By Steve Schifferes
Globalisation reporter, BBC News, Shanghai, China
Prosperity has brought mobiles - but many still cycle to work
Shanghai has been transformed into a global city - but its rapid growth has produced pollution, traffic jams and overcrowding.
In becoming one of the centres of the world economy, Shanghai has grown faster than almost any other global city in the past 15 years.
The population increased from 13.5 million to 21.5 million as migrant labourers flooded in from the surrounding countryside, and the standard of living rose even faster, with per capita income now at $7,000, the highest in China.
The physical size of the city increased sixfold, from just 100 sq km to 680 sq km, as people sought more space and the city government rushed to develop nearby areas, such as Pudong.
Rapid growth of car ownership has led to congestion and pollution
Three ring roads and six motorways now criss-cross the city, and gridlock grips the bridges and tunnels across the Huangpu river during rush hours.
The city has also seen an explosion in car ownership, with over 1 million car owners in 2006, and private car ownership has doubled in two years.
The increased traffic levels contributed to rising levels of atmospheric pollution.
Now the city of Shanghai has begun to tackle some of the environmental problems that could threaten its future growth.
Building new towns
Despite its size, Shanghai is still much more densely populated than Western cities, with four times more people per square kilometre than New York.
Overcrowded accommodation in the centre is being replaced
And according to Michael Kwok, head of the architectural consultants Arup in Shanghai, there is very little land left to build on in the central city, after a decade of rapid development.
So Shanghai's planners want to limit population growth in the centre by building satellite towns in the outskirts.
Like the UK's New Towns, constructed not long after World War Two to disperse population out of London's most overcrowded districts, the idea is to provide cheaper housing and jobs to attract people to leave congested areas.
Under Shanghai's "One City - Nine Towns" plan, Shanghai is planning nine new cities which will eventually house 500,000 people each.
Six of the cities are themed to look like European cities, including the UK, Germany, Italy, Spain, the Netherlands and Sweden.
Rich Shanghai residents prefer faux London in the suburbs
Thamestown, which opened in October 2006, has themed pubs and Tudor-looking architecture concealing high-rise blocks.
But critics say that so far, most of the housing built in such towns is out of reach of ordinary citizens.
And they argue that the cities have so far not created enough jobs to prevent most residents from commuting into Shanghai, adding to transportation pressures.
Discouraging car ownership
Shanghai has made it expensive to own a car in the city.
The city sets a strict limit on the number of licences it will issue for private car ownership - currently around 80,000 per year - and then auctions them off..
With the high demand for cars, the current cost of getting a car license in Shanghai is over 40,000 yuan ($5,500; £2,750).
However, a significant factor in Shanghai is the use of cars - and minivans - by private businesses.
Over half of all cars in Shanghai are owned by companies - who are less sensitive to financial constraints.
Investment in public transport
The modern metro carries 1.8 million a day
According to Professor Chen of Tongji University School of Transportation Engineering, the city is now investing heavily in public transport.
Since the mid-1990s, it has built an extensive metro system, with five lines, now used by 1.8 million people per day, and it is now planning six new lines.
If it carries out all its plans, the length of the system will exceed London's, the world's biggest.
Buses and the poor
Overall, one-quarter of journeys in Shanghai are by public transport, and the city would like to increase that to 30% by 2010.
Private bus companies have proliterated in Shanghai
According to Professor Chen, that will mean boosting the numbers who ride the buses as well.
Shanghai has more than 1,000 bus routes, run by a variety of private bus companies, but the system of interchanges between lines is confusing and expensive.
She has convinced the city that it should make all transfers free in order to encourage more people to ride the system.
Bicycles and scooters
Despite the spread of car ownership, two-thirds of private journeys in Shanghai are by two-wheeled vehicles such as bicycles and scooters.
Bicycles fight for space with pedestrians and cars
The city has already banned larger motorbikes, and has introduced restrictions on bikes on the many commuter highways in the city.
But it is also building 180km of dedicated bike lanes, especially in newly built areas like Pudong, where bicycles will be segregated from scooters.
Affluence and growth
Shanghai has had some success in tackling its environmental issues.
Glossy ads for Western fashion dominate shopping districts
One fact has been a strong planning system, coupled with the fact that the government owns all the land.
This has allowed the rapid redevelopment of the city and its infrastructure - as well as generating money to pay for big infrastructure projects.
Air quality has improved with unacceptable days dropping from 20% to 10% in the past five years.
But water pollution, is worse, as the rapid growth of industry in the Shanghai region, upstream of the city, has made it harder to keep the city's main water source, the Yangtze River, clean.
The city's speed at developing its infrastructure has also come with a human cost, with millions of people displaced for public and private building projects..
According to Michael Kwok, in the early days of Shanghai's development it was relatively easy to relocate people to outlying areas, but now people are demanding more compensation.
More broadly, Shanghai is the still the embodiment of China's economic dream of living in an affluent society on a Western scale.
Those aspirations - for more land and housing, as well as more consumer durables like cars and air conditioners - are likely to put further pressure on Shanghai's environment in the future.
This is part of a series on how globalisation is changing China's largest city, Shanghai. Further articles will explore the issue of migrant labour and look at plans for an eco-city.