The Khone Phapheng Falls, a popular tourist attraction at Siphandone

Don Sahong Dam

The construction of the Don Sahong Dam officially began in January 2016. Located in the Siphandone (Khone Falls) area of southern Laos, less than two kilometers upstream of the Laos-Cambodia border, the dam will block the main channel passable year-round by fish migrating between Cambodia, Laos and Thailand, threatening vital subsistence and commercial fisheries in the Lower Mekong Basin. Construction of the dam has been justified on the basis of mitigation measures that developers claim will allow the movement of migratory fish up and downstream. However, these measures have not been adequately tested and scientists are highly critical about their ability to enable continued fish migration on the scale prior to development of the dam.

At Siphandone, the Mekong River drops some 20 to 30 meters through a maze of narrow channels and rapids that weave amongst the area’s many islands (see map). Siphandone’s unique island-river habitat is considered a globally important area for its enormous biodiversity. The Don Sahong Dam will divert water from the spectacular Khone Phapheng waterfall. The project also jeopardizes the survival of Laos’ last remaining permanent population of endangered Irrawaddy Dolphins, whose habitat is located immediately downstream. Serious concerns have been raised about the impact that explosives and chemicals used in the construction of the dam will have on the future of the dolphin population. By threatening popular tourist attractions, the dam undermines the increasing popularity of the Siphandone area as a tourist destination.

Local people have received misleading and incomplete information about the likely impacts of the dam from the project’s developers, Mega First Corporation Berhad of Malaysia. People downstream in Cambodia have received even less information about the project and are facing considerable uncertainty about their futures. In particular, the livelihoods of fishing communities are at risk, as most have no alternative means of income generation.

The Don Sahong Dam just doesn’t add up. For a project that will generate at most 260 MW of electricity for export to Thailand and Cambodia, the dam threatens vital Mekong River fisheries and the area's biological wealth, and undermines food security and the region’s fishery and tourism-based economy.

International Rivers is working with groups throughout the Mekong region and internationally to protect the Siphandone area from this destructive project. We are calling on Mekong decision-makers to halt the construction of the dam until comprehensive studies have been conducted that detail the full extent of the social and environmental impacts and clearly demonstrate how harm can be mitigated and losses compensated. Throughout the Mekong Basin, International Rivers aims to promote transparency, accountability and meaningful public participation in decision-making for mega-dams, in particular for the vulnerable communities who face the brunt of the impacts.