Open Letter Calling for Plans for Don Sahong Dam to be Abandoned

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Open letter from 28 Non-Governmental Organizations to the Lao PDR Government, the Mekong River Commission and the Governments of Thailand, Cambodia and Vietnam

Plea to abandon plans for the Don Sahong Dam on the mainstream Mekong River in the Khone Falls area

To Whom It May Concern,

We are releasing this open letter to express our deep concerns about the possible development of the Don Sahong dam, planned for the mainstream Mekong River in Khong District, Champasak Province, southern Lao PDR. We urge the government of the Lao PDR to refuse approval for this project. We believe that this project is not in the best interests of Lao PDR and its people, and that it would also have serious negative repercussions for neighbouring countries, including Thailand, Cambodia and Vietnam.

We are concerned that the feasibility study currently under development for this project will fail to adequately consider the extremely negative and widespread impacts that the dam would have on Mekong River fish and fisheries. We are concerned that this project could proceed at the expense of the rich biodiversity of the Mekong River and the livelihoods of Lao and Thai people who depend on fish migrating up the Mekong River from Cambodia and Vietnam each year. We are especially concerned that the dam would block fish migrations between Vietnam, Cambodia, Laos and Thailand, and that ultimately it would undermine fisheries-based livelihoods in all four countries.

The Don Sahong dam would be the first dam ever built on the mainstream Mekong River south of China. Although it would not cross the whole Mekong River, it would block one of the mainstream Mekong River channels in the Khone Falls area-the channel known as Hou Sahong in Laos.

The Don Sahong dam would cause a number of serious negative impacts to local people living on Don Sahong and Don Sadam islands. Villagers who live elsewhere but fish in the area seasonally would also suffer. The dam would negatively impact Khone Falls, the only waterfall on the Lower Mekong River and one of Laos’ most important natural places with the potential for future designation as a World Heritage Site. Additionally, the Don Sahong dam would be located just upriver from where the only year-round population of Irrwaddy dolphins in Laos is found. The dam would likely lead to the extinction of the dolphins along the Lao-Cambodia border and would destroy the local tourism industry that depends on them.

The most serious impact of the dam will be on fish and fisheries, affecting thousands of people living along the Mekong River and its tributaries and streams throughout southern and central Laos as well as in Cambodia, Vietnam and Thailand. The Don Sahong dam would block the only channel in the area that fish migrating up from Cambodia can easily pass, especially in the dry season. If a dam is built across the channel and blocks that migration route, fish may not be able to pass the Khone Falls at all, and would not be able to enter Laos from Cambodia.

We are especially concerned that the Lao government and others will be deceived by claims by the project developers that installing a fish pass on the dam would enable fish migrations. In fact, it would be virtually impossible to build a fish pass that would effectively allow all the various species of fish to migrate past the area at all the seasons when migrations occur. These fish have different habitat and water requirements. Other fish passes that have been built in the region have failed. For example, a fish ladder was added to the Pak Mun dam on the Mun River in Thailand, but it has been shown to be largely ineffective in facilitating fish migrations.

We appeal to the Lao PDR government to abandon plans for the Don Sahong dam and other dams on the Mekong River or in the Khone Falls area in order to protect the Mekong River fish and the local livelihoods that depend on them, and preserve an important natural site in Laos. A decision by the Lao government to dam the Hou Sahong would be a disaster for Laos and Lao people, and for the people of neighbouring countries as well.


1. Living River Siam-SEARIN, Thailand
2. Towards Ecological Recovery and Regional Alliance (TERRA), Thailand
3. Thai Volunteer Service, Thailand
4. Confederation of Consumer Organizations, Thailand
5. Campaign for Popular Media Reform, Thailand
6. Assembly of the Poor, Thailand
7. Village People’s Committee on Mun River Livelihood and Community Recovery, Thailand
8. Sirindhorn Dam Network, Thailand
9. Hua Na Dam Network, Thailand
10. Lam Takong Dam Network, Thailand
11. Pak Mun Dam Network, Thailand
12. Network on the Proposed Pong Khun Phet Dam, Thailand
13. Chiang Kong Conservation Group, Thailand
14. Villager Club for Songkhram River Protection, Thailand
15. Tam Mun Project, Thailand
16. CEPA, Cambodia
17. NGO Forum on Cambodia, Cambodia
18. 3S Rivers Protection Network, Cambodia
19. Rivers Watch East and Southeast Asia (RWESA)
20. Mekong Monitor Tasmania, Australia
21. Proyecto Gato, Belgium
22. Finnish Asiatic Society, Finland
23. Advocacy and Monitoring Network on Sustainable Development (AM-Net), Japan
24. Mekong Watch, Japan
25. Institute of Social Studies, the Netherlands
26. Association for International Water Studies (FIVAS), Norway
27. Water Gems, Scotland
28. International Rivers Network (IRN), USA