Building the dream

Construction of the world's first 'eco-city' is to commence later this year in Shanghai. But it is founded on immense complexity, and faces great challenges. Elius Levin reports from China

UK-based engineering firm, Arup will begin Phase One of the world's first 'eco-city' in Shanghai later this year. To be developed in four stages, the first phase will be a demonstration project for the 2010 Expo. The entire project will take 34 years, with an anticipated housing capacity of 50,000 by 2010, rising to 500,000 by 2040.

The chosen site is Dongtan on Chongming Island in the Dongtan Peninsula. It is on the mouth of the Yangtze River, and about a one-hour ferry ride from Shanghai. Presently comprising about 630 hectares of vacant farmland and a basic road network, Dongtan eco-city is itself part of more ambitious plans to be rolled out by 2010 and beyond. These plans - as part of the combined effort of the Chinese national and Shanghai municipal governments - include the development of thousands of square kilometres of the mouth of the Yangtze, along with the building of a deep-sea harbour for Shanghai some 30km out in the East China Sea.

Though responsible for the master planning, Arup has gone considerably beyond this. "We have undertaken an integrated-urbanism approach," says Design Lead, Alejandro Gutierrez. "This incorporates design, economic feasibility, ecological footprint analysis and engineering feasibility, among others."

Gutierrez also recognises that with such projects, the factors of time, cost, client changes, as well as the level of expertise and technology available at the time of construction will likely see changes along the way. For the Chinese authorities, motivation is fuelled by a complex mix of sharp pragmatism and severe hand-wringing.

As part of larger national housing plans to 2020 for 400 million, Dongtan eco-city illustrates the authorities' attempt to more effectively manage both population and the full spectrum of its concomitant requirements. Saddled with some of the most polluted cities in Asia, international headlines of recent environmental catastrophes serve only to reinforce the Government's great concern.

While some commentators have pointed out such accidents occur more regularly than reports suggest, the outbreak of protests in rural areas in recent months and the Government's brutal reaction indicate both its traditional response, and its growing impatience and desperation. Dongtan underlines the Government's recognition that its development-at-all-costs policies of the past are catching up with it.

The first of reportedly three eco-cities currently being planned, a project of this size is not without problems. "There are many difficulties - political, technical, legal," says Gutierrez. For its part, as steward in seeking to realise this urban ecological icon-in-the-making, the Shanghai government must parry two daggers of controversy.
Firstly, Chongming Island is currently home to the Dongtan Protection Zone bird sanctuary, set up by the Shanghai Municipal Government in 1998, and stopover migration point to nearly three million birds, including the hooded crane, an internationally protected and endangered species. With reportedly 10,000 hooded cranes worldwide, China promulgated the Wild Animal Protection Law in 1981. While Dongtan Protection Zone is one of four such zones the authorities established, it increasingly appears that such habitats are set aside for development.

Secondly, the development will severely affect the current island inhabitants. Formed by the continued silting of the Yangtze estuary, and comprising mainly farmland, Chongming Island has provided a way of life for its present two million peasant inhabitants, whose agricultural produce feed Shanghai.
It is still unclear as to whether or not these farmers will be relocated. If so, the great probability of inciting riots so close to the metropolis, and under the watchful eye of the international community, will likely deter potential investors and severely damage the economy as a whole. If not, the farmers will find on their doorstep a captive market for their organic produce.

Difficult path to low EF
rup's "integrated urbanism" (IU) is chiefly based on urban ecology (UE), which incorporates four disciplines:
    Architecture
  • Urban design and planning
  • Engineering
  • Ecology
UE is founded on the overall principle that properly-conceived and designed, a city or any urban setting can provide a healthy, low or non-polluting environment, creating
better quality and managed communities. Often, specific urban problems, for example waste management or habitat rehabilitation are examined. Within UE, a city is viewed
as an ecosystem, possessing cycles of matter and flows of energy through a system - each comprising an overarching and numerous sub-systems - consisting of complex interactions of plants, animals and humans, both with each other and with their environment in urban settings.

To make Dongtan energy self-sufficient, Arup has proposed that residential and commercial buildings be powered by a combination of wind, sun and other renewable energy sources. All electric and hydrogen-cell cars are to be the main forms of transport, and, where possible, the community is to be self-sufficient in organic food. It will provide fully integrated urban living, including light industrial and high technology employment, recreational and residential facilities. Dongtan is the "most aggressive expression of
sustainability" to date, says Urban Strategy Leader, Gary Lawrence.

Great complexity is required in order to determine Dongtan's energy flows, the measure of sustainability, and grapple with the city's particular problems. Vast teams of experts and extraordinary computing power are utilised.
Grouped like departments in an organisational chart, but distributed in numerous locales in and outside of the UK, each team comprises
a different mix of experts working collaboratively, such as sociologists, engineers, economists, environmental physicists and others.

Ecological footprint
Each team draws on its company historical data. Computer simulations or models are used in calculation and evaluation of the interactions of different design variations, later adding in and evaluating social, technological and economic factors. These are then examined against the primary sustainability measure, the ecological footprint analysis (EFA), which measures the amount of renewable and non-renewable ecologically productive land area required to support the resource demands, and absorb the wastes of a given population or activity.

In terms of sustainability, when any given site or project exceeds the amount of renewable energy and natural forces able to sustain it, a deficit in natural capital occurs, resulting in an unsustainable environment. EFAs can thus be determined at the level of an individual, a house, a suburb, a city, or a nation.

Globally, there are about 4.5 acres (1.89 hectares) available for each person, which is
calculated by dividing the total amount of ecologically productive land area by the human population. Presently, the world's Ecological Footprint (EF) appears to have breached ecological limits and is thus unsustainable.

For example, comparisons can be made between the area required for residential versus commercial areas, the amount of energy each requires and uses, and the amount of air pollution each area causes. Add to this the amount of people, cars, buses, food transported and consumed, electricity and oil required and utilised, and a picture readily forms. From this, a varying EF is determined from the variation in densities or distances between buildings, grouping and location of buildings, building materials, numbers of people, and the influence on and by heat, wind and so on.

For Dongtan, Arup aims for a global EF of 2.2 hectares per person. This is to be achieved by "going back to small urban areas", says Gutierrez, and "having much more land close to the city", presumably signalling the end of the sprawl - a fundamental problem of contemporary cities.

Cleaner water
For Phase One, there are problems such as capturing and purifying the water. Providing the main source of water, the Yangtze River is, like many of China's rivers and lakes, heavily polluted. Though its location in the delta provides it cleaner water, Arup will use a combination of recyclable permeable membrane placed on the ground to capture rainwater and precipitation, and implement passive desalination.
Climate-wise, Arup must create a disaster-resilient community, which must be capable of withstanding typhoons and be able to recover quickly. A proposed light-rail grid to transport residents between Shanghai and Chongming has been proposed, while some reports indicate the car will be the primary transportation means.
Electric or not, a central tenet of eco-cities is the focus on walkability and community. Will the Chinese authorities opt for compromise, to aid and abet their auto industry, providing a city with sustainability trappings, or fulfil the promise of a true eco-city? Will Dongtan illustrate "sustainability moving from best practice to common practice" as Lawrence suggests? Very careful calculation of the odds might provide an answer.

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