Letter From The Mekong: Examining Hydropower Dams

NOTE: Stimson Senior Associate Rich Cronin and Research Associate Zach Dubel recently returned from a trip to Laos and Thailand to examine the status and future of hydropower dams on the Lower Mekong Basin, along with the impact of the dams on regional relations.

The government of Laos took many observers by surprise when it abruptly announced its decision in November 2012 to go ahead with the highly controversial Xayaburi dam project on the Mekong mainstream in northern Laos. The Lao government had agreed the previous year to suspend for an indefinite period the construction by the Thai developer of the 32 meter high dam to allow further study of its impact on the river.

The project has been strongly opposed by the governments of Vietnam and Cambodia, along with a wide range of regional civil society activists and international organizations. Project opponents are concerned about the serious negative local and transboundary impacts of mainstream dams on the environment, human security and regional relations. 

In late January my colleague Zach Dubel and I took a scenic eight-hour, 100-mile (150 km) boat trip upriver from Luang Prabang to Pak Beng, a small town near the next planned Lao mainstream dam.  

China’s construction of a massive cascade of seven or eight large- to mega-sized dams in China’s Yunnan Province and plans for up to 12 dams on the Lao, Lao-Thai and Cambodian stretches of the Mekong will change the river from wild and free-flowing into a series of slow moving lakes reaching far upstream.   The anticipation of such dramatic changes has created a “see it before it’s gone” situation.

Because of the 30-foot or more seasonal difference in the height of the river in northern Laos between the wettest and driest months, the iconic long shovel-like bows of these traditional Lao craft  (see photo) with their steel hulls and wooden superstructures are ideally suited for beaching, regardless of water level.  

The construction of some mainstream dams (starting with Xayaburi) seems inevitable because of the strong desire of the Lao government to develop the country’s large hydroelectric power potential for export earnings, the influence of foreign developers who offer relatively “cost-free” build-own-operate and transfer projects, significant demand from Thailand’s state-owned electric generating authority, and ample investment capital.

In the worst-case scenario, the Lao government will decide not to invoke the Mekong River Commission’s procedures for a six-month period for notification, prior consultation and agreement, or it will allow the six-month process but ignore the findings and recommendations of the accompanying Mekong River Commission’s expert prior consultation review report.   

Cambodia will also view Laos’ decision as sharply reducing the environmental and socioeconomic value of its stretches of the Mekong, in particular the rich fisheries of the Tonle Sap.  This worst-case scenario has the potential to create domestic instability and fissures in regional relations, and undermine the Mekong River Commission’s goal of cooperative, science-based decision-making. 

Current plans for mainstream dams involve a half-dozen different foreign developers, including Thai (3 companies), Chinese (3 companies), Vietnamese and Malaysian. The resultant dam construction will be uncoordinated and chaotic.  Because neither Laos nor Cambodia has the human or institutional capacity to carry out the necessary planning, coordination and oversight capacity, the result will likely be even more damage to the river’s natural hydrology and ecology than is necessary.

The most optimistic scenario would involve significantly fewer than the nine planned or proposed mainstream dams in Laos. Any dams Laos decided to build would be confined to northern Laos, above the capital of Vientiane. The six Lao and Lao-Thai dams planned for southern Laos and two for Cambodia, all of which would be more damaging to wild fisheries by several orders of magnitude, would be dropped or deferred indefinitely.  

Mekong Standard

The best realistic outcome would involve a commitment by all four Lower Mekong Basin countries to share the risks and benefits of additional mainstream hydropower development within the framework of a stronger and more effective Mekong River Commission, along with an agreed Mekong Standard for a maximum acceptable level of risk.   It would involve the agreement of all Mekong River Commission countries on a maximum limit on adverse transboundary impacts on fisheries, livelihoods, water quality and silt flows. 

Linking the Mekong Standard to proposals for strengthening of the six-month period for notification, prior consultation and agreement process would underscore continuity with a 1995 agreement, which already provides that the impact of infrastructure projects should not cause changes that exceed certain minimum and maximum seasonal flows in and out of the Tonle Sap.  Enhanced standards would not guarantee the best decisions, but a reasonable understanding of the transboundary distribution of costs and benefits is essential to the continued viability of the river’s core ecosystems and the Mekong Delta. 

This best-case scenario would not be “sustainable” in the classic environmental sense, but would feature defensible tradeoffs based on risks that would be calculated on a full-scope analysis of the costs and benefits.


Photo by Richard Cronin

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