number of tourists, museum visitors, and theatergoers would hit cities hard. Higher travel costs would first affect tourist cities such as Orlando, Miami, Las Vegas, and San Francisco, which depend on distant visitors. Cutbacks on less profitable schedules by struggling airlines are already reducing service to smaller cities, which will affect their rates of growth. Lastly, rising air travel costs will reduce nonessential business travel, such as annual meetings and conventions, both key urban industries. So, whatever advantages accrue to cities as a result of new residents, these are likely to be offset by losses in short-term visitors.
It is too soon to judge the effect of the current recession on cities, but it is likely to have effects similar to those of high gas prices. Cities are already feeling the pinch of less leisure and business travel, for example, with a resulting drop-off in hotel bookings and restaurant business. Residential construction has halted in cities as well as suburbs, and the downtown real estate boom that many cities experienced in the last two decades has halted with it. Shrinking tax bases are putting a severe strain on municipal services, and with reduced services downtowns are less attractive places to live. During the current recession, the downtown populations of many cities will likely shrink, as they did during the slowdown of 1970–90.
Higher oil prices would obviously affect suburbs and dispersed cities, which depend on automobiles. Over time, suburban drivers could be expected to make more use of car pools, and mass transit where that is available, with a demand for more bus routes, at least in denser suburbs. Transit-oriented communities would have an advantage, and densities would rise in suburban town centers. Since suburbs are built to relatively low densities, even modest densification would go a long way to reduce car dependency, at least for local trips. However, the main change will likely be behavioral. When oil hit $60 a barrel, personal expenditures on gasoline actually fell slightly in real terms, showing how quickly consumers could change their driving habits and substitute smaller for larger cars (in the first half of 2008, sales of large pickup trucks and sport utility vehicles dropped 25 and 30 percent respectively).3 Even when gas prices are no longer high, this preference may continue. According to the Department of Transportation, the top ten vehicles purchased under the federal Cash for Clunkers program, which encouraged owners to trade in old cars for more fuel-efficient models, were all subcompacts, compacts, and mini-SUVs.4
One would expect the demand for denser, walkable suburban communities to increase. This would help not only new developments but also older, inner suburbs, which tend to be more compact. Older suburbs, which have seen deterioration of their housing stock and lower real estate values, might attract new residents as higher gas prices cause home buyers to consider commuting time, access to mass transit, density, and closeness to urban centers. The new exurbs that have recently sprung up at the far edges of metropolitan areas may fare less well. Exurban home buyers trade long commuting times for cheaper housing, and when long commutes become more expensive, the trade-off will be less attractive.
Since the majority of Americans now live and work in the suburbs, the market would likely adjust to high gas prices not only by moving additional jobs and retail closer to suburban residents, but also by developing more efficient heating and air-conditioning systems and, of course, producing smaller, more energy-efficient cars, as well as vehicles that run on alternative fuels such as ethanol blends and natural gas. So far, only one manufacturer produces a natural-gas vehicle, and filling stations are rare, but in many ways natural gas represents the simplest technological alternative. All-electric cars still await improvements in battery technology; in the meantime electric-gas hybrids are an option. In mid-2008, Toyota announced that it sold more than 1 million Prius hybrids, and Honda has just unveiled its own model. Honda also recently introduced a hydrogen fuel-cell car, the FCX Clarity, which is said to be twice as energy efficient as a gas-electric hybrid, and three times more than a standard gasoline-powered car. While the FCX remains prohibitively expensive, the promise of alternative transportation is real. If automobile manufacturers can produce an affordable car that does not require gasoline—or uses considerably less—the suburbs would get a new lease on life.
Natural-gas vehicles significantly reduce environmentally harmful carbon monoxide emissions and also cut down on emissions of various oxides of nitrogen and reactive hydrocarbons. Hydrogen fuel-cell cars emit only water and none of the gases believed to induce global warming. Electric vehicles produce no emissions at all (although electricity generated by fuel-powered power plants does). So, if there is a silver lining to the high-oil-price cloud, it is that most energy-conserving or energy-substituting strategies—such as driving smaller and more fuel-efficient cars, driving less, using alternative transportation and mass transit, densifying neighborhoods, and building more energy-efficient houses—also improve the global environment.
In 1950, global emissions of carbon dioxide amounted to 6 billion tons a year. Thanks to population growth, urbanization, the expansion of wealth, and massive industrialization around the world, by 2008 emissions increased fivefold to 30 billion tons a year. If nothing is done to reduce emissions, by 2058 they will be 60 billion tons a year. Thus, to control global warming, whose effects are already beginning to be felt, it will be necessary to take drastic measures just to stay at the present level of emissions, never mind actually making real reductions. For example, to reduce the number of coal-fired generating plants, nuclear capacity in the United States will have to be doubled. To reduce car emissions, Americans will either have to drive half as many miles per year, or cars will have to be twice as efficient (although some evidence suggests that owning more efficient cars actually increases the amount that people drive).
Buildings use a lot of energy. The construction and operation of residential and commercial buildings consume as much as 40 percent of the energy used in the United States today, so reducing global emissions requires changing the way that buildings are designed and built. So-called green buildings incorporate a variety of devices and techniques. Energy consumption is reduced by using highly transparent glass, which decreases artificial illumination and reduces heat loads due to electric lights. Coatings on glass, or shading devices, prevent heat-causing solar radiation from entering buildings. In office buildings, lighting systems automatically adjust to complement the varying levels of natural light in different parts of a space to reduce the need for artificial illumination. Conditioned air is distributed through the floor rather than from the ceiling (as in most buildings), which means that since it travels a shorter distance it can be cooled less—and pressurized less—saving energy and increasing comfort. In residential buildings, openable windows permit natural ventilation to take advantage of wind currents and convection to cool spaces. Rainwater is collected and used for cooling systems, and for landscape irrigation. Roofs are light-colored to reflect heat. Building materials are chosen not only to fulfill their immediate function, but also on the basis of energy consumed in production, transportation distances, ease of maintenance, and potential for eventual reuse.
These technological fixes are undoubtedly useful, but they conceal a basic truth. Rather than trying to change behavior to reduce carbon emissions, politicians and entrepreneurs have sold greening to the public as a kind of accessorizing. “Keep doing what you’re doing,” is the message, just add a solar panel, a wind turbine, a bamboo floor, whatever. But a solar-heated house in the suburbs is still a house in the suburbs, and if you have to drive to it—even in a Prius—it’s hardly green. “The average New Yorker,” writes David Owen in Green Metropolis, “annually generates 7.1 metric tons of greenhouse gases, a lower rate than that of residents of any other American city, and less than 30 percent of the national average, which is 24.5 metric tons; Manhattanites generate even less.”5 He argues that what really makes a city green are not grassy roofs and rainwater cisterns, but density. In a suburban office campus, for example, people work in low, sprawling buildings and drive between them; in a city, people work in compact multistory buildings, use elevators (which are inherently energy efficient since they are counterweighted), and walk to lunch. Owen suggests that rather than conceiving of Utopian solutions, or complicated technological add-ons, planners should study existing cities that already offer “instructive examples of how to achieve low-impact urban living,” citing Manhattan and Hong Kong.6
Although extremely dense vertical cities conserve more energy and resources, they are not really models; simply put, the demand for Manhattan-type living is limited. But if Americans are to significantly reduce their carbon footprints, they will have to consider densification. Per capita carbon dioxide emissions in American cities are estimated to be twice as high as in Europe, and the so-called ecological footprints of American cities—the land area beyond the city proper that is required for food production, energy and resources supply, and waste assimilation—are correspondingly large.7 “The low-density auto-dependent American landscape makes sustainable living—such as walking, bicycling, or public transport—difficult,” writes Timothy Beatley, an urban-planning professor at the University of Virginia and the author of Green Urbanism. “American cities consequently have high carbon dioxide emissions, produce large amounts of waste, and draw in large amounts of energy and resources.”8
It will be difficult for Americans to emulate European cities, with their dense historic centers, different housing patterns, lower reliance on automobiles, and highly regulated urban development. Is there another model? The new Israeli city of Modi’in provides some useful lessons for achieving a denser and greener—in both senses—urbanism. Located halfway between Jerusalem and Tel Aviv, Modi’in has been built from scratch on open land that was previously a military reservation. Planning started in 1989, the first residents moved in 1993, and today the population has reached eighty thousand. The planning team is led by Moshe Safdie, who gained renown as the designer of Habitat 67, an innovative housing complex that was an example of what he called a three-dimensional community. Of Habitat he wrote, “I wanted to demonstrate that a city could be built at a population density comparable with the downtown areas of Montreal or Boston without compromising the quality of environment of each particular urban activity, whether it was shopping, or housing, or work.”9 Habitat, an attempt to raise housing density through a radically different design, was basically a megastructure solution. Modi’in is different: a city informed by post–Jane Jacobs urban design. I asked Safdie how Jacobs had influenced his thinking. “No doubt Jacobs’s book had a great impact,” he answered. “At the time we were all struggling with Miesian planning and the urban-renewal syndrome, and it’s interesting how the responses to Jane Jacobs differed. On one hand, the New Urbanism setting the clock back; in my case, actually feeling we needed to deal with her observations and values looking forward to a denser, more urban environment.” Modi’in includes a mix of housing types: apartments in tall buildings (located on hilltops to serve as landmarks); closely spaced single-family row houses; and the majority (two-thirds) consisting of walk-up flats in small three- and four-story buildings, six to eight units per building.
Safdie describes Modi’in as a conscious attempt to create a “normal” as opposed to a “planned” city. “The difference concerns a clearer articulation between the public domain and individual buildings,” he says. “In normal cities, buildings are organized along public streets. There is a variety of building types resulting from construction over time by many architects and developers, thus enhancing the identity of individual buildings. Planned cities with large-scale projects, in contrast, are large compounds within which many buildings are clustered without a street address. At Modi’in we were determined to achieve a finer-grain organization and parcelization of land, with a greater variety in the design of individual buildings.” To achieve this variety, Safdie’s team adopted a novel method of planning that combined overall guiding principles with piecemeal development. A master plan established the main thoroughfares, the general outlines of the neighborhoods, and the location of the town center. However, the detailed urban design of individual neighborhoods was delegated to several independent teams of architects and planners who were required to follow urban-design guidelines. (Safdie’s office planned one of the residential neighborhoods, as well as the town center.) The decentralization continued at the level of buildings, since within the neighborhoods, housing sites were allocated to different private developers (as in Battery Park City). Since the developers worked with a variety of architects, and since the neighborhood planners interpreted Safdie’s urban guidelines with varying degrees of strictness, the result is much more heterogeneous than most planned communities, more like a normal city.
The new city of Modi’in is a model for urban densification.
What sets Modi’in apart from strictly market-based planned communities is the emphasis on public uses. The residential neighborhoods, for example, are located on the hilly slopes, but the valley floors are reserved for parks, parkways, and sites for kindergartens, schools, clinics, and small shopping centers. The city is planned to be drivable, but much of the housing is within walking distance of the valley facilities, which are reached by means of landscaped walks that descend the hillsides and recall the pedestrian stairs of San Francisco and Montmartre. The low and dense town center, consisting of five- and six-story buildings, includes a mixture of offices, civic uses, and apartment buildings. An indoor shopping mall resembles a bazaar and contains a community theater as well as an adjacent outdoor market. Perhaps the most remarkable feature of the town center is the absence of surface parking lots and parking garages—all the parking is underground.
Modern housing along a traditional street.
Although Modi’in is not specifically designed to be green, it contains many resource- and energy-saving strategies. Density facilitates walkability as well as a local bus system. While the inhabitants, like most Israelis, own cars, there is a train to Tel Aviv (a twenty-minute ride), and a second line is under construction to Jerusalem. The forested areas of the hilly and otherwise barren site are kept in their natural states, and a wide greenbelt surrounds the city. Adding in nature preserves, protected archaeological sites, and open sports and recreation zones leaves almost a third of the eight-thousand-acre site unbuilt. The landscaping of parks is designed to minimize irrigation, with drought-resistant plantings and few lawns. Storm water is retained on the site and used for irrigation or infiltrated into an aquifer. Following national standards, all household sewage and gray water is piped to a regional recycling and purification plant, from whence treated water is distributed to agricultural areas. Through such measures, Israel recycles as much as 75 percent of its water, a remarkable figure. It has been estimated that 90 percent of homes in Israel use a solar water heater, which is required by law, and every dwelling in Modi’in has a solar heater on the roof.
The town center, which is a cross between a shopping mall and a bazaar, includes an outdoor market and a community theater.
Walking around Modi’in, I can’t shake the feeling of being in an early-twentieth-century Garden City, albeit hilly and with palm trees. This feeling is heightened by the appearance of the housing, which is mostly in the practical, modern style that is common throughout Israel, although one neighborhood, with tiled roofs and bright colors, reminds me of Southern California. Overall, the simple, white buildings recall the International Style common in older parts of Tel Aviv. The planners of Modi’in long debated whether it should be a “white city” like Tel Aviv (where buildings are plastered and painted white), or a “stone city” like Jerusalem (where so-called Jerusalem limestone is required on the exteriors of buildings). They decided on a combination of the two: stone in the town center and the valley buildings, but elsewhere, either plaster or stone.
When talking about the design of Modi’in, Safdie frequently refers to Patrick Geddes’s original plan for Tel Aviv. In the 1920s, during the British Mandate in Palestine, Geddes, who had earlier laid out neighborhoods in Jerusalem, was commissioned to create a master plan for the new city of Tel Aviv, which had been founded by Jewish settlers in 1906. He laid out the core of the city according to Garden City principles, with parks, boulevards, and landscaped pedestrian walkways. The result is both urban and gardenlike. During the 1930s, émigré German architects such as Richard Kauffman and the great Erich Mendelsohn built Gartenstädte neighborhoods in Tel Aviv and Jerusalem. Despite Jane Jacobs’s criticism of the Garden City in The Death and Life of Great American Cities, these neighborhoods have flourished and are much prized and admired today as humane and attractive living environments.
Tel Aviv incorporated two vital principles of Geddes’s vision. The first, as Mumford, who considered Geddes “my master,” explained, was to plan cities at a human scale to avoid the sprawling modern megalopolis, which Mumford called “the last word in imageless urban amorphousness.”10 The second was to avoid high densities, since “housing designed at three hundred to four hundred people to the acre—to say nothing of the greater number some favor—is not conducive to health, neighborly cooperation, or adequate child care,” Mumford argued.11 In Modi’in, which has a population density of about fifty people per acre and is intended to grow to a quarter of a million people, Safdie and his team have shown that Geddes’s and Mumford’s ideas still have relevance.*
Modi’in demonstrates that green urbanism does not require newfangled technological devices, but something more old-fashioned: good planning. Adapting these lessons to American conditions will require ingenuity. While densities of fifty people per acre are not uncommon in Israel, where most people live in apartments and flats, the majority of Americans live in single-family houses, at densities of ten to fifteen people per acre. Yet efforts will have to be made to achieve a denser way of life, while at the same time taking into account people’s desire for dispersed living in smaller cities. Broadacre will have to become Narrowacre. Densification does not necessarily mean high-rise apartments; it can be achieved through a combination of infill developments in cities and towns, and smaller lots and more compact (and probably somewhat smaller) houses in the suburbs. It will also require a greater variety of housing choices, not only freestanding houses on large lots, but twins and row houses, housing terraces, walk-up apartments, clusters of cottages, bungalow courts, and compact mews—all time-tested models that are worth revisiting.
Low-density communities can afford to ignore the public realm, but increasing the density of housing will require paying more attention to public amenities such as well-designed streets, public spaces, and town centers. The creative use of open green space in Modi’in, like the combination of development and parkland in Brooklyn Bridge Park, shows how active landscapes can complement dense living. Not Le Corbusier’s model of buildings-in-a-park but buildings and parks. A Garden City approach might be a useful compromise between dense urbanism and spread-out suburbanism. Forest Hills Gardens, for example, is a hundred years old but still has lessons to teach. With its mixture of low-rise apartments and different types of single-family houses, it reaches a gross density of about thirty-five people per acre—a good starting point. A more radical, and more urban, solution is the Yards in Washington, D.C. With its combination of old and new structures, residential and commercial uses, and social and market housing, it shows that it is possible to achieve high density without tall buildings.
The Yards is being completed, but many new urban developments remain on the drawing boards since the present recession has produced a virtual halt in construction and urban development. The last time this happened for an extended period was during the Great Depression of the 1930s, a building interruption that extended through the end of the Second World War. The effect on architecture and city building was devastating, and not just because little was built. The disruption was not only physical but intellectual: offices closed, careers were cut short, practitioners took early retirement, and the continuity of practice was interrupted. Much professional knowledge, normally transmitted between generations through apprenticeship, was lost. The urban accomplishments of the early 1900s, such as Forest Hills Gardens, depended on teamwork—among developers, planners, architects, landscape architects, builders, and public administrators—and the lack of new projects allowed these networks to unravel. Thus, by the 1950s, when the economy revived and cities began to think of rebuilding and replanning, few seasoned professionals were available. At the same time, a widely held view among the public was that the times called for change. This explains the willingness to attempt radical and untested urban interventions such as urban renewal, traffic separation, high-rise social housing in the cities, and dispersed planned communities in the suburbs.
The current stalled economy has produced a call for massive government spending in the public sector. Inevitably, much of this spending will take place in cities and metropolitan areas. Architects and planners will once again be tempted to implement grand urban visions—twenty-first-century versions of urban renewal and the Radiant City. The temptation will be particularly great since government-funded projects provide freedom from the constraints imposed by the market, an opportunity to replace demand-side urbanism with supply-side planning; us telling them what they should like, just as in the good old days. This temptation must be resisted. The urban lessons of the last hundred years should not go unheeded. Small is not always beautiful, but piecemeal urbanism has a long and proven track record. Effective planning should recognize that while the market is not always right, an aggregation of individual decisions is generally closer to the mark than the plans of willful urban visionaries, however exciting those plans appear on paper. Nor is striving to replicate the Bilbao Effect the solution to urban revitalization. History does not always have all the answers—new problems do sometimes require new solutions—but it behooves us to keep one eye on the past as we venture into the future. This is not about nostalgia or summoning an imagined past, but freedom from history is no freedom at all. The next city will include much that is new, but to succeed it cannot ignore what came before. Linking the past with the present, and seeing the old anew, has always been part of our improvised urban condition.
*Curiously, fifty people per acre is about the same as Raymond Unwin’s “twelve houses to the acre,” given the larger household sizes of his time. It is also similar to the density of midrise cities such as today’s Copenhagen and Stockholm.
