It is sometimes called the “Everest of rivers” for its extreme topography. A section of the Yarlung Tsangpo falls 2,000 meters over a 50 km stretch. But what interests Chinese officials is the river’s hydroelectric potential.
On December 25, Xinhuathe state news agency, reported that China had approved plans to build the world’s largest hydroelectric dam on the lower reaches of the Yarlung Tsangpowhich flows from Tibet to the India and Bangladesh.
According to official estimates, the dam could generate 300 billion kilowatt-hours of electricity per year. This would be enough to meet the needs of more than 300 million people and would more than triple the capacity of the Three Gorges Dam, which is currently the largest in the world.
Government hopes new dam will help China eliminate net greenhouse gas emissions (or to be “carbon neutral”) by 2060. But the project faces many challenges.
According to reports, there will be drill four to six 20 km long tunnels through Namcha Barwa Mountain to divert the flow of the Yarlung Tsangpo.
This is difficult enough, but the dam’s construction site is located on the edge of a tectonic plate, making it prone to earthquakes and landslides.
This engineering task is one of the reasons why the cost of the project is expected to reach 1 trillion yuan ($137 billion), which would make it the most expensive infrastructure project in the world.
To build the Three Gorges Dam, the Chinese government resettled more than 1.3 million people. It is unclear how many could be displaced by the new dam, which will be in Medog county in the Tibet Autonomous Region.. Tibet is no stranger to dams.
Dozens of them have been built, often drawing the ire of local people who believe the government is exploiting the region. In February 2024, Authorities arrested hundreds of people protesting against another dam that threatened to leave towns and monasteries under water.
The Medog project raises similar concerns, as well as fears of damage to local ecosystem. Chinese authorities downplay these fears and say downstream flows will not be substantially affected.
This is unlikely to reassure India and Bangladeshwhere the Yarlung Tsangpo is known as Brahmaputra and on which millions of people depend. The three countries do not have any agreement to share water.
So the dam is likely to raise concerns about China’s ability to control the Brahmaputra, especially in India, one of the world’s most water-scarce countries.
At least one study (by Chinese researchers) suggests that a large dam on the Yarlung Tsangpo could benefit all riparian states – if they cooperate – by allowing flows to increase during the dry season.
But skeptics point out that China has built dams on the Mekong that have damaged the environment and hurt fishermen and farmers downstream. Construction of the new dam will take at least a decade. India and Bangladesh could use that time studying how to adapt.
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