Definition: There are
several ways to define sustainability.
One, attributed to the “Brundtland Commission” considers sustainability
to be the ability to satisfy current needs without compromising the ability of
future generations to meet their needs.
This definition rests on intergenerational equity. The second generation focuses on equity at
the current moment, and holds the needs of classes, ethnic groups, or nations
who are less empowered, to have a legitimate stake in the satisfaction of
needs. A third definition can also be
identified. It focuses on the capacity
of people to live within the capacities of ecosystems to support them.
This, in a sense, is the most fundamental definition of
sustainability. It hews very close to the
ordinary definition of sustainability in the sense of sustenance or
support.
Examples: Applying
the concept of sustainability to urban systems requires some caution. From an environmental standpoint, no urban
area is strictly sustainable. Large
urban areas, including suburbs, and their non-agricultural exurbs, do not
supply their own food, cleansing capacities, or other environmental benefits
(see Ecosystem Services). However, city,
suburban, exurban systems that contribute toward their food needs,
environmental cleansing, carbon storage, and pollution reduction, for example,
can be said to be more sustainable than those which do not make the same kinds
of contributions. Urban sustainability
is thus a relative condition.
 | ||
| Sustainability has three components: environmental, social, and economic. There is benefit to achieving sustainability in each realm, and the overlaps between each pair also has value, as noted by the grey boxes. However, true and lasting sustainability can only result from the overlap of all three areas. In other words, sustainability in any one area—environment, social, or economic—without attention to the other two will ultimately fail. |
Why important: No
activity that claims a benefit to sustainability can be narrowly
construed. All definitions of
sustainability from the 1980s on, recognize that sustainability has three
inextricably linked components – economic, social, and environmental. Thus, people often speak of a “triple bottom
line” in making any decision, so that the health of the economy, of the
environment, and of social equity are all supported by decisions and actions
that enhance sustainability. None of the
three aspects of sustainability trumps the others. Given that urban sustainability is a relative
condition, there are many activities and strategies cities, suburbs, and
urbanized exurbs can make toward sustainability.
For more information:
Williams, D.E. 2007. Sustainable
Design: Ecology, Architecture, and Planning.
Wiley, Hoboken NJ.
Curwell, S., M. Deakin, and
M. Symes, editors. 2005. Sustainable urban development, volume 1: the framework
and protocols for environmental assessment. Routledge, New York.
