China Begins Work on World's Largest Dam on Brahmaputra River
China has started building the world's largest hydroelectric dam across the Yarlung Tsangpo River—also called the Brahmaputra downstream—only a few kilometres north of Arunachal Pradesh. The $167.8 billion venture is being built by the state-owned China Yajiang Group. The dam will produce 300 billion kWh of power every year upon completion.
But its timing, size, and location have raised alarm bells in New Delhi. Experts are concerned that China's unilateral management of the river flow will pose disastrous implications for India and Bangladesh. Environmentalists caution that it would turn into a water time bomb in a seismic region.
The Brahmaputra is not merely another river—it is a lifeline water source for millions of people in India's northeast. It spreads enormously after entering the Indian borders because of the shape of the land there. Assam Chief Minister Himanta Biswa Sarma recently pointed out that China supplies only 30–35% of the Brahmaputra's entire volume of water.
But the authority is upstream. With this new dam, China has tremendous leverage over water flow. In monsoon months or at times of diplomatic tensions, it may be able to release or withhold water at will. While Pakistan's threat—"What if China stops the Brahmaputra?"—was dismissed as mere scaremongering, Indian experts assert that the threat cannot be pooh-poohed.
Where the dam is constructed further increases the worry. It is being constructed at the 'Great Bend' of the river, which is seismically active. On January 7, a 7.1 magnitude earthquake killed 126 in Tibet. Aftershocks still rattle the area. Five of the 14 already constructed dams had cracks after the earthquake.
Experts are concerned that any structural collapse would lead to devastating floods and landslides downstream—in Arunachal Pradesh, Assam, and even Bangladesh. The project has been labelled by environmentalists as a "ticking time bomb" set to explode.
India and China have no water-sharing agreement. They have previously suspended only a hydrological data-sharing arrangement. The most recent Memorandum of Understanding lapsed in October 2023. Being non-binding, New Delhi cannot blame Beijing for anything.
India had protested during earlier bilateral talks this year. It sought transparency, sharing data, and environmental impact assessments. China has dismissed such appeals and proceeded. Beijing asserts that the project will not affect downstream nations and maintains it seeks to produce clean energy.
But the dam is more than merely a green power project. As Himalayan glaciers recede as a result of global warming, the dominance of higher river sources becomes strategic. Water, like oil, is becoming a geopolitical tool. The one who owns the source owns the future.
India is now confronted with a serious strategic problem. Without a binding treaty or access to real-time information, it remains vulnerable. The new dam positions northeastern India in a vulnerable situation, environmentally as well as diplomatically. The water can flow from China, but so could the next problem.
