IRIN - The proposed Xayabury Dam on the lower Mekong River promises to supply much-needed energy to the region, but at a "devastating" environmental and personal cost to surrounding communities, say activists and environmental experts.
"Millions more people in the region are likely to be adversely [affected] through changes to the river's biodiversity, fisheries and sediment flows," said Ame Trandem with International Rivers, a US-based environmental NGO.
The dam's main developer is Thai construction company Ch Karnchang.
Sixty-five million people depend on the Mekong River - the largest inland fishery in the world - for survival and its biodiversity is second only to the Amazon in South America, according to Jeremy Bird, director of the Laos-based Mekong River Commission (MRC), a regional intergovernmental advisory body on any mainstream development conducted on the river.
More than 200,000 fishermen and farmers - most of the lower riverside community - will suffer displacement and reduced earnings if the Xayabury Dam is built in Laos, states International Rivers.
Based on the 2010 Strategic Environmental Assessment (SEA) commissioned by MRC, "dam construction will result in irreversible environmental impacts", said MRC spokeswoman Tiffany Hacker.
Damage to fisheries "cannot be mitigated by fish passes and reservoirs", said Alan Brooks, director of the Phnom Penh-based NGO, World Fish Center.
The dam is the first of 11 hydropower dams proposed along the lower Mekong River. Though a regional agreement requires prior consultation with MRC before a project can move forward, there is no way to enforce this recommendation.
The Mekong Agreement, which recognizes the shared impacts of river development projects on neighbouring countries, stipulates that Thailand, Cambodia, Laos, and Vietnam must all approve major projects on the lower Mekong River.
The four governments may announce their positions on the dam by as early as March 2011, according to International Rivers.
"What happens with the Xayaburi Dam will essentially set the precedent for whether more mainstream dams are built or not, many of which will [have] devastating impacts on the region's people in terms of lost income, livelihood and food security," said Trandem.