Planning Practice Feature

The Myth of Sustainable Cities

by Robert T. Ernst

Perhaps it is time for practicing planners to be honest with ourselves. Cities will never be environmentally sustainable, or eco-anything.

People who refer to cities as sustainable can best be understood as wistfully appealing to a fashionable myth or to a wished-for fiction rather than reality. What cities can and should be is less environmentally and energy profligate. In other words, they should be greener, smarter, more equitable, and better than the existing cities most of us practicing planners have had a hand in planning and building. To say we can make cities environmentally sustainable involves smoke and mirrors and is intellectually unsupportable.

Marking progress toward planning better cities should be our metric, not something as intellectually indefensible as environmental sustainability. We should forget we ever heard the term "sustainable cities" and focus on environmental values people of all political persuasions share and support. Throwing the term "sustainable cities" into the trash bin is well-advised.

 During the past several decades, planners have been exposed to the concepts of sustainability, smart growth, green cities, etc. from numerous sources, the great majority of which were created by urban and regional planners, and landscape architects (McHarg 1969; Godschalk and Parker 1975; Spirn 1984; Rees and Wackernagel 1996; Innes and Booher 2000; Berke 2002; Wheeler 2004; Beatley 2010). Another level of complexity was added when the concept of sustainability science was introduced early in the 21st century (Kates et al. 2001), and supporters began concentrating explicitly on the dynamic interactions between natural and social systems (Clark and Dickson 2003) and how those interactions affect the challenge of sustainability (Reitan 2005). In addition, many universities — including Stanford University, University of Oregon, and University of Kentucky, among others — have established centers and initiatives dedicated to sustainable. U.S. cities such as Seattle, Portland, Boston, Austin, and Jackson, Mississippi, also have adopted sustainable initiatives. As one final indication of the mainstream status of the sustainable cities concept, in 2000 the American Planning Association published its first Policy Guide on Planning for Sustainability.¹

Defining Sustainability

This commentary focuses on cities and sustainability; therefore, defining our terms is a good place to begin. Without getting overly pedantic, the term city refers to relatively large, permanent centers of human populations engaged in socioeconomically productive activities. Defining sustainability is more problematic since varying definitions abound. Perhaps the best-known definition of sustainable development is the one established by the United Nations World Commission on Environment and Development (1987), also widely known as the Brundtland Commission: "Sustainable development seeks to meet the needs and aspirations of the present without compromising the ability to meet those of the future." At the United Nations World Summit (2005, 2) it was noted that the 1987 WCED definition of sustainability required reconciliation of environmental, social, and economic demands, or what have become known as the "three pillars" of sustainability.

Since the Brundtland Commission's hallmark effort, sustainable development has been defined in a number of ways. Fowke and Prasad (1996) identified at least 80 different definitions, many of which were competing and a number that were contradictory. Parkin et al. (2003) reviewed more than 200 definitions of sustainability and sustainable development. And Hopwood, Mellor, and O'Brien classified and mapped numerous different approaches to sustainable development, which they viewed as a "challenging and contested concept" (2005, 38).

"Appropriated" Ecosystem

Regardless of how the term is defined, a critical consideration when the concept of sustainable cities is being discussed is environmental. City dwellers depend on productive ecosystems and habitats outside the city proper for food, energy, water, waste disposal, and renewable and non-renewable resources required to build dwellings, offices, and retail space and to manufacture the furnishings, equipment, materials, and supplies used in everyday life. That extended ecological footprint (Wackernagel 1994), also widely known as appropriated ecosystem, required by cities to function is seldom, if ever, considered by practicing planners in assessing the needs of cities or the effects of urban life on the larger environment (Jansson et al. 1999). The goods and services produced by ecosystems are said to be "appropriated" through trade and commerce with distant cities. For example, coffee that is produced in the highlands of Ethiopia or Colombia is consumed by customers in Starbucks and other coffee outlets and supermarkets across North America. When Folke et al. (1997) measured the appropriated ecosystems of cities around the Baltic Sea, they found those footprints to be at least 565 to 1,130 times larger than the areas of the cities themselves.

That concept of appropriated ecosystem has meaning in real-world terms as well as in academic journals. As an example, the Dallas-Fort Worth-Arlington Metropolitan Statistical Area consists of 9,286 square miles. If the mean (847) of the Folke et al. study is used to calculate that metro area's ecological footprint, the result is an area of about 7,865,240 square miles, or 29 times the area of the State of Texas and slightly more than twice that of the entire United States. If the lower end of the Folke range is used as a multiplier, the appropriated ecosystem for the Dallas metro area is about 5,246,600 square miles, or one and one-third times larger than the area of the United States. Even though appropriated ecosystems are well beyond the control of practicing planners, that distancing effect does not make them less critical to the future of cities and their urban inhabitants or to the viability of the sustainable city concept.

Exploring the many facets of urban sustainability requires an examination of the physical effects urban development has on natural environment systems. Readers can participate in that challenge by thinking about what the area that became Rome was like in 800 BCE, Manhattan Island in 1500, Los Angeles in 1600, or Chicago in 1700. No one would claim those areas were anything like they are today. Those involved in the process of creating cities destroyed or degraded the environment almost beyond recognition by building vertical and horizontal hardscapes unlike anything encountered in a natural setting (Campbell 1996, 297). Residences took the place of forests, meadows became shopping centers, free-flowing streams were transformed into concrete channels or underground drainage systems, central business districts grew over riverside terraces, wetlands were drained and converted into industrial areas, and native vegetation was removed and replaced with exotic species.

All the LEED-certified buildings and delightful, walkable, diverse, connected, human-scale streetscapes in the world will not disguise the fact that those cultural artifacts were built on the ruins of natural ecosystems that had been functioning in place for many thousands of years. Therefore, if cities are about destroying and degrading ecosystems, the question that must be asked is how then can they be characterized as environmentally sustainable? That question is especially pertinent today when virtually all of the world's population growth for the foreseeable future is projected to occur in urban areas (Cohen 2004, 48).

The Unsustainability of Agriculture

If we return to the concept of ecological footprint, all or almost all city inhabitants depend on food produced by agricultural enterprises at considerable distance from the city center. The most critical point about that situation is not the incurred transportation or carbon-related costs, but the very nature of agriculture. Cultivated fields are not natural phenomena; they are replacements of the previous natural ecosystems and destroyers of habitat and biological diversity (Daily 1997; Hall 2004). And, if destroying and degrading ecosystems is not sufficient evidence to indicate agriculture's non-sustainability, the dominant agrochemicals used today are responsible for the vast majority of the eco-toxicity found in freshwater sources (Tilman 1999) and for the well-documented dead zones found off the coast of Louisiana (Rabalais et al. 2010) and throughout the world.

But that view of agriculture is not universal. According to the American Society of Agronomy (1989, 15), sustainable agriculture is one that, over the long term, "enhances environmental quality." Although that statement in itself should be sufficient to raise eyebrows, critical observers may wonder how the quality of biological systems can be enhanced when the systems themselves have been ripped out and replaced by many hundred thousand square miles of corn, soybean, hay, wheat, and other crops. Therefore, a logical question would be exactly what part of agriculture at any scale can be interpreted as environmentally sustainable? As far as biologists can tell, apple orchards, cotton fields, and rice paddies, etc., are monocultures rather than essential features of natural ecosystems. Agriculture may become economically sustainable, but only at the expense of destroying indigenous ecological systems, habitats, communities, soils, and biodiversity. The conclusion is evident: Agriculture can never be regarded as environmentally sustainable.

What we have, therefore, is a situation consisting of cities that were created by destroying natural environments and urban residents who are supported by agriculture that was created by destroying natural environments and, yet, many planners blithely insist that system is or can become environmentally sustainable (Wheeler 2004). That existing situation with respect to cities is one of meaningless lip service being paid to the concept of environmental sustainability while economic sustainability is more often the true focus of attention. Thus, people who refer to cities as sustainable can best be understood as wistfully appealing to a fashionable myth or to a wished-for fiction rather than reality. To see the world as we want it to be, we are encouraged to close our eyes so we do not see the world for what it is. Lewis Carroll would have been hard pressed to create a more phantasmagorical view of reality.

Urban Water Supply

It is also important to explore, at least briefly, how urban water and energy supplies fit into the current conception of sustainable cities. Because many cities worldwide are located in arid or semi-arid environments, here's a small but telling query that concerns the sources of potable water for Los Angeles. Los Angeles is located in a climate zone that from 1877 through 2010 averaged slightly less than 15 inches of precipitation annually. The answer to my inquiry is fairly straightforward: Approximately 35 percent of L.A.'s potable water is from the Eastern Sierra Nevada watershed via the Los Angeles Aqueduct, about 11 percent is a result of mining regional groundwater, and around 54 percent started as snowfields in the Colorado River Basin and the central Sierra Nevadas and traveled almost 450 miles in canals and pipelines via the San Joaquin-Sacramento River Delta and the California Aqueduct (Villaraigosa 2008). It might be instructive for planners throughout the United States to think about what has happened as a result of water wars between the City of Los Angeles and landowners in Owens Valley in the Eastern Sierra Nevada. The answer is painfully obvious: Owens Valley has been sucked dry. The primary question that remains is: What part of Los Angeles' water supply can be thought of as environmentally sustainable now or in the foreseeable future? Perhaps readers should be thinking about Owens Valley and alkali dust storms (Reheis 1997).

Energy Consumption

If we engage in even a cursory examination of the role energy consumption plays in cities, data collected in 2009 by the U.S. Energy Information Administration (2010) reveals that nearly 80 percent of our energy was from fossil fuels, a little more than 8 percent from nuclear energy, and slightly less than 8 percent from renewable sources. And of the electrical energy produced in the United States, almost 50 percent of the national total is from burning coal. Because almost none of those fossil or nuclear fuels are produced within cities, the energy consumed by city dwellers is imported, leading to yet another massive environmental incompatibility with the concept of sustainability, not to mention the telling fact that a whopping 92 percent of that energy is from nonrenewable resources. Thus, sustainable energy remains an elusive sprite.

While on the topic of energy, Siemens, Cisco Systems, IBM, Living PlanIT, and many other firms are today locked in competition to build what they refer to as eco-cities that "can manage growth and development in a sustainable way that minimizes disruptions and helps increase prosperity for everyone."² In a similar movement, land investors proposed massive eco-developments in the mid-2000s for Abu Dhabi, China, Southeast Asia, the United Kingdom, the United States, and numerous other countries whose publicly stated goals were to re-shape the future by reducing or even eliminating the environmental costs of urban living through innovative use of technology. Planners might want to take those claims with a grain of salt or two, even for the relatively few projects that have made it off the drawing boards in these challenging financial times.

If Not Sustainable Cities, Then What?

Perhaps it is time for practicing planners to be honest with ourselves. Cities will never be environmentally sustainable, or eco-anything. To expect them to be is like expecting a pride of hungry lions on the Serengeti Plain to turn vegan and start rooting for tubers. That behavior is simply not in their nature.

What cities can and should be is less environmentally and energy profligate. In other words, they should be greener, smarter, more equitable, and better than the existing cities most of us practicing planners have had a hand in planning and building. Marking progress toward planning better cities should be our metric, not something as intellectually indefensible as environmental sustainability. As part of that metric, it is critical for all practicing planners, council members, and planning and zoning commissioners to realize that working toward better cities is a means to a more environmentally responsible future, not an end-state/goal that could be achieved in X number of years or even decades.

Planners and many others have long ignored the environmental aspect of the sustainability definition because that part of the tripartite equation — economy, society, environment — is the most difficult for modern North American culture to reconcile with our production-consumption lifestyles and deep-seated reluctance to give up the "In Growth We Trust" paradigm. Thus, the easy way out for planners has been to pretend we can have our cake and eat it too with sustainable cities that are supported by sustainable agriculture, as well as diverse and productive biological systems undiminished in geographic extent. As all real-world planners should know, the only place where that could happen is if we dive down the rabbit hole into the fantasy world of Alice's Wonderland.

As professional planners we know what cities are and perhaps have an inkling of what they might become if we keep our eyes open, our minds sharp, and our creativity levels high. As a first step, let's stop deceiving ourselves and faking it with city councils, planning and zoning commissions, stakeholders, and the public about what is possible and what is not. To say we can make cities environmentally sustainable involves smoke and mirrors and is intellectually unsupportable. To say we can help cities become environmentally less profligate and more economically and socially sustainable is on target and achievable. We should be talking about better cities, not sustainable cities. Deliberate obfuscation or misdirection should never be cards that planners play.

To move cities along the greener-smarter-better path, we must begin by getting directly involved in how much our individual cities can improve each year, each decade, each half-century. We have to think of practical ways to reduce energy consumption, find methods that will leave significant swatches of land in a quasi-natural state so at least some ecological values remain, and identify restoration projects that will result in more rather than fewer functioning habitats while improving biodiversity. Building more compact, denser, diverse, transit-oriented, walkable cities has little to do with environmental sustainability but has everything to do with creating urban places that are more environmentally responsible, more energy efficient, and more socially equitable.

Why Are Planners Myopic?

It may be instructive to reflect on why many practicing planners (and other urbanists) have been captivated by the myth of sustainable cities. Much like Plato's allegory of the cave, where chained prisoners mistake shadows on the wall in front of them for the reality behind them, something has prevented planners from turning around to see the reality. Perhaps the enticing shadows of the continued and often comforting cycle of production-consumption have mesmerized us. Perhaps the real-world difficulties of confronting the powerful political structure involved in the "In Growth We Trust" paradigm have played an avoidance role. Perhaps it is something we desperately want to believe in and so we do. In any case, a quick scan of Internet sites that delve into the topic of "sustainable cities" should be sufficient to demonstrate the myth's pervasiveness in urban planning circles, even in numerous academic departments that perhaps should have conducted a more intellectually rigorous analysis before jumping on that bandwagon.

Planning Without Sustainable City Rhetoric

In a way, I have saved for last the most important and practical rationale for abandoning the untenable sustainable cities concept. A critical incentive to never use the word sustainable, or any of its variants, with reference to cities, is political ideology. Many political conservatives hold dear to their hearts sentiments that Pirages and Ehrlich (1974, 43) defined as the Dominant Social Paradigm (DSP), or what many today identify with conservative (free market) environmentalism. At the risk of oversimplification, I'll define the DSP as a system in which human domination over nature is regarded as the natural order; resources are believed to be enormous and will provide unlimited opportunities for humans; technological progress makes all, or almost all, problems ultimately solvable; and traditional economic growth is both morally good and sustainable (Rees 1997, 303). On the other side of the ideological divide is what social ecologists have identified is the New Ecological Paradigm (NEP), which can be summarized briefly as the continuance of human civilization depends on the survival of natural systems (Catton and Dunlap 1978, 1980).

Given that cities have a mix of voters aligned with both political ideologies as well as a great many people located somewhere between those polar positions — and also because a significant proportion of planners take issue with the DSP and conservative environmentalism — it behooves practicing planners to remove what threatens to become an enormous bone of contention from the public arena. We can do that by forgetting we ever heard the term "sustainable cities" and by focusing on environmental values people of all political persuasions share and support. Those shared values include saving money by cutting energy and infrastructure costs via techniques like low-impact development, breathing fresh outdoor air, swimming in clean water, catching fish that are not laced with chemical poisons, bringing back wildlife diversity, restoring wetlands and riparian systems to more natural states, or improving urban parks by planting only indigenous species and systematically removing invasive and exotic flora and fauna. Even the most ideologically committed citizens are unlikely to advocate wasting taxpayer dollars on unnecessary energy or infrastructure projects, or to reject efforts that would result in more native trees and shrubs and thus bring more birds, bunnies, and butterflies to our parks and backyards. After all is said and done, it would be difficult to find people who would be vociferous opponents of improving everyone's quality of life by building better and more environmentally responsible cities.

But using the word sustainable to describe what we plan to do can cause political temperatures to rise and tempers to flare until we run the risk of having citizens no longer talking to each other but yelling across a growing divide (Hoffman 2011a, 2011b). As practicing planners we should be aware that not all environmental regulations are workable just like not all free-market environmental solutions are unworkable.

It should be noted that tolerance for competing or conflicting viewpoints has its own set of difficulties, especially when closely held value systems are in conflict (Phillips 2003, 5). A number of researchers believe that little progress can be made on critical social issues without rational public debate and conflict (Cobb 2000, 2). Advocacy and community-based planners who acknowledge their actions are not value-neutral surely have played powerful roles in advancing social positions in planning, as was illustrated by Davidoff (1965). But, the difficulty with advocacy, as Cobb (2000, 25) noted, is as soon as people begin spouting "scientific facts" in support of a specific ideological position, those facts themselves become politically tainted and can easily be rejected by individuals and groups who oppose that position.

It is my contention that political differences can be moderated without significant disagreement when planners decline to support either side of what could become an environmental argument and instead emphasize shared values. Keeping our dialogue as free from ideological conflict as is possible while discussing shared environmental values — such as turning to low-impact development and green infrastructure to reduce the cost of stormwater drainage — avoids the ideological divide and is surely a step in the direction of responsible environmental action. Another of those first steps in that direction should be to throw the term "sustainable cities" into the trash bin in the move toward a more pragmatic, yet better and brighter urban future.

Conclusion

I want to conclude this discussion by referring to a highly significant issue concerning cities and environment highlighted by Rees (1997) that practicing planners should never overlook or devalue. Planning efforts to green our cities can only go so far since ecological footprint is largely determined by individual consumption rather than by urban form and pattern, the built environment, or institutional function. Consequently, if practicing planners want to be at the forefront of building more environmentally responsible cities, they must be directly involved in community outreach efforts that focus on educating the general public with respect to putting shared environmental values into action and to the significance of those actions regarding the future of cities and their inhabitants.

As Arie de Geus, the well-known organizational learning specialist (1988, 70) who also served as Dutch Royal Shell's corporate Coordinator of Group Planning, perceptively noted, "... planning means changing minds not making plans." Therefore, both practicing and academic planners must be creative about how to begin changing minds, including our own, as we plan more environmentally responsible cities.

Robert Ernst, who has a PhD in geography from the University of Florida, is a specialist in land-based systems, including comprehensive urban and regional planning, policy/strategic planning, urban re-development, economic development, land use, and environmental impact studies. His nearly 40 years of experience includes managing large-scale assignments involving multi-disciplinary teams, and devising and implementing public involvement strategies. He has provided consulting services to local political jurisdictions; regional, state, and federal agencies; foreign governmental agencies; and private land development and natural resource firms in the United States and overseas. Ernst recently retired and lives with his wife in the St. Louis metropolitan area.

Notes

1. www.planning.org/policy/guides/adopted/sustainability.htm

2. See IBM website: www.ibm.com/smarterplanet/us/en/smarter_cities/overview/index.html; also see the Siemens website: www.usa.siemens.com/sustainable-cities/?stc=usccc025099

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