Have you ever wondered, out of curiosity, what the least sustainable city on earth might be? In writing his book about sustainable cities, Professor Andrew Ross of New York University didn’t go looking for good examples. He wanted to document the worst he could find, because if that place could transition to a sustainable future, then it would be it be possible anywhere. The book is called Bird on Fire, and the city is Phoenix, Arizona.
Phoenix has an interesting story, because the city that stands in the Sonoran desert today is not the first settlement to be built there. The Hohokam people were there first. Uniquely among North American tribes, they were canal builders, and built a large network of canals and weirs to irrigate their notoriously dry homeland. In the Middle Ages, these canals allowed the Hohokam to settle, farm, build sizeable towns, and establish trade routes with their neighbours.
The project did not last. The population grew and began to strain at the ecological capacity of the region. A series of droughts made things worse, while floods upstream destroyed vital parts of the canal network. By 1400 the Hohokam had abandoned the land and their adobe walls eroded back into the desert. The ruins of their largest town can be visited at Casa Grande National Park.
The original canals were rediscovered in the 1860s, and pioneers dug them out again. Knowing that they were building on the ruins of an ancient predecessor, the early residents chose the name Phoenix. It was at first a small farming town, then became a trading post with the arrival of the railway. New dam projects increased its water supply and made new growth possible, and in 1912 it became the state capital.
In 1947 an unfortunate incident occurred which had serious repercussions. There was a fire at the streetcar depot. Most of the fleet was destroyed, and rather than build a new public transport system to replace it, the city decided to focus on cars instead. Streets were widened, suburbs were built without tram connections, and the scene was set for urban sprawl.
Drawn by the year-round sunshine, those suburbs continued to grow. In more recent years, new housing developments have been the main source of growth in the city. The cotton fields and citrus orchards that used to be important have been turned over to development and the sprawl now covers well over a thousand square miles. Population has boomed, growing by a quarter in ten years. Predictably, the city suffered particularly badly from the sub-prime housing crisis.
Today greater Phoenix has a population of 4.3 million people, but it’s still in the middle of the desert. That desert is very slowly getting hotter and drier as the climate changes. The city depends on water pumped 300 miles from the Colorado River, which is itself depleted by overuse and long term drought. Besides the obvious challenges of water, Phoenix has very high CO2 emissions and notorious air quality. It also has a staunchly anti-green political culture. It’s hard to say if it’s absolutely the least sustainable city on the planet, but it’s certainly a contender.
It would be easy to condemn Phoenix as an environmental lost cause. It probably shouldn’t have been built in the first place, and the existence of a ruined civilization on the same spot should have been a warning rather than an invitation. But it’s not as if 4.3 million people can just be moved and the place bulldozed, so the question of transitioning Phoenix to a sustainable footing has to be seriously examined. It’s not really good enough to say it can’t be done.
Nobody needs to examine that question more than Phoenix itself, and the signs are pretty mixed. A ‘Re-invent Phoenix‘ scheme is re-orienting development along light rail corridors, although I note that it is still a growth strategy. Water conservation measures have reduced per capita consumption by 20% over the last two decades, but those savings have been entirely overtaken by the growing population. You’d have thought solar energy and particularly solar thermal ought to be a no-brainer in the Valley of the Sun, but apparently the city’s stated renewable energy target is a pathetic 15% of electricity generation by 2025.
There is huge potential for infill development on abandoned lots and brownfield sites, creating a denser city – something Detroit has tried. Building codes are being improved to encourage walking and cycling, and there are many opportunities for urban farming too. In one of the more interesting developments, the Gila River Indian Community won a court case that granted them a third of the city’s Colorado river rights, and they are using the water resource to raise local food production.
I would need further convincing before declaring that Phoenix could ever be made sustainable, starting with a dramatic change in political culture and public awareness of environmental issues. But I do respect Andrew Ross’s sentiment in studying the city: “We don’t just live in the success stories”, he says. “Much more vulnerable and even recalcitrant cities have much more to teach us about whether we have the wherewithal to make changes.”