Confluence of the Sekong and Sekaman Rivers

Sekong River Basin

The vast Sekong River Basin is one of the most important Mekong tributaries. Originating in the Central Highlands of Vietnam, the Sekong River flows through Laos and then enters Cambodia to join the mighty Mekong River. Contributing ten percent of the water flow to the Mekong River, the Sekong River joins with the Sesan and Srepok Rivers to form the 3S River Basin, a major sub-basin of the Mekong River system.

In Laos, the waters of the Sekong and its many smaller tributary rivers are home to tens of thousands of people from at least 20 different ethnic groups, all of whom rely on the surrounding forests, the fish and fertile lands for gathering and cultivating food. In addition, in the Stung Treng province of Cambodia, there are 30,000 people living along the Sekong River, the majority of whom also belong to ethnic minority groups, relying on the land and watershed for subsistence.

This river basin supports a wide diversity of mammal, reptile and bird species of global significance, including the Asian elephant, tigers, gibbons, Asiatic Black and Sun Bears, Siamese crocodile, king cobra, cranes, ibis and endangered hornbills. The river is renowned for a profound diversity of fish species, with over 300-350 species estimated to be present throughout the Sekong River Basin.

Yet, the health of local communities and that of the surrounding riparian ecosystems are being threatened by aggressive natural resource developments. Up to 17 dams are planned in the basin to export electricity to Vietnam and Thailand, three of which (Xekaman 1, Xekaman 3 and Xe Namnoy 1) are already under construction. To date, the only large dam in full operation within the Sekong River Basin in Laos is the Houay Ho Dam, completed at the end of 1998. It has proven to be disastrous for the ethnic minority villagers who were resettled, has caused significant suffering to downstream communities, and has been cloaked in shady deals that have left Laos without dividends until nearly the end of the 30-year concession period.

Now, eight dams are moving forward as part of the Lao-Vietnam transmission line project, which is considered as a critical component of the Greater Mekong Subregion (GMS) Power Plan. Some of the main proponents of the dams in the Sekong Basin include Vietnam’s Song Da Corporation and Viet-Lao Power Company, Korea’s SK Engineering and Construction and Korea Western Power Company, as well as Thailand’s Ratchaburi Electric Generating Holding Company.

The dams planned on the Sekong River, specifically Sekong 3A and 3B as well as Sekong 4, are predicted to lead to a sharp decline in fisheries, significantly affecting local livelihoods. Nevertheless, alarmingly little information exists about the likely long-term transboundary and cumulative impacts of any of these dams on the communities living along the Sekong and its tributaries, including in Cambodia.  International Rivers is monitoring dam construction and the situation of local affected communities, while calling on financiers of the projects, including the Asian Development Bank, to make sure that projects comply with both Lao law and ADB safeguard policy requirements.

* Note: Sekong is also spelled Xekong or Xe Kong; Sekaman is also spelled Xekaman or Xe Kaman.