Our most livable city will remain one of the least sustainable on Earth unless .
Date: Wednesday, November 16 2005
Livability isn’t sustainability
By william e. rees
Publish Date: 27-Oct-2005
The world is experiencing the greatest human migration in history. This is a rural-urban migration that has swelled the population of the world’s cities 50 percent to three billion in the 1990s and is expected to add another 2.2 billion people to those cities by 2030. This means that in just three decades, the urban population alone is expected to grow by the equivalent of the total human population in the early 1930s! And most of this explosive growth will take place in the poorest of cities, adding millions of people to their already swarming, squalid slums.
All this raises a critical question: in an age of alleged “sustainable development”, just how sustainable are the world’s cities, both rich and poor?
To some analysts, this question is silly, even meaningless. They argue that people come to cities to take advantage of economic opportunities, to better themselves. The barrios may be social disasters, but such slums are temporary, a transitional phase that will be eliminated by economic growth. Just look at the seeming wealth creation that has lifted so many Chinese cities from the mire of poverty in the past quarter-century.
Appalled by pollution? No problem! Once people get rich enough to care about air and water quality, they’ll deal with it. In the words of economist Wilfred Beckerman, “the surest way to improve your environment is to become rich”. Worried about resource shortages? No issue here either, now that technology can substitute for nature and thus decouple the economy from the ecosphere. As Nobel-laureate economist Robert Solow famously put it, “If it is very easy to substitute other factors for natural resources, then…the world can, in effect, get along without natural resources, so exhaustion is just an event, not a catastrophe.”
But is it really that easy? Can economic growth and technological prowess really fill all the potential potholes on the road to sustainability? Maybe not, if we look more closely at the biophysical and ethical dimensions of the problem.
First, what do we mean by sustainability? On the simplest level, something is sustainable if it can safely remain in its present state or maintain its present course indefinitely. Thus, a sustainable society might be one that is experiencing positive social, cultural, and economic change—i.e., development—that does not degrade the ecosystems upon which that society is dependent. Note that development as defined here can occur with or without growth in the scale of the economy.
But how can we determine whether or not a society is overusing its critical ecosystems? By using ecological-footprint analysis (EFA), a quantitative tool I have pioneered with my students at UBC. EFA estimates the area of average land and water ecosystems required, on a continuous basis, to supply the resources consumed, and to assimilate the wastes produced, by any specified population, wherever those ecosystems are located.
It turns out that the residents of the world’s rich cities require five to 10 hectares of productive ecosystem per capita compared to the half-hectare needed by the poorest of the poor. By this measure, in 2001, Greater Vancouver’s 2.1 million residents had an aggregate eco-footprint of almost 14 million hectares. This is 48 times the size of the Greater Vancouver Regional District, or about 20 times the area of the entire lower Fraser Valley, from Hope to the sea.