Note: this post is a version of an article published in the journal, Practicing Planner, in March, 2012.
Over the past
several decades, planners have been exposed to the concepts of sustainability,
smart growth, green cities, etc. from numerous sources, the greater majority of
which were created by urban and regional planners and landscape architects
(McHarg 1969; Godschalk & Parker 1975; Spirn 1984; Rees & Wackernagel
1996; Innes & 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 & Dickson 2003) and on how those interactions affect the
challenge of sustainability (Reitan 2005). In addition, many universities have
established sustainable cities centers or initiatives, e.g.,
Stanford University,
University of
Oregon,
and
University of
Kentucky among numerous others.
In addition, cities throughout the U.S. have also adopted sustainable
initiatives, e.g., Seattle, Portland, Austin, Boston, and Jackson, Mississippi,
to name but a few. 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.
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).
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 the 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 larger than the area of the U.S.
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 or expanding cities destroyed or degraded
almost beyond recognition the environments that had been extent and built
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).
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
throughout the world and off the coast of Louisiana (Rabalais et al. 2010).
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
many 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.
It is also
important to explore, at least briefly, how urban water and energy supplies fit
into the current conception of sustainable cities. Since 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 LA’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 U.S. 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’s 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).
If we even engage
in 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 over eight
percent from nuclear energy, and slightly less than eight percent from
renewable sources. And of the electrical energy produced in the U.S., almost
50 percent of the national total is from burning coal. Since 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 non-renewable 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.”
In a similar movement, land investors proposed massive eco-developments in the
mid-2000s for
Abu Dhabi,
China,
Southeast Asia,
United Kingdom, the
U.S., 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.
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. The problem is 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 (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, P & Z 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, 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.
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 a group of chained prisoners mistook shadows on the wall in front
of them for the reality that lay behind, 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 power 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.
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).
Since 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 since 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 more birds,
bunnies, and butterflies in 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 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 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.
I want to
conclude this discussion by referring to a highly significant issue concerning
cities and environment that was 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.
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