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CityReads│Is the compact city more sustainable?
Michael Neuman,2005. The compact city fallacy.Journal of planning education and research, 25(1), 11-26. Souce: http://jpe.sagepub.com/content/25/1/11.short Cover picture source: http://img1.imgtn.bdimg.com/it/u=1601825058,1738837819&fm=21&gp=0.jpg
Massive migration to metropolitan areas and decentralization within metropolises are concurring. Concentrating people and activities in urban areas confers advantages, yet given the choice and resources to exercise it, many locate in the sprawling metropolitan periphery. It’s obvious that there is a paradox between urban desirability and suburban livability. Despite many great efforts over the generations, this paradox has yet to be adequately resolved. Recent attempts to halt sprawl and improve urban livability have been made by compact city, smart growth, and healthy community. How effective are these options in attaining a deep-seated shift in community building toward truly sustainable communities? Are the compact cities more sustainable than the noncompact cities? This essay will examine factual evidence and intellectual foundations regarding sustainability to judge the question in a better position. This article is organized into six sections. The first three part is titled by ‘the compact city’, ‘urban sprawl ’ and ‘the compact city paradox ’. The planning profession and academy take as axiomatic that the compact city is more sustainable than sprawl. The evidence is equivocal and does not necessarily support that claim. The purpose of the final three sections is to raise the question whether urban form, compact or otherwise, is the best planning strategy. By examining the intellectual traditions and principles of sustainability, the author analyzed the compact city to evaluate the current practices in planning and building and to test whether practice follows the common principles. The conclusion posits that the main principle of sustainability, process, is more critical than form—compact or otherwise—in attaining a more sustainable city.
The term compact city conveys the opposite of urban sprawl. The compact city, we are told, is more energy efficient and less polluting because compact city dwellers can live closer to shops and work and can walk, bike, or take transit. Proponents claim it promotes more community-oriented social patterns. After all, the current American compact city movement—originated in social critiques of zoning and suburbia. In the United States, compact cities are also called transit-oriented developments and neotraditional towns and are promoted through the smart growth movement. Despite extensive literature on compact cities, surprisingly, a definition of one does not exist. Table 1 presents a first-cut list of characteristics of the compact city that can be used to guide future research. These criteria in the table do not in and of themselves make the compact city sustainable across a full range of parameters. Preliminary evidence testing the compact city vis-à-vis sustainability suggests that the relation between compactness and sustainability can be negatively correlated, weakly related, or correlated in limited ways. For example, social equity has a limited relation with compactness; While short trips to local activities may decrease, travel distances for those seeking specialized employment, unique shopping, or singular leisure pursuit can be independent of urban density. And growth in car ownership and weekend air travel have led to the inability of physical design alone to reduce travel demands of energy-rich transport modes; In Netherlands where with compact cities and high levels of nonautomobile travel, average personal energy use for transportation in different spatial settings ranged only 5 percent(see Table 2). In a careful and revealing review of empirical studies on the effect of urban form on transportation, Peter Hall (2001) found that the research results are equivocal, for many of these studies have examined one parameter of travel (distance, time, frequency) instead of more complete assessments. For example, a study based on British National Travel Surveys concluded that highest trip frequency is in areas where population density is low, while another study found no significant statistical link between trip frequency and population density. A study found a weak link between densities and transportation energy use, while another believe “Travel is much more strongly linked to fuel prices and income” than population density. This research project casts doubt on the orthodoxy that increasing building densities will necessarily reduce travel in towns and cities. While energy used by the transport sector is significant, other sectors are more important. In the United States in the year 2000, the transport sector used 27 percent of all energy, a 3 percent increase from 1950. Buildings consumed 38 percent, up from 29 percent in 1950. And total household energy use rose thirteenfold between 1950 and 1992, while population rose only 50 percent in this same period. Sustainability in urban settings also involves health and well-being. Simmel and Wirth suggested that high density causes emotional stress and other negative psychological conditions. And an empirical survey on the metroregion of Barcelona and found that lower densities and more open space in the urban fringe increased an individual’s perceived welfare. Some studies test how different urban forms are correlated with personal health. The hypothesis driving them is that compact form and mixed uses enable people to walk and bike more, thus being more fit. But those studies need to be more carefully designed because there are confounding factors---diet, genetics , and health care, etc. This brief report on empirical evidence suggests that the data are still inconclusive.
The problems associated with urban sprawl have long been recognized. Urban sprawl results from the confluence of several factors such as the lure of cheap open landoutside the city, advances in transportation and the rise of the real estate developer. As an outcome of the population growth and geographic expansion of cities, urban sprawl has given rise to many new terms such as satellite town, edge city, exurb and megacity. All of these phenomena are called urban sprawl, this is because suburbs and exurbs are rapidly urbanizing into cities and under cities’ jurisdiction. Sprawl has both positive and negative effects. Burchell’s study showed the greatest savings gained from growth controls were in land consumed and infrastructure built. And following is the characteristics of American urban sprawl defined by Burchell.
The paradox of the compact city refers to the inverse relation of the sustainability of cities and their livability. For a city to be sustainable, the argument goes, functions and population must be concentrated at higher densities. Yet for a city to be livable, functions and population must be dispersed at lower densities. Many observers claim that a compact city is more sustainable and it is supported by many polices. Yet the policy desire for compact urban form belies two facts. One is that people who have the means to do so have long been voting with their feet and moving from the central city to the outskirts. The second fact is the intensity and proximity of certain uses have made cities, or parts of them, toxic flashpoints detrimental to human and ecosystem health. Now two contradictory tendencies—compact urban form and sprawling urban form both continue. Dispersal and segregation of population and activities continue as inhabitants and business owners seek a higher quality of life, while relocation to and reinvestment in the central city, especially its core, continues as well. One might relegate this to a simple matter of personal preference. But many cities such as Philadelphia, Baltimore have square miles of compact residential neighborhoods, once livable and vital, that have been vacant for years though their metro areas have grown in population and surface area. This fundamental and deeply seated paradox has not been solved yet. The author think one way to examine this paradox is to see if the compact city is sustainable.
There are four common themes for sustainability: process, health, place-specific conditions and interrelationships among system components. Does the compact city respond to these four common themes? Is the compact city the result of a long-term, evolutionary process? Compact city is not the result of a long-term, evolutionary process. The town does not grow bit by bit over time, accumulating uses, meaning, size, and so on. It is all built nearly all at once. Is the compact city a healthy city? The health of a city is determined by many factors. Only some factors are affected by density. The origins of modern urban planning is derived from devastating criticisms of city crowding in the nineteenth century. Industrial cities became less healthy as they became denser. Today, the tables have been turned. Sprawling metropolises are unhealthy; while that sprawl’s opposite, compact, should be more healthy. Study found gasoline consumption is lower in European cities compared to American and Australian counterparts. Yet gasoline is significantly cheaper in the United States. In addition, compact settlements with an emphasis on density, pedestrians, and public transportation only address a few of the ills attending modern metropolises. Is the compact city a place-specific solution? All good design is context specific, but many compact cities in fact are often insensitive to context whether social, environmental, economic, or political. Another problematic aspect of the compact city analyses is that they have placed a premium on a single operational measure: population density. This tendency to reduce a complex entity—the city—to one criterion—density—constrains research and biases action. Does the compact city deal with interrelationships? Partly. Segregation of uses still occurs in compact cities. Commercial and civic uses dominate the center, and housing remains on the periphery. Many people still must commute, often long distances. Economic and class segregation still occurs. Most new urbanist towns are enclaves of the middle and higher classes and are predominately populated by whites. Compact forms do impart advantages. These include lower land consumption, cheaper infrastructure and utility costs, and resource protection. Yet many compact developments are still mostly residential, still distant from a city or town. This necessitates daily travel for shopping, work, and entertainment. Thus, they contribute to sprawl. The data regarding the sustainability of compact cities are not conclusive. Because cities are not just physical forms and because even their material aspects are manifest in dimensions other than density and compactness, we have to look beyond the compact city for answers to the sustainability question. Moreover, the debate itself needs to be reframed, which I undertake in the following conclusion.
This essay explored representations and meanings of sustainability and compact cities. Compact city seems to be occasioned by the existence of sprawl. Yet by countering sprawl with compact cities, proponents remain on the same playing field with their counterparts. They have not raised the level of the game. Instead, they have reverted back to an old game. Form is both the structure that shapes process and the structure that emerges from a process. The question that should be asked is whether the processes of building cities and the processes of living, consuming, and producing in cities are sustainable instead of if compact city is more sustainable. The purpose of this article has been to identify the compact city fallacy. The compact city fallacy holds that the compact city is neither a necessary or sufficient condition for a city to be sustainable and that the attempt to make cities more sustainable only by using urban form strategies is counterproductive. Conceiving urban form as a processual outcome of urbanization opens the door to a new and dynamic conception of urban planning. Form is a snapshot of process and is not measurable in terms of sustainability. Asking whether a compact city, or any other form of the city, is sustainable is like asking whether the body is sustainable. The proper question is not if the body is sustainable, but rather, does the being that inhabits the body live sustainably? If the city is to survive, process must have the final word. In the end the urban truth is in the flow. There is no such thing as a sustainable city. Cities have always been dependent on their hinterlands and distant counterparts for food and trade. The attempt to attain sustainability via physical means alone is nonsensical. We should envision sustainability as a coevolutionary process, then the idea and ideal of a sustainable city is a viable one that we can strive to reach.