A ‘water bomb' in Northeast India: China's mega dam project in Tibet could deepen South Asia's water crisis

Indian Express

5 days ago

On July 19, Chinese Premier Li Qiang announced the construction of the Yarlung Tsangpo Hydropower Project in Medog County, Tibet. This $167 billion mega-dam would be the world's largest dam, capable of generating 60 gigawatts of capacity and 300 billion kilowatt-hours of annual output, which is three times the size of the Three Gorges Dam on the Yangtze River. This project is situated at the 'Great Bend' of the Yarlung Tsangpo River, also known as the Brahmaputra in India and the Jamuna in Bangladesh. China touts it as its push to become carbon neutral by 2060, though downstream nations, notably India and Bangladesh, are nervously preparing for drastic environmental, economic and geopolitical fallout.
China has framed the dam as a renewable energy bonanza as much as an economic engine for Tibet. By harnessing the river's 2,000-meter elevation drop over a 50-kilometre stretch in the Yarlung Tsangpo Grand Canyon — the world's deepest — the project will provide 300 million people with clean power, reduce reliance on coal and stimulate regional economic development through infrastructure and employment. Beijing maintains that there will be 'no negative impact' downstream, arguing that the hydro project will help with flood control and comply with laws protecting the ecologically fragile Qinghai-Tibet Plateau. According to the Chinese foreign ministry, they have promised dialogue on disaster prevention, highlighting responsible management of transboundary rivers, and declaiming that 65-70 per cent of the Brahmaputra's flow is the result of monsoon rain in India, not the melt of Tibetan glaciers.
India, however, regards the dam as both a strategic and environmental menace. The Yarlung Tsangpo contributes one-third of the flow to the Brahmaputra, which supports 130 million people in Assam and Arunachal Pradesh, for agriculture, fisheries and drinking water. Indian officials, including Arunachal Pradesh MP Tapir Gao, have described it as a potential 'water bomb', fearing that China could regulate flows to induce floods, as it did in the devastating 2000 Siang River disaster that washed away bridges, or to worsen droughts in dry seasons. India's Ministry of External Affairs has called on Beijing to take into account downstream interests, and New Delhi is planning an 11.2-gigawatt dam on the Siang River to assert its water rights. The lack of a water-sharing treaty between China, India, and Bangladesh further exacerbates the situation, particularly after the Doklam Standoff in 2017, when China stopped sharing data with India, while they continued sharing it with Bangladesh. Similarly, since 2023, data sharing (MoUs) have also expired, but no such step has been taken on it.
Bangladesh faces even graver risks, with the Brahmaputra (Jamuna) supporting 55 per cent of its irrigation needs. The reduced flows could also increase coastal salinity intrusion, exacerbating water stress amid rising sea levels due to climate change. The dam's potential to disrupt sediment transport, vital for the Ganges-Brahmaputra Delta, threatens especially 218 fish species, including economically important ones like Hilsa and Mahseer that sustain two million livelihoods.
The environmental concerns intensify these tensions further. The dam's location in a seismically active, landslide-prone region risks catastrophic failure, as evidenced by 2018 landslides that temporarily blocked the river. It threatens to flood Tibetan valleys, displace local communities, and submerge sacred sites, prompting protests akin to those against the Kamtok Dam, which faced heavy crackdowns. Similarly, after the announcement of the Medog county dam in December 2024, there was a huge earthquake in Tibet with a Richter scale 7.5 magnitude, which shows how vulnerable it is.
To mitigate such transboundary disputes, a middle riparian country comprising India could amplify downstream voices. This coalition would advocate for equitable water management, pressing for legally binding agreements under frameworks like the UN Water Convention of 1997. By uniting, these nations could demand consistent hydrological data-sharing, joint environmental assessments, and early warning systems for floods.
Further, the proposed South Asia Water NATO could provide a robust regional framework to address these challenges. This multilateral alliance, encompassing riparian states of the Brahmaputra, Indus, and Ganges, would institutionalise cooperation on water security. Modelled on collective security principles, it would enforce protocols for data transparency, dispute resolution, and disaster preparedness. By mandating environmental impact assessments and equitable water-sharing, Water NATO could prevent unilateral actions from destabilising the region. Also, the lessons from the Nile Basin Initiative (NBI) and the Mekong River Commission (MRC) can play a vital role in understanding the mechanisms to work on.
The Yarlung Tsangpo hydropower project highlights the urgent need for cooperative water governance. While China pursues its clean energy ambitions, the risks of ecological devastation, economic disruption, and geopolitical escalation demand immediate action. A middle riparian group and a South Asia Water NATO could ensure transparency, equity, and resilience, safeguarding millions of lives downstream. Without such mechanisms, this 'project of the century' risks igniting a regional crisis, threatening the delicate balance of South Asia's water-dependent ecosystems and economies.
The writer is special advisor for South Asia at the Parley Policy Initiative, Republic of Korea