Controversies surrounding the massive Three Gorges Dam - which was once again in the international headlines last week - have stirred up an old debate on the mainland about the pros and cons of building dams.
But environmentalists say Beijing's rare admission that there are downsides to the colossal dam project, viewed by many as the mainland's biggest white elephant, has come a bit too late, with dire predictions about the social and environmental havoc it could cause starting to come true.
A current example is one of the worst droughts seen on the mainland in decades, affecting millions of people in downstream areas along the Yangtze River. It is widely believed that the drought has been aggravated by the dam, which holds back water during the dry season to fill its vast reservoir for power generation.
It has proved to be the Achilles heel of all big dams. Billed as a clean and effective solution to the country's power shortages, the Three Gorges and other mega-dams built on the upper reaches of the Yangtze and its tributaries have done exactly the opposite of what the public were told to expect.
They release flood water during the rainy season because of safety concerns, dealing a heavy blow to their much-touted flood-taming role. And even more embarrassingly, they then have to scramble for limited water resources during prolonged droughts.
Combining all that with deadly landslides, massive silt build-up, devastating environmental impacts and problems associated with huge resettlement schemes leads many geological and environmental experts to believe that the innate risks plaguing big dams are almost impossible to tackle.
Even Beijing has admitted it was warned about many of the grave challenges posed by the building of the Three Gorges Dam long before it was allowed to proceed, despite widespread opposition.
For environmentalists, the government's stark admission is a rare opportunity to inform and enlighten the public about the dark side of dam-building, which remains a taboo for mainland media.
They have urged the central government to learn the lessons from the Three Gorges predicament and reconsider its plan to boost hydropower development in the next decade.
Dam-building ground to a virtual halt from 2004 due to environmental concerns, strong public opposition and, arguably most important of all, intervention by Premier Wen Jiabao . But in March, Beijing set an ambitious goal to boost hydropower capacity on the mainland by 50 per cent to 300,000 megawatts by 2015, making hydro-electricity the central pillar of its bid to increase the share of renewable energy in the mix and reduce its reliance on coal.
While hydropower development has suffered setbacks in many industrial countries over the past few decades, the number of dams, including those under construction, continues to surge on the mainland. China Youth Daily, citing official figures, reported this year that there are now more than 250,000 dams either built or being built on the mainland. By the end of 2008 it had 142 dams taller than 100 metres and 5,191 dams taller than 30 metres.
Powerful energy authorities and power-generation companies - which have vowed to speed up dam construction to make up for losses - say they have a stronger case in the wake of Japan's nuclear crisis that further diminished public confidence in the safety of nuclear power.
But despite recent reassurances from Mu Guangfeng, a senior official with the Ministry of Environmental Protection, that environmental standards for the approval of dam projects will not be lowered, environmentalists say they are still worried.
Ma Jun, a water expert and head of the Institute of Public and Environmental Affairs, said it remains to be seen whether the usually toothless green watchdog will be able to hold off dam projects.
'We've seen many times in past years that big dams halted because of environmental concerns were eventually allowed to proceed,' he said. Ma also said the frontier for harnessing hydropower had been pushed towards mountainous areas in Sichuan, Yunnan and even Tibet, that were prone to earthquakes and other geological hazards.
The central government began to build a cluster of dams on the Yarlung Zangbo River on the Tibetan plateau last year, raising quite a few eyebrows in downstream India, where the river is known as the Brahmaputra.
Su Liu, from Civic Exchange, a Hong Kong-based think tank, also expressed concerns last week that dam-building will not only cause irreversible damage to the environment, but also undermine the government's legitimacy and affect the country's stability.
'The huge ecological and social costs have yet to be fully considered,' she told international investors at a forum by brokerage CLSA in Beijing.
'In the end, the nation will bear the risks and the people will suffer the consequences, while developers and a small number of other stakeholders profit.'
She urged global investors to take into consideration the risks and downsides of dam-building and the obvious impact on international relations before being lured into the seemingly lucrative hydro-electricity market.
'We are not opposed to rational development of hydropower, but we have to be careful when there are no checks and balances in the decision-making process and so many uncertainties behind the often rosy predictions about the dam sector,' she said.