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Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
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Hybrid Cities

A Basis for Hope

GEETA PRADHAN AND RAJESH K. PRADHAN

Some years ago a problem shared by many cities manifested itself in such a dramatic way that even the skeptics among skeptics sat up with alarm. The people of Mexico City realized with a horror that their city was sinking. Water drawn over the years to sustain city life had far exceeded the amount that trickled down to replenish underground sources, triggering dramatic subsidence at times. Excessive paving had made matters worse, causing water run-off, flooding, aquifer depletion, and reliance on an expensive water supply system. Mexico City illustrates starkly how unsustainable our current urban practices are.

In this paper we offer an alternative approach to the development of cities inspired by the Italian writer-philosopher Italo Calvino. In Invisible Cities (1986), Calvino describes the empire of the Tartar emperor Kublai Khan, which is crumbling. Khan is devastated. To divert him, the Venetian traveler Marco Polo recounts stories about the cities he has seen during his travels. He describes cities of memories, cities of dreams, thin cities and wide cities, trading cities, cities of desire, signs, and eyes, cities of names, and hidden cities. Soon it becomes clear to Khan that each of these fantastic places is really the same place—Kublai Khan’s empire. But the down-in-the-dumps Khan sees no hope of getting out of the ever closing-in inferno. Polo tells him:

There are two ways to escape suffering it. The first is easy for many: accept the inferno and become such a part of it that you can no longer see it. The second is risky and demands constant vigilance and apprehension: seek and learn to recognize who and what, in the midst of the inferno, are not inferno, then make them endure, give them space.

Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×

We give space in the following pages to an idea anchored in the wisdom of the past and the vast literature on administrative decentralization. We take into account some scientific and technological advances, tempering the grandeur and visions of utopia with the realization that the world’s finite resources cannot keep pace with human activity and population growth. Like the spaces Calvino allows within the inferno, we try to give legitimacy and room for the development of small trends and innovative concepts in response to the problems of urbanization. In the end, we hope to offer a new model of development, a hybrid approach that combines the best of rural and urban attributes to create “a village in a city, a city in a village.” Metaphorically, this model will encourage us to look beyond cities and rethink our urban centers as we design the cities of tomorrow. It will suggest subduing the inferno and diffusing pressures within megacities by bringing, as it were, the countryside in.

The world population, which reached 6.1 billion in mid-2000, is expected to increase to 8.1 billion by 2030 (United Nations, 2001). Projections show that almost all of this growth will be concentrated in urban areas of the less developed world. Rural-to-urban migration and the transformation of rural settlements into cities are expected to be key contributors to this trend. Although an increasing share of the world population lives in urban areas, the percentage of people living in very large urban agglomerations—called megacities—is still small. In 2000, 4.3 percent lived in cities of 10 million or more; by 2015, the number is expected to rise to 5.2 percent. Cities of 5 to 10 million inhabitants, which currently account for 2.6 percent of world population, will hold about 3.5 percent by 2015. By comparison, the number of people living in smaller cities, although increasing at a slower pace, is considerably larger. In 2000, 28.5 percent of the world population was living in cities of one million or less; by 2015, cities of this size will account for 30.6 percent of total population.

Cities, which account for just 2 percent of the world’s surface, use a disproportionate amount of the world’s resources. For instance, they produce roughly 78 percent of carbon emissions from the burning of fossil fuels and the manufacture of cement; 76 percent of industrial wood is used in urban areas. Some 60 percent of the planet’s water tapped for human use goes to cities in one form or another (O’Meara, 1999).

Cities account for a majority of the world’s wealth and provide more than 50 percent of the world’s employment. If population growth remains on its current trajectory, the global workforce will swell from about 3 billion today to nearly 4.5 billion by 2050 (World Resources Institute, 2000). In a desperate search for jobs, higher income, and more options, people will continue to be drawn to cities.

However, many urban environments are inhospitable and create incentives for people to move away and escape city life. Congestion, health risks related to pollution, ungovernability, and social chaos are common problems in some of the world’s largest cities. According to the World Resources Institute (1996), at least 220 million people in cities of the developing world lack clean drinking water;

Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×

420 million do not have access to the simplest sanitation; and between one-third and one-half of city trash is not collected, contributing to flooding and the spread of disease. Domestic and industrial effluents released with little or no treatment into waterways affect the quality of water far beyond cities, rendering many urban rivers, for example, the Pasig River in Manila and the Yamuna River in New Delhi, biologically dead. Breakdowns and undercapacity in the aging infrastructure of cities, especially water supply and sewer systems, increase the incidence of waterborne and water-related diseases. At any given time, close to half the urban population suffers from one or more of these diseases (World Bank, 2000).

Rising rates of automobile ownership and the absence of public transportation and environmentally sound rapid transit systems have led to unprecedented levels of pollution and traffic congestion in cities. Urban air pollution is estimated to be responsible for more than three million deaths annually worldwide, almost all of them children (World Health Organization, 1997). The air in some cities in Latin America, China, and India has concentrations of pollutants, such as nitrogen oxide, sulphur dioxide and particulates, that are two to four times the safe levels set by the World Health Organization (Davis, 1999). The amount of air pollution children in these cities are exposed to is equivalent to their smoking two packs of cigarettes per day (World Bank, 2000).

Vehicle exhaust, the dominant ingredient in urban air pollution, is also spewing lead into the air. This toxic metal impairs the kidneys, liver, and reproductive system, and at high levels causes irreversible brain damage. A 1990 study of atmospheric lead pollution in Bangkok estimated that 30,000 to 70,000 children risked losing four or more points on their IQ levels because of high lead concentrations, and many more risked smaller decreases in intelligence (World Bank, 2000). Recent studies suggest that about two-thirds of children in New Delhi and an even greater proportion of children in Shanghai have blood levels of lead higher than the levels estimated to cause adverse health effects. In Cairo in early 1999, traffic in the city’s industrial areas contributed to atmospheric lead concentrations that exceeded health guidelines by a factor of 11 (O’Meara, 1999).

Despite the problems associated with the growth of cities, development policies have continued to favor the urban sector. This “urban bias,” to borrow a phrase popularized by the economist Michael Lipton in Why People Stay Poor (1977), is derived from a much earlier debate on how less industrialized nations should modernize. The strategy that gained acceptance, generally credited to Arthur Lewis (1954), was to focus on cities (as opposed to agricultural areas) as places that could provide jobs, produce goods at low wages due to surplus labor, generate wealth through exports and exchange, and create a dense environment that would encourage economic interdependence and innovation. The result of this development strategy, however, was excessive migration to cities, urban sprawl, and the relative stagnation of villages. Many cities, especially in the less industrialized world, have become unmanageable, ungovernable, and unsustainable.

Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×

In the United States and the rest of the industrialized world, the debate about cities is now framed differently. The focus is no longer on economic growth per se but on ways to improve the quality of urban life. These are new expressions of old ideas. Historically, American city planners saw the ideal city as one that took care of three aspects of human experience—work, family, and leisure. Over time, however, the ideal work life, family life, and leisure time have come to be associated with suburbs rather than inner cities. As family concerns about schools and safety in cities increase, employment and leisure activities have increased in the suburbs. The results of this out-migration, or suburban sprawl, have been a substantial loss of agricultural land and forests, urban disinvestment, an increase in transportation requirements, and an increase in suburban residential and commercial land use.

The change in America’s population illustrates this trend. The urban population, including people living in suburbs, grew from 60 percent of the total population in 1950 to about 80 percent in 2000 (Ecological Cities Project, 2001). In the Boston metropolitan region, for example, more than 37 percent of open space was lost to urban sprawl in just 50 years (Pradhan and Kahn, 2000). The impact of increased automobile use has also led to a decrease in productivity. Drivers in 70 metropolitan areas spend an average 40 hours a year sitting in stalled traffic, resulting in wasted fuel and lost productivity that costs about $74 billion annually (O’Meara, 1999).

Concerns about health, productivity, and overall quality of life provide incentives for people to move away from cities. People with the means may choose to maintain two homes, one in the countryside where they can enjoy serenity, the other in the bustling city where they can enjoy diversity and cultural activities, work, and create wealth. This phenomenon of dual habitation, which is growing in the West and among affluent city dwellers in the developing world, is an indication of what many more people would do if they could.

As cities continue to expand, the pressures to manage water and energy resources, organize food production and distribution, and manage basic amenities, such as housing, transportation, and public health, will increase. Particularly in megacities, access to and control over these resources and services are increasingly becoming arenas of social conflict, raising demands for social justice and civic representation. Ironically, even if populations do not grow at the predicted rate, cities will still have to contend with the normal wear and tear on vital infrastructure and more discriminating, politicized inhabitants.

Considering the enormity of the problems facing cities, our responses have been timid. They have ranged from popularizing environmentally sound technical solutions (e.g., energy conservation equipment and pollution-prevention and cleanup technologies) to appealing to people to establish a deep (spiritual) bond with the environment and nature. However, projected growth in urban population and demand for services cannot be sustained by tinkering with technology or conventional city planning tools. And the awareness-raising strategy appears to

Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×

disregard the basic human impulse to act on the basis of narrow self-interest. In other words, neither approach provides much hope for significantly improving the quality of life in today’s sprawling cities and emerging urban centers.

What we need is an inspiring vision that provides a new direction for cities of the future. We need a utopia of sorts, a basis for hope, and a redefinition of what a city is. One such vision is the “hybrid city,” the concentrated development of urban centers with populations of one million or less and the creation of countryside or small-town-like environments within large urban centers.

A FRAMEWORK FOR HYBRID CITIES

The hybrid city would be a sustainable community that emphasizes civic engagement, social justice, environmental soundness, and economic diversity. It is based on an understanding of factors that have lured people over the ages to cities and of the qualities of life people seek when they move to the countryside and small towns. We have attempted to provide a broad framework—rather than “quick fixes” and ad hoc solutions—for creating what we call “a village in a city, a city in a village.” The hybrid city attempts to combine the best qualities of cities—diversity, density, innovation, economic mobility, and access to means for human development—with the best qualities of villages or small towns—cultural wisdom, frugality, conservation, resource efficiency, a sense of scale and place, self-reliance, and a sense of community and connectedness.

The vision is based on lessons learned from innovations in food production, the creation of open space, waste management, and transportation, which were adopted to take the heat off the “infernos” that many large cities have become. These trends and innovations also offer hope for the sustainability of smaller urban centers. A few examples should suffice.

Village-like Self-reliant Activities in Cities

Many small-scale efforts to enhance urban sustainability or livability have successfully provided residents with goods and services produced locally. They are guided by the principle of self-reliance, a characteristic typically associated with the village or country town of the past, when transportation options were limited. Chinese cities, for instance, have long reserved surrounding areas for agriculture and used city-generated wastes to fertilize the fields, which, in turn, have met a significant portion of city demand for vegetables, meat, and poultry. In Africa, urban agriculture is a survival strategy for the poor (O’Meara, 1999). In Boston, 150 community gardens augment the food budgets of families in the inner city; the gardeners are often low-income families and the elderly. Urban gardeners in New York City are organizing to protect their ad-hoc urban gardens. The popularity of public markets that stock locally grown produce and food products is testimony to the latent demand for urban agriculture.

Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×

Hybrid cities would make urban agriculture an explicit element of city planning. To the extent that this would create a variety of jobs in production, processing, and support industries (favoring less-skilled workers), the strategy would also further the goals of equity and social justice. From an architectural or urban design point of view, urban agriculture would enhance diversity in cities.

Village-like Open Spaces and Clean Air

Perhaps inadvertently, urban agriculture also provides badly needed open space in congested cities. Some U.S. metropolitan centers, such as Portland, Oregon, are working explicitly on ways to limit their boundaries, limit growth, and increase countryside-like open spaces. By moving a major highway underground, for instance, Boston is creating huge open spaces in the heart of its downtown. To reduce air pollution and create a more pristine environment, Chattanooga has replaced automobile traffic in the downtown area with free public transportation that runs on nonpolluting fuels (World Resources Institute, 2001). The change has led to massive economic investments in the city center.

Village-like Frugality and Resource Conservation

Curitiba, Brazil, has linked its waste recycling program to its efforts to boost nutrition. For every bag of recyclables citizens turn in, they receive a bag of locally grown vegetables. Similar recycling strategies are being used on an industrial scale. For instance, in Kalundborg, Denmark, waste from one industry feeds directly into another as raw material in a kind of “industrial symbiosis.” Metropolitan Tokyo, with more than 80 percent of its land covered by asphalt, is harvesting rainwater for nondrinking uses by placing tanks on rooftops (O’Meara, 1999). Boston is conserving its drinking-water resources by replacing leaky pipes, installing water-saving features, and educating the public about the importance of water conservation. The city has reduced water loss in the past two decades from 33 percent to about 11 percent (Pradhan and Kahn, 2000).

City in a Village

With technological advancements, combined with traditional wisdom, we can create an island of city life surrounded by a sea of countryside. Anna Hazare’s Raley Gaon Siddhi village project in Maharashtra, India, is one example (Hazare, 1997). The project has been hailed as one of the most successful sustainable community projects in India and has been replicated in more than 600 villages. The idea behind the Raley Gaon Siddhi project is not to create an urban center but to create a sustainable village with town-like diversity that provides a range of jobs and uses low-cost, environmentally sound technologies and watershed management to sustain village life.

Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×

Behind many of these innovative approaches to urban sustainability is the unspoken idea of providing cities with the qualities associated with life in the countryside. With technological advancements, city planners can create environments that respond simultaneously to the longing for the intensity of city life and the ideal of small-town life in a global economy. The “city in a village” can focus attention on the development of rural areas and small towns, “potential cities,” as a way addressing the problem of unsustainable concentrations of population and economic activities in large cities.

HYBRID CITIES, DIVERSITY, AND VOICE

Another way of looking at hybrid cities is to focus on the issue of diversity, one of the defining characteristics of cities. The kinds of innovations we have just described will lead to a broadening and deepening of diversity. The coexistence of different ideas, opportunities, and experiences would create the conditions for constant innovation and creativity. The hybrid city would be both an actor in the global economy and a self-reliant entity that meets the needs of the local population for basic goods and services. Its diverse economy would be both industrial and craft-based, high tech and low tech, formal and informal.

Ideally, a hybrid city would be relatively small, governable, and manageable. It would provide a sense of community and allow people to feel connected to each other and to their city, thus building social capital and encouraging civic involvement. The hybridization of an existing megacity could occur in a number of ways, some of them complementary. First, a megacity could be broken up administratively into several small towns. Second, planning could be much more community-based or neighborhood-based, consistent with the decentralized units. Third, countryside-like spaces and activities could be incorporated along the periphery of a city, as well as in the city itself. Similarly, one can imagine high-technology-based urban clusters in the countryside. The idea, in other words, is to diversify both the city and the countryside.

To put it differently, the small town (or the countryside) should be a planning tool for the development of existing large cities. Because a hybrid city would incorporate ideas, such as direct political representation, inherent in small towns and rural settings, it would encourage civic engagement and social justice, which are critical to making cities more sustainable but are often lost in the rush to make cities more modern or more manageable. By advocating village-like or craft-like activities in production, processing, manufacturing, and services, the hybrid city would attempt to create a variety of employment opportunities and outlets for many skills, such as crafts and manufacturing, that are becoming irrelevant in the urban economy.

Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×

A CONGLOMERATION OF SMALL TOWNS

By conceptualizing the big city as a conglomeration of small towns interspersed by pockets of countryside, resource allocation and city planning would necessarily become neighborhood-based or community-based activities. It would facilitate civic engagement by relying on small administrative units as opposed to the centralized administration of traditional megacities. Thus hybrids would decentralize power and legitimize many different voices. Finally, by drawing attention to small urban centers and developing urban clusters within villages—possibly the hybrid cities of the future—investments would be directed to relatively forgotten communities.

The idea of enjoying the best of both worlds is not new. When conditions in cities became unbearable after the Industrial Revolution, urban thinkers developed utopian vision combining the best technologies with ideas of social justice to create equitable societies in harmony with nature. Whether or not we agree with them, ideas from Ebenezer Howard’s garden cities movement, Le Corbusier’s skyscrapers set in open parkland, and Frank Lloyd Wright’s suburban sprawl made possible by the automobile, found their way into twentieth century urban planning throughout the world. Such is the power and influence of visions!

Unlike some of the utopian visions of the past, the hybrid city approach does not pretend to be a fully developed idea. It aims simply to unify disparate and badly needed attempts to ensure sustainability by mixing, like an alchemist, seemingly opposite elements—the city and the countryside, the megacity and the small town.

REFERENCES

Calvino, I. 1986. Invisible Cities. Translated by W. Weaver. Orlando: Harcourt Brace.


Davis, D. 1999. Urban Air Pollution Risks to Children: A Global Environmental Health Indicator. Washington, D.C.: World Resources Institute.


Ecological Cities Project. 2001. Changes in U.S. Metropolitan Populations and Land Area (1950–2050). Available online at <www.umass.edu/ecologicalcities/landusechange2.html> (March 27, 2001).


Hazare, A. 1997. A Veritable Transformation, Anna Hazare. Translated by B.S. Pendse. Raley Gaon Siddhi, Maharashtra, India: Raley Gaon Siddhi Pariwar Publications.


Lewis, W.A. 1954. Economic Development with Unlimited Supplies of Labour. Manchester School of Economic and Social Studies 22(2): 139–191.

Lipton, M. 1977. Why People Stay Poor: Urban Bias in World Development. Cambridge, Mass.: Harvard University Press.


O’Meara, M. 1999. Reinventing Cities for People and the Planet. Worldwatch Paper 147. Washington, D.C.: Worldwatch Institute.


Pradhan, G., and C. Kahn. 2000. The Wisdom of Our Choices: Boston’s Indicators of Progress, Change, and Sustainability. Boston: The Boston Foundation.


United Nations. 2001. World Population Prospects: The 2000 Revision. New York: United Nations.


World Bank. 2000. Entering the 21st Century. World Development Report 1999/2000. Washington, D.C.: World Bank Publications.

Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×

World Health Organization. 1997. Conquering Suffering, Enriching Humanity. World Health Report. Washington, D.C.: World Health Organization.

World Resources Institute. 1996. World Resources 1996–1997 Guide to the Global Environment: The Urban Environment. Washington, D.C.: World Resources.

World Resources Institute. 2000. Global Trends. Washington, D.C.: World Resources Institute. Available online at <www.igc.org/wri/powerpoints/trends/sld001.html> (March 27, 2001).

World Resources Institute. 2001. Air Pollution: Chattanooga, Tennessee. Available online at <www.wri.org/enved/suscom-chattanooga.html> (April 18, 2001).

Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×

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Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×
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Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×
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Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×
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Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×
Page 98
Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×
Page 99
Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×
Page 100
Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×
Page 101
Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×
Page 102
Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×
Page 103
Suggested Citation:"Hybrid Cities: A Basis for Hope." National Academy of Engineering. 2002. Engineering and Environmental Challenges: Technical Symposium on Earth Systems Engineering. Washington, DC: The National Academies Press. doi: 10.17226/10386.
×
Page 104
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Dealing with the challenges presented by climate change or rapid urban development require cooperation and expertise from engineering, social and natural sciences. Earth systems engineering is an emerging area of multidisclinary study that takes a holistic view of natural and human system interactions to better understand complex systems. It seeks to develop methods and tools that enable technically sound and ethically wise decisions. Engineering and Environmental Challenges presents the proceedings of a National Academy of Engineering public symposium on Earth systems engineering.

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