NEW DELHI, July 19— China has formally launched construction of the world’s biggest dam over the Brahmaputra river in Tibet, triggering fresh concerns for downstream nations, especially India and Bangladesh.
Chinese Premier Li Qiang announced the commencement of work at a ceremony held on Saturday in Nyingchi city in Tibet Autonomous Region, close to the Indian border in Arunachal Pradesh, Chinese state media reported.
The mega hydropower project, located on the lower reaches of the Brahmaputra, known in China as the Yarlung Zangbo, will be built at Mainling in Nyingchi. The dam is part of the Mainling Hydropower Station, and is being promoted as the largest infrastructure venture in the world.
According to Xinhua news agency, the dam will include five cascade hydropower stations, with an estimated total investment of 1.2 trillion Yuan — roughly $167.8 billion.
The project is expected to generate over 300 billion kilowatt-hours of electricity annually, enough to power the needs of more than 300 million people. While much of the power will be exported to other regions in China, a portion will serve local demand in Tibet, officially referred to by Beijing as Xizang.
Top officials from the National Development and Reform Commission, the Power Construction Corporation of China, and representatives from regional administrations were present at the launch event, alongside local residents.
The scale and location of the dam have alarmed India and Bangladesh, both lower riparian states that rely heavily on the Brahmaputra for agriculture, drinking water, and livelihoods. Experts warn that upstream interventions on transboundary rivers could significantly impact water flow, sediment transport, and ecological balance in the downstream areas.
India has repeatedly expressed concern over China’s dam-building activities on the Brahmaputra, especially in the eastern sector bordering Arunachal Pradesh. New Delhi has called for transparency and data-sharing mechanisms on hydrological flows, amid fears of water diversion and environmental disruptions.
Though China has assured that the project will not harm downstream interests, it has yet to enter any formal water-sharing agreement with India or Bangladesh.
