Monday 5 March 2007

China's ecocities an inspiration

Canberra City News
Thursday 1/3/2007 Page: 22

CANBERRA and other capital cities are not the only modern cities to be custom built and designed. China, for example has no less than 11 custom-built "ecocities" - cities designed to minimise greenhouse gas emissions and water use without sacrificing comfort and convenience.

Of course, given the population of China, 11 cities is not nearly as significant to most Chinese as they would be to Australians if placed here. Nevertheless, they represent a view of the future, and developers around the world are looking at projects such as these for development ideas.

Engineering firm Ove Arup (UK) is building one such city - Dongtan Eco-City on Chongming Island in Shanghai with Peter Head as the project director. On a recent visit to Australia where he was a guest speaker at the Green Cities conference jointly hosted by the Green Building Council and the Property Council of Australia, he described the project. First he expressed the view that going green is no longer an option, but a necessity.

Head said the levels of carbon dioxide in the world's atmosphere are already critical, approaching around 360 parts per million-an unprecedented level. The best future outcome, he said, is CO2 levelling out at around 500 parts per million and even so it will be extremely hard to stop the concentration rising above that figure. And every new building that isn't green will make it harder.

Some nations are building at a phenomenal rate. China is one. "The big challenge for the world," said Head,"is whether China and India can extend their GDP growth without extending their CO2 emissions". China's current development is ecologically unsustainable, said Head, but Zhenhua Xie, the Minister for the State Environmental Protection Agency, has a 10-year plan for a greener future, with Dongtan as part of it.

The new city's site is 8400ha (84 sq km), and its first stage, due by 2010, involves a 30km road/rail link to the mainland. "It is one of the largest crossing projects in the world," said Head. Dongtan was designed around a concept of "integrated urbanism"; a true city, but displaying compelling green features.

Most cities can't support themselves, environmentally speaking, and they have to import food water and power. All of this takes up space to produce and resources to transport to town. The average amount of world resources taken to keep people in power, water and food, is measured in global hectares per person. The average across the world is 5.5. Dongtan will supply the city's needs on just 2.6. "We wanted 1.8," said Head ruefully. But even so it's a considerable step in the right direction.

This was a project for a private developer, the Shanghai Industrial Investment Co, so it also has to make money. Dongtan looks like achieving both targets. Of course the individual buildings will be designed for maximum energy efficiency. But the city as a whole is designed for green results.

The city comprises three municipal villages, all with green roofs on the buildings, parks and areas with water features. Greenleaf vegetables are grown in the city itself. All municipal industrial waste will be recycled so there is no need for landfill space. The compact, mixed-use design means residents don't have to travel far to work. There will be around 75 dwellings per hectare, and the average building height will be 4-8 storeys.

The city has three flood mitigation systems. It also creates micro-climates - placing and orienting buildings to ensure shade and sun at the right times and provide comfortable temperature and humidity levels. Water will be recycled, and discharged water is expected to be reduced by around 80 per cent over normal levels.

Wind patterns were mapped and windfarms on the edge of town will be positioned where the wind is high. There are to be solar panels on the rooftops and a biomass energy centre producing two thirds of the energy supply.

Total energy demand will be reduced by 64 per cent over normal levels. The town motto? "Better city. Better life." Not a bad motto for any city. We in the property industry will follow progress on Dongtan and other ecocities with much interest.

Catherine Carter is executive director of the Property Council of Australia (ACT)

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