Boy with fishing net in Don Sadam

Continued Work Towards the Don Sahong Dam Threatens Havoc for Mekong Fisheries

Ame Trandem
Tuesday, June 25, 2013


The site of where the Don Sahong Dam will be built
The site of where the Don Sahong Dam will be built
International Rivers

Bangkok, Thailand:  Work on the second Mekong mainstream dam, the Don Sahong Dam, is progressing rapidly. The project is located in the Khone Falls area of Southern Laos, less than two kilometers upstream from the Laos-Cambodia border. A site visit by International Rivers last week confirmed that work on the dam’s access roads and bridge is scheduled to begin next year. Numerous activities are underway at the project site even though the Government of Lao PDR has not yet initiated the Mekong River Commission’s (MRC) prior consultation process, as required under the 1995 Mekong Agreement.

“Villagers reported to us that construction on the Don Sahong Dam’s bridge and access roads will begin in 2014,” said Ms. Ame Trandem, International Rivers’ Southeast Asia Program Director.  “It’s clear that the Don Sahong Dam is following the same trajectory that the Xayaburi Dam took, in which secrecy and illicit project implementation topples regional cooperation.  Sadly, what is happening at Khone Falls is emblematic of the failure of the MRC to address the problems related to the Xayaburi Dam.”

International Rivers’ observed that over the past two weeks, the dam’s developer, Malaysia’s Mega First Corporation Bhd, hired local people to place markers all over the Don Sadam Island indicating which land would temporarily and permanently be taken for the construction of the dam’s bridge and access roads.  On June 14th, the Vientiane Times reported that the developer has sought the aid of local authorities and residents to clear blocked channels and remove fish traps in attempts to improve fish passage on nearby channels.  Three channels are known to have been cleared thus far of rocks, river bushes, and fishing equipment.  No compensation or livelihood restoration has been provided to the fishermen who can no longer use their lys and other fish traps, which have provided a significant source of income for local households for generations.

As a project affecting the Mekong mainstream, the Don Sahong Dam is expected to undergo the MRC’s regional decision-making process, in which the governments of Lao PDR, Thailand, Cambodia and Vietnam must seek agreement to build the project.  The first case to undergo this process was the Xayaburi Dam in Northern Laos.  While the Don Sahong has yet to initiate this process, there is significant concern that construction activities and backdoor bilateral deals on the Don Sahong will proceed outside of the MRC process, as was the case of the Xayaburi Dam.  International law and the Mekong Agreement prohibit one government from implementing a project while the other governments are still evaluating the proposal, which is part of the obligation of the countries to negotiate “in good faith.”  With the Xayaburi Dam, the developers began work at the dam site, signed the power purchase agreement with Thailand, and signed financing agreements with Thai banks while discussions at the MRC were still underway.

A fish market at Nakasang, Southern Laos, where the Mekong fishers sell their fish.
A fish market at Nakasang, Southern Laos, where the Mekong fishers sell their fish.
International Rivers

Ms. Trandem said, “The Xayaburi Dam has set a dangerous precedent that undermines future regional cooperation and illustrates the need for urgent reform of the MRC’s prior consultation process before additional projects proceed.” 

While the Don Sahong Dam’s 2012 Environmental Impact Assessment report has yet to be released to the public in accordance with Lao laws, experts have long warned of the project’s expected transboundary environmental and social impacts

“The Don Sahong Dam would be an environmental calamity,” said Ms. Pianporn Deetes, International Rivers’ Thailand Campaign Coordinator.  “The project is aimed at increasing Mega First Corporation’s profits while exacerbating the already known and very serious impacts of the dam on regional fisheries and biodiversity.  If built, the Don Sahong Dam will inevitably and irreversibly block the only channel in the Khone Falls that fish can migrate upstream and downstream during the dry season, leading to predictably serious impacts on fish catches, species and the livelihoods of millions of people in the region.”

The Don Sahong Dam is expected to construct a barrier between two islands on the Mekong mainstream on the Hou Sahong Channel, which is the only channel in the Khone Falls area that allows for year-round fish migration. The dam threatens the migration, feeding and breeding patterns of a diverse number of fish species—including major migrations between Laos and Cambodia—which would seriously impact most of the major fisheries of southern Lao. Additionally, one of the few remaining habitats of the already endangered Irrawaddy dolphins will also come under increased threat.  It’s unclear whether the Don Sahong Dam has been officially approved by the Lao government.

“The Mekong River’s fisheries do not stop at each country’s political boundaries. Projects affecting the river need to be decided on a regional basis,” said Ms. Kumpin Aksorn from the Thai community based organization Hug Namkhong who joined the site visit. “The Don Sahong and other mainstream dams are foolhardy and dangerous, as they threaten to fundamentally change the nature of the river and its resources, which serves as the lifeblood for millions of people in the region.  Before cross-border tensions grow, full public disclosure of the project’s environmental impact assessment is urgently required, as well as meaningful consultations with affected communities and neighboring countries.”

The Mekong River Commission’s Annual Informal Donor Meeting is scheduled for June 27 and 28th in Phnom Penh, where Development Partners review the MRC’s past work.   The Development Partners, including Australia, Finland, Japan, Sweden, and the United States, among others, are expected to make a public statement. 

Media contacts: 
  • Ame Trandem, Southeast Asia Program Director, International Rivers, Telephone:  +66 86 882 2426, Email:
  • Pianporn Deetes, Thailand Campaign Coordinator, International Rivers,  Telephone:  +66 81 422 0111, Email:
  • Kumpin Aksorn, Hug Namkhong, Ubon Ratchathani, Telephone: +66 80 736 9330, Email:  (Thai and Lao languages)
More information: 
  • Boy with fishing net in Don Sadam
    Boy with fishing net in Don Sadam
    International Rivers
    View photos of the Don Sahong site

The proposed Don Sahong Hydropower Project would be located on the Mekong River’s mainstream in the Khone Falls area (also known as Siphandone) of southern Laos, less than two km upstream of the Laos-Cambodia border.  This is an area of the Mekong River that is substantially braided with many channels, rapids and waterfalls.  The Don Sahong Dam would create a barrier across the Hou Sahong Channel that would be around 22 meters high and generate approximately 240 to 260 MW of electricity, mainly for export to Thailand or Cambodia. The project’s main developer is Mega First Corporation Berhad of Malaysia (MFCB). In 2010, the Don Sahong Power Company Limited was created as a subsidiary of MFCB and was registered in the British Virgin Islands. 

Like the Xayaburi Dam and other Mekong mainstream projects, the Don Sahong Dam must first undergo the prior consultation process of the Mekong River Commission before it can go forward. The prior consultation process, under the Procedures for Notification, Prior Consultation and Agreement (PNPCA), requires the Lao government to consult with the governments of Thailand, Cambodia and Vietnam with an aim to reach agreement on whether or not the project should proceed. With the Xayaburi project, the project developers began what it called “preparatory work” while the PNPCA was still underway and argued that the PNPCA only applies to full “construction,” although the Mekong Agreement makes no such distinction. The MRC governments have not reached agreement on this interpretation.   

In March 2006, MFCB signed a Memorandum of Understanding with the Government of Laos to prepare feasibility studies for the project.  The dam’s feasibility study and Environmental Impact Assessment were completed in December 2007 by PEC Konsult Sdn Bhd and Australian Power and Water, Ltd.  Subsequently, in February 2008, a Project Development Agreement was signed that authorized MFCB to enter into advanced negotiations and finalize the project details with the Government of Laos and potential electricity buyers. During this time, AECOM New Zealand Limited (previously Maunsell) was hired to extend and finalize the project’s original feasibility studies to incorporate additional studies.  The project’s new Feasibility Study was finished in November 2009 and MFCB reported that the dam’s final Environmental Impact Assessment report was approved by the Government of Laos in April 2012 and that it was close to signing a power purchasing agreement with the government for a 30-year concession. AECOM is currently serving as the Owner’s Engineer. SMEC New Zealand is providing engineering and advisory tasks aimed at obtaining necessary approvals for the project and its construction tenders.

While the Don Sahong Dam’s final Environmental Impact Assessment has not yet been released to the public, the dam is expected to block the migration of many commercial fish species during the dry season. The loss of fish biomass will impact livelihoods and commercial fisheries in Laos, Cambodia, Thailand, and Vietnam, with repercussions for food security and the region’s economies. In the vicinity of the dam site, many families use a traditional type of wing trap fishing, called Ly, which involves setting traps to catch fish that migrate through the channels. Families can earn around $6,000 per year through Ly fishing, and have passed this traditional knowledge through generations. Villagers reported that this type of fishing has already been made illegal near the dam site on some channels, even though no compensation has been provided for the fishermen’s losses.  According to the MRC’s Strategic Environmental Assessment, Mega First will also need to excavate approximately 1.9 million cubic meters of sediment from the riverbed of the Hou Sahong Channel in order to build the dam and improve available flows into the channel, the equivalent of 95,000 truckloads. The excavation would require the use of dynamite or explosives, which would also have a devastating impact on fish habitats, the river’s morphology and its ecosystem.  Furthermore, the dam risks jeopardizing the last remaining population of Irrawaddy dolphins in Laos, as well as diverting water from the spectacular Khone Phapheng Falls, undermining the area’s increasing popularity as a tourist destination.  The project’s 2009 Feasibility Study states that the project will divert flows during the wet season to the Hou Sahong Channel, which will comprise of about 60% of the total flow delivered to the branches of the Mekong River and 9-10% of the total Mekong flow. As a result, approximately 10-12 million tonnes of sediment per year would be diverted into the dam’s headpond. 

Alterations to channels near the Don Sahong Dam site, in order to improve fish passage, are known to have occurred in at least three locations; including the Hou Xang Pheuak Channel, the Hou Sadam Channel and the channel between the Don Khone Lek and Don Pba Soi islands on the Hou Khone Yooak Channel.