The Mekong River, known as the Lancang in China, is the heart and soul of mainland Southeast Asia. Over 60 million people depend on the river and its tributaries for food, water, transport and many other aspects of their daily lives. Mekong supplies people with about 80% of their protein needs. The Mekong is almost 5,000 kilometers long stretching from the Tibetan plateau, through southern China, and then along the border of Myanmar, Laos Thailand, through Cambodia to Vietnam.
Since the 1960s, several mega-schemes to dam the Lower Mekong River’s mainstream to generate electricity have been proposed. The most recent plan, prepared by the Mekong Secretariat in 1994, was shelved in part due to public outcry over the predicted impacts on the river’s fisheries. In 1995 Vietnam, Cambodia, Laos, and Thailand — the four downstream nations on the river — formed the Mekong River Commission, an intergovernmental body tasked with overseeing sustainable development along the river. China never joined and is building dams without any prior consultation with its neighbors. Since mid-2006, Thai, Malaysian, Vietnamese, Russian and Chinese companies have been preparing detailed studies for a cascade of eleven large hydropower dams on the Mekong River’s mainstream. The projects are located at Pak Beng, Luang Prabang, Sayabouri, Pak Lay, and Sanakham in northern Laos; Pak Chom and Ban Koum on the Thai-Lao border; Lat Sua and Don Sahong in southern Laos; and Stung Treng and Sambor in Cambodia. Most of the power generated would be sent to energy-hungry cities in Thailand and Vietnam.
Landlocked Laos is one of the least developed countries in the region and Lao government have been eager to use one of its few natural resources – an abundance of mountains and surging rivers (Lao river network is contributing 35 percent of the Mekong River’s flow) and to transform the country into “the battery of Southeast Asia” by exporting the power generated by numerous hydroelectric projects to their neighbor countries, especially to Thailand and Vietnam. There are already seven hydroelectric dams in Laos and development plan contains 55 building of new large dams, seven of which are under construction and nearly fifteen more at advanced planning stages.
The massive Nam Theun 2 dam with a capacity of 1088MW is under construction. In March 2006, the the Lao government signed an agreement with Mega First Corporation Malaysia, to do a feasibility study to build a Hou Sahong dam, located in Laos less than 2 kilometers from the Laos-Cambodia border on the Mekong River’s mainstream. The dam would be 32 meters high and generate up to 360 MW, mainly for export to Thailand or Cambodia. A Project Development Agreement was signed in 2008, but as yet no final decision has been made by the Lao government. Project would block the crucial passageway through the Hou Sahong channel, the only major channel of fish migration between Cambodia and Laos, which would put at risk 70% of the fish catch in the Lower Mekong Basin. It will also severely reduce the flow to the Khone Falls, Asia’s largest waterfall.
More than 30 projects are under development or at an advanced stage of planning to meet Vietnam’s growing demand for energy. Since 2003, Electricity of Vietnam company is developing a series of dams in both the Sesan and Srepok basins. To make way for these projects, around 190 000 people will be displaced. In addition to developing its domestic hydropower resources, Vietnam with the support of the Asian Development Bank’s Mekong Power Grid plan is signing contracts to import electricity from Laos and Cambodia.
The Cambodian government is on the threshold of committing to an extensive hydropower program, mostly with the backing of Chinese financiers and construction companies. In 2005, the Cambodian Government started construction of Kamchay Dam, cambodian first large domestic hydropower project. The 112 meter high dam will be built by Sinohydro Corporation (China’s leading dam builder, having built 70% of China’s hydropower capacity). In April 2006, China announced a US$600 million aid package to Cambodia, almost half of which financed the Kamchay Dam. In October 2006, the Cambodian government gave approval to the China Southern Power Grid Company to prepare a feasibility study for the massive 3,300 MW Sambor Dam, located on the Mekong mainstream in Kratie province. If approved, it would have a massive impact on the Mekong River’s fisheries as well as on endangered species such as the Irrawaddy dolphin. Further seven projects have started with feasibility studies, four of them are located close to or within the Central Cardamom Protected Forest in Southwest Cambodia.
The Mekong river sustains the world’s second-largest inland fishery (only the Amazon has greater biodiversity) and is home to 1,200 fish species – approximately 50 of which are caught commercially. According to the Mekong River Commission, approximately 2.6 million tons of wild fish and other aquatic resources are harvested each year, worth at least US$2 billion at first-sale value. Taking into account secondary industries, such as fish processing and marketing, the total economic value for the Mekong’s fisheries is between $5.6 and $9.4 billion per year, contributing significantly to the region’s economy. In Laos, a report for the World Fish Centre in 2007, Eric Baran and Blake Ratner calculated the amount of wild fisheries to 64,600 tonnes — 78% of the country’s total fish production and the direct value to the Laos economy is between $66m and $100m – 6% to 8% of GDP.
Around 70 percent of the Mekong River’s commercial fish catch migrate long distances, which is essential for their life cycle. Building dams on the Mekong River’s mainstream will block these migrations. Experience around the world indicates that these impacts cannot be mitigated. Existing fish passage technologies cannot handle the massive volume of fish migrations – which can reach up to 3 million fish per hour at peak migration times. Building dams would block this migration routes and could cause severe problems with supplying food for rural population of Laos and Cambodia, which depends almost completely on river fisheries nowadays.