Impoverished Laos is poised to erect the first dam across the Mekong River's mainstream as it pursues its goal of being Asia's battery despite intense opposition from downstream countries and environmental groups.
In what has become Southeast Asia's biggest environmental battle, opponents say the dam in central Laos would open the door for a building spree of many as 10 others on the Mekong in Laos and Cambodia, degrading its fragile ecology and affecting the livelihoods of millions of residents.
A regional river management forum is expected Thursday to approve, reject or postpone a decision on the $3.5 billion Xayaburi dam during a meeting in Cambodia of four Southeast Asian nations through which the mighty, 3,000-mile-long (4,900-kilometer-long) river flows.
However, there are signs that Laos is prepared to go ahead with the project with or without the Mekong River Commission's approval _ since the decisions are not legally binding _ raising questions about the effectiveness of a 15-year project to jointly manage the river.
Laos says it wants to win its neighbors' approval, but companies have already begun working on an approach road and other dam-related facilities, stating that it will "make sure that this dam will not impact countries in the lower Mekong basin."
The dam decision may be the single biggest challenge the Mekong River Commission has faced.
Meeting in April, representatives of Laos, Cambodia, Vietnam and Thailand agreed to defer decision in face of rare disagreement between Laos and its communist neighbor Vietnam as well as protests by nongovernment groups and villagers living along the river.
Vietnam has urged at least a 10-year moratorium on all mainstream dams on the Mekong.
The Switzerland-based World Wide Fund for Nature said this week that a consulting firm which recommended proceeding with the dam was "playing roulette with the livelihoods of over 60 million people."
But landlocked Laos is banking on hydropower, one of its few major resources, to become what it calls the "battery of Asia" and to lift it from the ranks of the world's poorest nations. Thailand agreed last year to buy 95 percent of the electricity output from the 1260 megawatt dam.
Laos has not announced how much revenue it expects from Xayaburi, but its biggest existing dam, Nam Theun 2, which began operation last year, already is projected to earn up to $2 billion over the next 25 years.
The Finnish consulting firm Poyry, hired by Laos earlier this year, concluded that country had properly addressed concerns about the dam's ecological impacts but that more data was needed on fish migration, restoring livelihoods of river residents and other issues.
The World Wide Fund for Nature blasted Poyry for clearing the project while admitting serious data gaps.
The dam would cut across a stretch of the river flanked by forested hills, cliffs and hamlets where ethnic minority groups reside, forcing the resettlement of up 2,100 villagers and impacting tens of thousands of others.
Environmentalists say such a dam would also disrupt fish migrations, block nutrients for downstream farming and even foul Vietnam's rice bowl by slowing the river's speed and allowing saltwater to creep into the Mekong River Delta.
China has placed three dams across the upper reaches of the Mekong and more are planned, but otherwise the mainstream flows free. These dams continue to anger downstream villagers, who maintain fish stocks have plummeted dramatically and riverside farms have suffered.
But building the first dam blocking the mainstream of the Mekong would have far greater consequences, environmental groups warn.
"The Xayaburi Dam will irreparably damage the world's largest freshwater fishery," Aviva Imhof of the US-based International Rivers said in an interview. "The dam will block fish migrations, cause the extinction of threatened species such as the Mekong Giant Catfish, and threaten the livelihoods of hundreds of thousands of people who depend on fisheries for food and income."
Laos insists the dam won't have any significant impact, describing it as the Mekong's "first environmentally friendly hydroelectric project."
"We will continue to convince Mekong River Commission members before going ahead with construction of the dam," Laos Deputy Energy Minister Viraphon Viravong said in an interview with the semi-official Vientiane Times on Monday.
The commission, set up in 1995, has expressed serious reservations about the Xayaburi project but has no final say despite Thursday's meeting in Siem Reap, Cambodia.
The commission has been criticized for producing little but talk and reports while the Mekong deteriorates. But proponents argue that by bringing the four countries together and trying to build consensus, it has so far put the brakes on mainstream dams.
The commission also is handicapped by the reluctance of Mekong nations China and Myanmar to take part.
Laos has the right to proceed on its own, but the poor country would prefer its neighbors' support, especially that of Vietnam, which is a major trading partner and political patron and which has criticized the plans.
The U.S. government also has weighed in, citing concerns over environmental degradation and challenges to food security. When a decision on the dam was postponed in April, U.S. Secretary of State Hillary Rodham Clinton praised Laos as taking a "forward-leaning position."