In the past city waterfront developments have tended to follow the environmental Kuznets curve: a U-shaped curve showing how rising GDP is associated with a fall in water quality at first, followed by a rise later. "The community develops and pollutes up to a certain level before society demands, and is willing to pay for, pollution reduction and remediation," explained Derek Vollmer, from the National Academies Science and Technology for Sustainability Program in Washington DC, US.
The classic example of this is the Cuyahoga River in Northeast Ohio, US. Its black oily surface used to frequently catch fire. Finally a major fire in 1969, 101 years after the first river fire, precipitated a big clean-up. Today the waters are clear and much of the river is thriving, supporting up to 44 different species of fish.
For most of the industrialised world the story is the same – rivers, lakes and coastlines suffer decades of severe pollution, before there is an impetus to clean them up. However, this inaction carries a large cost and can be detrimental to a city's development.
People's health deteriorates when they live near to stinking waterways, full of pathogens and harmful pollutants. Furthermore, sludgy brown rivers with rubbish bobbing along the top deter investors, meaning that valuable business opportunities are lost.
Chinese cities are increasingly aware of these problems and trying hard not to follow in the polluted footsteps of developed cities in the west. "The Chinese like to talk about 'tunnelling through' the environmental Kuznets curve, realising that they will be better off in the medium and long term if they avoid such a trajectory," Vollmer told environmentalresearchweb.
Studying three waterfront developments in Chinese cities, Vollmer has shown that China is indeed managing to tunnel through the curve in some cases, developing in a more sustainable manner but without detriment to economic development.
Suzhou creek is an important navigation channel and flood absorber, passing through Shanghai. Since the 1920s it has been densely populated along its banks and heavily used by industry and for agricultural irrigation. These multiple pressures meant it became one of the most polluted waterways in China.
In 1996 the Shanghai Municipal Government made rehabilitation of Suzhou creek a top priority, with the aim of developing Shanghai into a global city. With assistance from the Asian Development Bank (in the form of loans and technical help) a large improvement has already occurred. Sanitation and wastewater systems have been introduced, land has been reclaimed and made into parks and boulevards and water quality has increased. Economically the rehabilitation is already paying for itself, with an estimated 22% rate of return.
Similar successful improvements have been made along the Qinhuai River, where it flows through the city of Nanjing (270 km northwest of Shanghai), and Wuli Lake, located between Nanjing and Shanghai. The outcomes are discussed in a paper in Environmental Research Letters.
In each case Vollmer believes that the assistance from development banks, NGOs and international sources has been key in the success of the schemes, providing independent impact assessments and carrying out public consultation, ensuring that the regeneration is supported by the local community. "These projects interest stakeholders who may not have the same motivations, but can agree on end goals that would serve their individual interests," he said.
Businesses see commercial opportunities increase, environmental groups see water quality improve and species re-establish, local people gain more green spaces and water-related recreations and real estate developers get high-value development opportunities.
By acting sooner rather than later Vollmer believes that these cities have avoided some of the worst problems seen in the industrialisation of western cities. "Had they followed the expected trajectory, I would imagine that environmental cleanup would have been delayed by 20 years or more," he said.
And it isn't just China that can learn from the mistakes made by developed countries. Vollmer suspects that all developing countries can benefit from rehabilitating their urban waterfronts, with positive outcomes for humans, the economy and the environment.