No one knows what a sustainable city looks like because there has never been one. Cities have always been built on gross exploitation of the surrounding environment – that’s the way they work. Ancient Rome began its existence with the construction of an enormous sewer called the Cloaca Maxima, ancient Uruk turned its’ part of the Euphrates river valley into a cement salt pan. The principal difference between cities today and the ancient ones is the speed and size of their growth.
Prior to the second half of the 20th century, the earth’s capital reserves of clean air, clean water, energy etc. were so vast that the urban effusions were no more than a few pimples on the planet’s skin. Cities are now so populous, (there will soon be a Chinese city of 46 million) that those small stains have turned into the planetary equivalent of small pox and are now eating into the planet’s vast capital accrued over millennia faster than the capital can be replaced.
So if we want cities to continue, they must learn to do something entirely novel – as they grow, they must take less from the planet, not more. Since this has never been done, it’s no wonder neither politicians nor people can imagine what a city like this might look like, but we have intimations.
A sustainable city would be one where a new arrival at the Ottawa airport would not be greeted by a brand new, 2,000 slot parking lot and a warehouse building called an exhibit centre. This is not reducing the Ottawa environmental stain as we grow. This is expanding it. Reducing it would have the city’s visitor find electric light rail at the airport ready to take the new arrival to the city centre and he or she would see from the train window what was there before the parking lot arrived, a green wetland forest – only better managed.
A city that is sustainable would look and feel like a place that as it grows reduces its environmental stain with less cars and less asphalt, not more. There would be more pedestrians and cyclists, not less as the city grows. There would be a rich local farming community capable of feeding the city and ancient forests like the South March Highlands would be cherished, not razed.
None of this is happening in Ottawa, but it is in some cities where they are beginning to give us intimations of what a sustainable city might look like.