China Begins Construction of World’s Largest Dam on Yarlung Tsangpo, Raising Concerns in India and Bangladesh

China has started building the world’s largest hydropower dam on the Yarlung Tsangpo River in Tibet’s Nyingchi region, near the Indian border, sparking fears in India and Bangladesh about its impact on downstream water flow, ecology, and regional security. The $167 billion project, known as the Motuo Hydropower Station, was launched on July 19, 2025, with Chinese Premier Li Qiang attending the groundbreaking ceremony. Expected to generate three times the energy of China’s Three Gorges Dam, the project has intensified geopolitical tensions due to its potential to control the Brahmaputra River, a lifeline for millions in India and Bangladesh.

Project Details and Strategic Implications
The dam, located in the Yarlung Tsangpo Grand Canyon—the world’s deepest and longest—will feature five cascading hydropower stations and involve drilling 20km-long tunnels through Namcha Barwa mountain to divert water. The river, known as the Siang and Brahmaputra in India and the Jamuna in Bangladesh, drops dramatically at the “Great Bend,” making it a prime site for power generation. China’s state media claims the dam will support carbon neutrality goals and local prosperity, with electricity primarily transmitted to eastern cities under President Xi Jinping’s “xidiandongsong” (sending western electricity eastwards) policy. However, critics argue it could enable China to manipulate water flow, posing a “water bomb” threat by releasing or withholding water, potentially flooding or starving downstream regions.

Concerns in India and Bangladesh
Arunachal Pradesh Chief Minister Pema Khandu warned that the dam could “dry up” the Siang and Brahmaputra rivers, threatening the livelihoods of tribes like the Adi and causing “existential” harm. He raised fears of a deliberate water release devastating India’s Siang belt, a concern echoed by a 2020 Lowy Institute report stating China’s control over Tibetan rivers gives it a “chokehold” on India’s economy. India’s Ministry of External Affairs urged China to ensure downstream interests are not harmed, noting the absence of a water-sharing treaty. India is planning its own 11,000-megawatt Siang Upper Multipurpose Project to counter potential flooding and regulate water flow, though it faces local protests over displacement and environmental damage. Bangladesh, heavily reliant on the Brahmaputra’s delta for agriculture, sent a letter to Beijing in February 2025 requesting transparency, citing risks of sediment disruption and increased riverbank erosion.

Environmental and Geopolitical Risks
The dam’s location on a tectonic boundary prone to earthquakes, including a 7.1-magnitude quake in January 2025 that damaged regional dams, raises concerns about structural safety and catastrophic flooding. Environmentalists warn that trapping sediment could harm agriculture and ecosystems, threatening Bangladesh’s Sundarbans mangrove forest, a UNESCO World Heritage Site. Activists also criticize the project as exploiting Tibetan land, noting Beijing’s suppression of protests against similar dams. The dam’s proximity to the contested Arunachal Pradesh border, claimed by China as “South Tibet,” adds a strategic dimension, potentially escalating Sino-Indian tensions amid ongoing border disputes.

Developing Story
China insists the dam will have no negative downstream impact, but India and Bangladesh remain skeptical, pushing for transparency and mitigation measures. The project underscores the challenges of managing transboundary rivers without binding agreements. For updates, visit GeoKHub.

Note: Information is based on trusted reports, but technical details and long-term impacts remain uncertain due to limited transparency. Monitor official statements from India, Bangladesh, and China for developments.