Monday, July 27, 2009

We are stewing in our own oven


Sydney Morning Herald, July 27, 2009

You, reader, live in a primitive city. In a hundred years from now, the society we are building will look back and marvel at how little we really understood about the world we have constructed for ourselves.

We are stewing in our own juices.

Last Wednesday, a night of driving rain, I attended a seminar where more than 100 professionals, a standing room-only crowd, had gathered to learn about practical, cheap, achievable ways of stopping Sydney's pot from simmering. These were not wide-eyed utopians. In purely parochial terms, the heating of our biggest cities is even bigger than the global warming debate. Because the rise in temperature is mostly and demonstrably caused by outdated thinking.

The story starts on Observatory Hill, at the southern end of the Harbour Bridge, where weather records have been kept daily since 1860. What the observatory has recorded is a rise in the average temperature at the centre of Sydney from 20.5 degrees to 22 degrees. As Sydney grows, Sydney slowly heats.

At last Wednesday's seminar we learnt why - 27 per cent of the surface of the metropolitan area is covered by bitumen, the black tar which soaks and retains heat and thus changes the city's climate.

Nearly all the rainwater run-off on this 27 per cent of the city is lost to productive use, flowing into Sydney Harbour because it is designed that way. The city's rooftops also gather heat. Roads and pavements maximise the waste of arable land. Tree-planting is stunted for legal reasons. Topsoil is "scalped" by roadworks. The increasing use of air-conditioners is creating more energy. More heat begets more heat.

It is not just a Sydney story. The most telling detail lost amid all that was written and broadcast about the Black Saturday bushfires in Victoria, which killed 173 people, was that more people died from heat stress in Melbourne than in the fires. During the oven-like temperature peak (three consecutive days above 43 degrees) Melbourne saw a spike of 1400 emergencies requiring an ambulance.

An extra 374 people died in Victoria that week compared to the average week. Most were heat stress related.

"To break this heating cycle we don't need more money, we need more intelligent use of what we already have," says the person who organised Wednesday's seminar, Michael Mobbs, the creator of Sydney's most famous experiment in sustainable housing. He was stunned by the size and quality of the turnout. The room was full of planners from councils across Sydney. He was especially pleased that the gathering was addressed by Arjan Rensen, a senior executive from ARRB, the company which writes the specification guidelines for all the road agencies in Australia.

"It was hugely symbolic having him there, willing to be associated with what we're trying to do," Mobbs told me. "It means the road authorities are at last starting to deal with the impact their roads are having on our cities."

The roads are Mobbs's starting point for reform, because they take up so much room and are so taken for granted. "We should just use existing bitumen and gravel but choose pale gravel, and mix it so that the gravel shows through the bitumen," Mobbs says. "We could also use dyes like those used in bus lanes, but paler than green or red. These were first used in the Harbour Tunnel, which was privately owned, because the owners wanted to cut the cost of their electricity bill. On streets with low traffic volume, these dyed surfaces will last 15 to 20 years."

Then there is the overlooked space, the humble pavements. They should be planted and widened where possible because of the cooling powers of plants and trees. Fruit trees and vegetable gardens should also be grown in public space such as roadsides. The practice is common in Germany.

Planners have started listening to Mobbs because, having transformed his own home into a dwelling with self-contained power, water and sewerage systems, he is busy converting his street, Myrtle Street, Chippendale, into the sort of micro-environment that, if replicated across the city, would cool it, slash energy consumption, and massively increase carbon sequestration.

In the block where Mobbs lives, much of the pavement is covered in mulch and supports a variety of plants, including fruit trees. The fruit is available to anyone. Large public compost bins store debris, each collecting three tonnes of food waste a year to create one tonne of compost. Pipes have been manipulated to retain rainwater run-off.

All this is so simple yet so innovative. Councils and planners have been trying to do their best with what they have inside a system they have inherited. What has been lacking is a sense of the whole, of the potential for policy symbiosis, a greater realisation of what Sydney looks like on Google Earth rather than on planners' maps. Google Earth shows a city that acts as a heat trap and an energy sink, especially in the sprawling, spreading western suburbs, away from the cooling salvation of the coast.

But when I asked Mobbs if he had received council approval for his innovations on public space on Myrtle Street he replies, "not quite".

The local authority, Sydney City Council, has an ambivalent attitude. It is on his side but it is also a bureaucracy operating under the morass of laws and regulations that sits like an oppressive weight on innovation in society. Says Mobbs: "It's all been done with the delicious sense of doing something without approval."

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