Fishermen on the Tonle Sap Lake of the Mekong River
Basin (IndoChina 2024)
The Mekong River is the pulsing lifeline of Southeast Asia. With almost 1,200 unique fish species — of which 400 are found nowhere else on Earth — its rich biodiversity is rivaled only by the Amazon and the Congo.
As the world’s largest inland fishery, the Mekong accounts for more than 15% of global freshwater catch, supporting over 60 million locals dependent on the fishing industry. The Mekong Delta, known as the “rice bowl of Southeast Asia”, contributes to 15% of global rice exports (Tri 2012). It is a vital agricultural region formed where the river meets the sea, home to nearly 20 million people in the agriculture and aquaculture industry.
Yet, the Mekong River is now clogged by a massive network of dams. Over 600 dams have been built or are being built across the Mekong River and its tributaries. Another 400 are being planned for the next decade, expanding the current network by 60% and pushing the total projected dam count to exceed one thousand (Ang et al. 2023).
Hydropower generation will double
The 3,000-mile Mekong is Southeast Asia’s longest river, flowing through six countries: China, Myanmar, Laos, Thailand, Cambodia, and Vietnam (Hirsch 2016). As these nations are experiencing rapid economic and population growth, dams — a relatively low-cost energy source in this water-rich region — have proliferated across the Mekong River Basin in response to rising energy demands (Hecht et al. 2019; International Renewable Energy Agency 2022). All six countries are competing for their share of the river while racing to dominate the hydropower market.
The total hydropower capacity, or the maximum power that can be generated by the entire dam network, had expanded exponentially from one gigawatt in the 1980s, to 35 gigawatts in the 2010s, and is projected to double to 70 gigawatts in the 2020s and beyond.
China was the first to harness the Mekong’s hydropower potential (Cronin 2009), as evidenced by its substantial expansion in hydropower capacity from the 2000s to the 2010s in the following graph. Having built 11 dams along the upper segment of the mainstream Mekong, China had become the focal point of discussions regarding the Mekong Basin, with many expressing concerns about the impact of upstream dams on reducing the water flow to downstream countries (Eyler 2020). However, the pace of dam construction in China is slowing as development gains momentum downstream.
Laos as the next dam hotspot
With an ambitious goal of becoming the “Battery of Southeast Asia”, Laos has the most planned dams and the highest expected growth in hydropower capacity of nearly 20 gigawatts over the next decade. Laos was the third-largest exporter of electricity globally in 2020, with 90% imported by Thailand, and its exports are projected to more than triple by 2030 (Chowdhury et al. 2020; Economic Complexity 2023).
As shown in the sequence of maps below, Laos’ hydropower capacity is expected to grow significantly in the 2020s and beyond. The volume of a river’s flow increases downstream as more rainfall is progressively captured, and Laos’ strategic location along the lower mainstream Mekong provides key access to the greater flow volumes, which can be harnessed for increased hydropower (Biba 2012).