Stemming the flow – The Mekong and regional stability

Thirty years ago the Mekong River, Southeast Asia's longest, flowed freely for 4,900 km from its source in Tibet to the coast of Vietnam. The Mekong is the world's 12th longest river and eighth or 10th largest in terms of volume of water discharged, depending on the season, and it passes through or alongside China, Myanmar, Laos, Thailand, Cambodia and Vietnam.

However, since the 1980s the character of the river has been steadily transformed by China's hydroelectric dam-building programme in Yunnan province. Three dams are already in operation, while two more large dams at Xiaowan and Nuozhadu are under construction and due for completion in 2012 and 2017 respectively. Plans exist for at least two further dams at Gongguoqiao and Mengson, meaning that by 2030 there could be a series of seven dams in Yunnan.

These projects will have significant consequences for the populations in Southeast Asia that rely on the river. This, in turn, could heighten regional tension as downstream states protest against China's construction plans.