On Christmas Eve 2024, the Chinese government announced that it had approved the world’s largest – and, at $137 billion, most expensive – hydropower project on the Yarlung Tsangpo River in the Eastern Himalaya, near its disputed border with India. The project would generate around 60 gigawatts annually, nearly three times the capacity of the Three Gorges Dam, and help China meet its energy transition goals.
The government did not provide any additional information.
Most international media misinterpreted the announcement, assumed that all hydropower projects were dams, and reported that China was building “the world’s largest dam” (BBC, South China Morning Post, New York Times, Economist) near the disputed border. The Indian media were the most alarmed, using AI-generated images to depict China’s “mega-dam” looming over India.
The threat of the dam has reverberated through the Indian public sphere since. Pema Khandu, the chief minister of Arunachal Pradesh, a border state with territory claimed by China, called the “mega-dam” a “water bomb” and asked for India’s largest dam, which is planned for the same river 90 kilometers below the border, to be fast-tracked on national security grounds.
As expected, the project was covered differently in official and unofficial Chinese-language media. These censored, patriotic media outlets are usually very happy to report any time China is world-leading. Their reports on the hydropower project praised its technological innovation, power generation, and even its immense cost. They berated India’s media and government for its assumption of bad intentions, which they claimed were based on India’s own treatment of downstream Bangladesh.
But they did not claim China was building a “mega-dam” or the “world’s largest dam.”
Instead, they have consistently stated that the hydropower project (not the same thing as a dam) would have two reservoirs – one larger and one smaller, but neither “mega” – located on the Tibetan Plateau, hundreds of kilometers upstream from the border. China’s “advanced hydropower technology” would then be deployed to send the water through tunnels drilled through the eastern Himalaya.
Chinese media has claimed that this innovative project will take advantage of the river’s world-beating altitude drop through the world’s steepest and deepest canyon, the Yarlung Tsangpo Gorge. It will avoid the gorge’s intense rains, heavy sediment flows, and the most geologically unstable parts of this pervasively earthquake-prone region.
Is it possible that international and Indian media have gotten this wrong? If so, why hasn’t the Chinese government taken more significant steps to correct them?
This is not the first time miscommunication and misunderstandings have derailed Brahmaputra hydropolitics. They have stopped discussion about another dam China has built close to the disputed border on another Brahmaputra tributary, which led to a functionally useless memorandum of understanding on water data-sharing.
Part of the reason for this disconnect comes from above the gorge. The Chinese government does not clearly communicate its hydropower plans, or at least it does not do this in a way the international media understands. There are also issues below the gorge. Primarily, discussion in the Indian media flattens the river system and therefore does not reflect its “world-beating” dynamic complexity.
In the interest of the river and the people that live along it, we will outline both here.
Above the Gorge
For decades, Chinese formal and informal social media have been reporting on and exoticizing the lower Yarlung Tsangpo River. Early reports focused on the region’s isolation. Metok County, which sits at the bottom of the Yarlung Tsangpo Gorge on the border, was the last county in China to get a road. The gorge sucks moisture up from the wettest region on Earth, northeast India, creating a “wet tongue” that extends onto the Tibetan Plateau. The region’s multi-ethnic, transboundary Adi (called Luoba in China), Monpa, and Tibetan communities are also regularly photographed in their traditional clothes in tourist brochures.
In the last few decades, the Chinese have also excitedly reported all the scientific discoveries that have made this region “world-beating.” Chinese scientists have discovered that the gorge is Earth’s deepest and longest. Five kilometers deep and 240 kilometers long, it is five times as deep and slightly longer than the Grand Canyon and is often called “the Everest of rivers.” The gorge is also counted as one of Earth’s most biodiverse regions, hosting Bengal tigers at its base, clouded leopards in its mid-altitudes, and snow leopards in its alpine heights.
The gorge’s gross potential energy, the amount of energy that things accrue falling off it, is also world-beating, and this has made the development of its hydropower resources an ongoing discussion in China. Along with debate, it also underpinned an unprecedented investment in the scientific study of the region. Scientists have published nearly 6,000 papers on it during the last decade, six times the amount of all previous studies.
From the government’s point of view, both the pros and cons were high-stakes. Potential geological dangers and biodiversity destruction offset the potential energy rewards. In its 14th Five-Year Plan, released in 2020, the Chinese government finally announced it would develop the hydropower resources and direct the energy it created east to China’s major cities. Last year’s announcement followed this.
Since then, Chinese-language sources have reported and speculated in detail on the river’s development. Much of it has not been officially endorsed, but it has not been taken down by Chinese state censors either.
These reports suggest the first of the project’s two dams will be a flow-regulating large – but not “mega” – dam possibly built near a Tibetan town named Menling, more than 250 kilometers upstream from the disputed border. The second, a smaller 20- to 50-meter-high dam, is being constructed near Pe (Chinese: Pei) at the top of the bend, still 200 kilometers from the border. Reports claim that water from the smaller dam will be diverted into tunnels under the Himalayas and run through 12 turbines before entering a small tailings dam and then re-entering the Yarlung Tsangpo near Metok. It would also integrate solar and wind production. This design would take advantage of both the river’s steep descent, and its course around a horseshoe bend, bringing the lower reach within 40 kilometers of its upper reach.
This design would save the region’s critical infrastructure. Upstream from Menling, a cascade of dams is being constructed. The region’s largest and Tibet’s fastest-growing city, Nyingtri, a gateway to the plateau serviced by a newly built high-speed railway line and freeway, sits between Menling and Pe. Downstream from Pe is the core area of the Yarlung Tsangbo Grand Canyon National Nature Reserve.
Fan Xiao, a senior engineer at the Sichuan Bureau of Geological Exploration, suggests that the tunnels will run beneath the Tamnyenla Pass, with turbines on the Shirang River, just below the fortified ridge that marks the Line of Control between India and China. If correct, this means Indian soldiers will overlook the project from their bunkers. Another possibility is a tunnel that runs beneath the Doshong Pass to the Doshong River, near an existing road tunnel.
Chinese engineers developed the Pe-Metok project technology by experimenting with smaller projects in similar terrains. Jinping I and II serve as potential blueprints. Jinping I is a large dam on the Yalong River, while Jinping II, 7 kilometers downstream, is smaller. Tunnels convey water from Jinping II to a lower-altitude power station. These tunnels proved challenging for engineers, who navigated rock bursts during construction.
Jinping II is one of 38 large dams built in the upper Yangzi basin over the past 20 years. Together, they generate five times as much power as the Three Gorges Dam. An additional 27 dams are under construction. These projects have transformed the upper Yangzi’s ecology and displaced Tibetan and Yi communities but received little international attention.
Chinese engineers have also used the same tunneling technology to build the smaller Polo Dam on the upper reaches of the transboundary Zayul (Lohit) River, 90 kilometers above the China-India border. Curiously, this dam, completed in 2016, has caused no alarm in India despite its location much closer to the border than the Pe dam. Plans to enlarge the Polo Dam have also gone unnoticed.
Below the Gorge
The Indian response to their misreading of the Chinese plans has been to push ahead with their own dam on the river, the 11.2 GW Siang Upper Multipurpose Project (SUMP). SUMP would be India’s biggest power producer, but its position at the base of the gorge means it will require a large reservoir, produce less power, and could potentially be more dangerous.
One of the main reasons it may be more dangerous is the amount of silt it will collect. The gorge produces nearly half the entire Brahmaputra Basin’s sediment. Heavy sediment makes dams less efficient and more dangerous. The Chinese project’s decision to position the Pe-Metok dams above the gorge prevents them from being inundated with this sediment. SUMP’s position at the gorge’s base will exaggerate the sediment threat. Positioning the dam there is a curious choice, as the Arunachal Pradesh government insisted that one of the Chinese dam’s main drawbacks would be its sediment flow retention.
This is not the only time it seems Indian officials and the public sphere have underestimated the gorge. As Nilanjan Ghosh, Jayanta Bandyopadhyay, Sayanangshu Modak have explained, the China-India memorandum of understanding on water data-sharing requires China to provide India with readings from gauge stations in the rain shadow on the Tibetan Plateau, rather than through the gorge, where seven times as much rain and snow falls. Commentators then regularly use these distorted figures to suggest the inflows from the river into India are minimal. Recent studies show that the Yarlung Tsangpo contributes 20 percent of the Brahmaputra’s flow, which is by far the most of any of its tributaries, and this may increase to 30 percent due to climate change.
Cooperating Across the Gorge
The lack of engagement with a detailed analysis of the gorge’s unique attributes is not unique to India. Both governments argue that their dams will make the region safer and extol their green benefits. Climate change threatens the entwined food and water security of the 114 million people living in the Brahmaputra basin in China, India, Bhutan, and further downstream in Bangladesh, but, arguably, so do the dams.
Experts and conservationists have repeatedly expressed deep concerns about dam building in this geologically unstable and biodiverse region. Projects built here are vulnerable to landslides and flash floods, like the one that destroyed the Chungtang Dam in Sikkim, India, in 2023, killing over 100 people. The rivers also flow along tectonic faults. The epicenter of the strongest terrestrial earthquake on record, the 8.7 magnitude Assam-Tibet earthquake (1950), sits between Pe, the SUMP site, and the Polo Dam.
The other major issue that is not regularly discussed in either Chinese or Indian media is that these dams are all being built on minority (or Indigenous) lands. They are dotted with sacred sites and have supported Tibetan, Monpa, and Adi people for millennia. Adi people have been protesting dams on their land for years.
In an ideal world, both nations would co-develop a transboundary network of smaller, pumped-storage hydropower projects that would do less to disrupt these communities, be more sustainable, and be less likely to cause or fall victim to earthquakes.
Such a project would join the long list of the Yarlung Tsangpo Gorge’s “world-beating” attributes.