Leading US, European and Asian financial institutions attended a conference in Bangkok on September 24 co-convened by the WWF and other development partners to highlight the financial, social and environmental risks and responsibilities of hydropower development on the lower Mekong River.

The meeting will also explore ways to understand and mitigate these risks.

"It is a missed opportunity," said Marc Goichot, sustainable infrastructure senior advisor for WWF Greater Mekong.

"Lower Mekong dam sites were selected in the 1960s and they have not been reviewed for the benefit of today's science and technology."

Currently, there are 11 hydropower dams proposed for the lower Mekong River, which runs through Laos, Cambodia, Thailand and Vietnam.

If just one of these dams is built, it will break the lower Mekong's ecosystem connectivity, which will have a cascade of negative effects.

"Putting a dam on the lower Mekong River will block fish migration to spawning grounds, and collapse fish stocks," said Michael Simon, head of the People’s Infrastructure and Environment Programme of Oxfam Australia.

"Do lenders want to be associated with putting the food security of 60 million people in some of the world's poorest countries at risk?" he added.

Forecasts show the productivity of lower Mekong fisheries, which is valued up to US$7 billion annually, would drop by up to 70 percent because of lower Mekong mainstream dams.

In addition, iconic species such as the Mekong giant catfish and Mekong dolphin would face probable extinction if the proposed dams go ahead.

"Hydropower projects can limit their impact on ecosystem connectivity. For example, a large dam can be built in the floodplain beside a river channel rather than across it, or a hydropower project can have no dam at all," said Goichot.

In southern Laos, such an alternative is being proposed by the Lao Department of Electricity and semi-state owned French company CNR (Compagnie Nationale du Rhone).