- China has stepped up construction of world's largest hydroelectric dam on Yarlung Tsangpo in Tibet near India
- India monitors the project closely due to concerns over downstream impacts on the Brahmaputra river system
- Experts warn damming may alter water flow, sediment transport, ecology, and flood patterns downstream
China has begun construction work on the world's largest hydroelectric dam in the lower parts of the Yarlung Tsangpo River in Tibet, about 50 kilometres from the border with India, posing new worries in New Delhi over the consequences of the massive project.
Intelligence inputs reviewed by Indian agencies, coupled with satellite imaging, suggest that construction work has picked up pace in recent months despite India's long-standing concerns about the downstream impact of such massive damming projects on transboundary rivers.
Yarlung Tsangpo originates in Tibet and flows into India through Arunachal Pradesh, where it becomes the Siang River. It then flows into Assam as the Brahmaputra, a vital water system for millions of Indians in the country.
Officials aware of the matter have told NDTV that the project is being closely monitored by the Indian government, which considers the construction work one of the crucial elements of Beijing's hydropower projects in Tibet.
But the development comes at a time when Indian officials continue to express concern over the downstream impact of such projects, with experts warning that massive damming operations on the river can lead to changes in the natural flow of the water, sediment transport processes, ecological damage, and altered flood patterns downstream.
Besides the downstream impact of the damming operation, the strategic aspect cannot be overlooked, with experts saying that huge dams in the upper reaches of the river would give China additional leverage in case of any dispute by helping Beijing control water flow in the region.
Beijing maintains that its hydropower projects are aimed at generating electricity and would pose no harm to downstream countries like India. But New Delhi is not taking any chances.
In response to queries in Parliament last year, Minister of State for External Affairs Kirti Vardhan Singh said the Centre has taken note of reports regarding the start of construction on the mega-dam.
Singh said that the government had been keeping track of the proposed mega-dam for decades.
"The project was first made public as far back as 1986, and ever since, preparations have been going on in China," he said.
He also said that the government "carefully monitors all developments relating to the Brahmaputra river, including plans by China to develop hydropower projects and takes "necessary measures to protect our interests, including preventive and corrective measures to safeguard life and livelihood of Indian citizens residing in downstream areas".
He said India has time and again expressed its concerns to the Chinese side through official channels and that all issues regarding transboundary rivers are discussed through the Expert Level Mechanism established in 2006.
"Government has consistently conveyed its views and concerns to the Chinese authorities, and has urged them to ensure that the interests of downstream states are not harmed by any activities in upstream areas," Singh said.
The issue was also raised at the highest levels during the visit of External Affairs Minister S Jaishankar to China for the Shanghai Cooperation Organisation Foreign Ministers' Meeting in July 2025, officials told NDTV.
Besides diplomatic engagement, India is also focusing on enhancing its capabilities and taking preparatory measures against any disaster downstream.
