New Delhi: China’s construction of a massive hydropower project on the Yarlung Zangbo River in Tibet has sparked growing concerns in India and other South Asian countries over the possibility of severe water shortages and environmental risks downstream.
The project, announced earlier this year, is set to become the world’s largest hydropower undertaking. Built in Medog County of Tibet, the mega-dam will involve a cascade of five dams with an investment estimated at nearly 170 billion US dollars. Once completed, it is expected to generate almost three times the annual power output of China’s Three Gorges Dam, making it a landmark engineering venture.
While Beijing has promoted the project as a clean energy initiative crucial for its future power security, India and Bangladesh fear it could alter the flow of the Brahmaputra River, which is known as the Yarlung Zangbo in Tibet. Indian experts warn that water flows could decline by up to 85 percent during the dry season, jeopardizing the livelihoods of millions of people across Assam and the downstream delta regions of Bangladesh.
Environmentalists also caution that the project sits in one of the world’s most ecologically fragile and earthquake-prone zones. Scientists fear potential geological disasters such as landslides and earthquakes, as well as irreversible damage to biodiversity in the region. Critics argue that disruptions to sediment flow could undermine agricultural productivity and fisheries that sustain large populations in South Asia.
India has responded by accelerating plans for its own Upper Siang Multipurpose Storage Dam in Arunachal Pradesh. The dam, with a storage capacity of about 14 billion cubic meters, is aimed at safeguarding India’s water reserves and countering China’s control over the river. However, the project has drawn local opposition, particularly among tribal communities, due to fears of displacement and the submergence of villages.
Bangladesh, though less vocal than India, is also watching the developments closely, given its heavy dependence on the Brahmaputra for irrigation and flood management.
Chinese authorities, on the other hand, argue that upstream dams have historically increased dry-season flows, citing studies claiming benefits for water management. Still, Indian officials remain skeptical, with some political leaders warning that the dam could act as a “water bomb,” giving China the ability to manipulate water supplies during times of conflict.
The issue is further complicated by the absence of a binding transboundary water-sharing agreement between China, India, and Bangladesh. Without such a framework, trust between the countries remains fragile, and experts warn that the region could be heading toward a hydro-political standoff.
China expects the project to become operational in the 2030s, anchoring its role as a cornerstone of the country’s renewable energy ambitions. Meanwhile, India is expected to continue building its own counter-projects and pushing for stronger diplomatic mechanisms to prevent a potential water crisis.
The mega-dam highlights the growing intersection of energy security, environmental sustainability, and geopolitical rivalry in Asia. As construction progresses, the Brahmaputra basin may emerge as a critical flashpoint in regional relations unless cooperative solutions are found.