Explainer: China’s Brahmaputra Mega Dam Called ‘Water Bomb’ By India – Here’s Why It’s Alarming Delhi

China’s ambitious dam plan includes five hydropower stations, with a staggering investment of 1.2 trillion yuan ($167.1 billion), according to Xinhua. (Photo: Reuters via ANI)

China Launches Mega Dam Project: China has officially launched construction of what experts call the world’s largest hydropower project, a colossal dam on the Yarlung Zangbo (Brahmaputra) in southeastern Tibet.

The groundbreaking took place in Nyingchi’s Mainling Gorge, announced by Premier Li Qiang, marking the start of a $167.8 billion venture. Five cascade power stations are planned. Electricity generation is pegged at 300 billion kWh per year, enough for over 300 million people, surpassing even the Three Gorges Dam.

Why India and Bangladesh Are Concerned

The dam site lies near Arunachal Pradesh, where the river enters Indian territory as the Siang, later becoming the Brahmaputra in Assam and flowing into Bangladesh.
Arunachal Chief Minister Pema Khandu has called it a “ticking water bomb”, warning of China’s ability to disrupt river flow or trigger sudden water release, threatening tribal communities and livelihoods in India.

The Ministry of External Affairs (MEA) and other senior officials involved in handling river sharing and water security issues have urged China to ensure the rights of downstream countries are not compromised and to allow transparent water data sharing.

How Much Control Could China Actually Wield?

Assam CM Himanta Biswa Sarma and water experts argue China contributes only 30-35% of Brahmaputra flow, mainly via glacial melt and Tibetan rainfall. Over 65% of the flow is generated within India through monsoon-fed tributaries like Subansiri, Lohit, Manas and others.

Research studies estimate China’s contribution at just 15-20%, weakening fears of major flow control from upstream.

Engineering and Geological Complexity

The dam lies in the Yarlung Tsangpo Grand Canyon, one of the deepest in the world.

Construction will involve 420 km of tunnelling through fragile and earthquake-prone terrain near Namcha Barwa (a mountain peak lying in Tibet in the region of Pemako). Experts warn of risks like landslides and seismic displacement.

In January 2025, a 6.8 magnitude earthquake in Tibet damaged hydropower infrastructure, highlighting seismic hazards near the dam zone.

India’s Plans to Offset Risks

India is actively developing the Siang Upper Multipurpose Project, a 11.2 GW hydropower plan near the LAC, to enhance flood control and energy security.

Union Minister Kiren Rijiju has described it as a strategic necessity, pitching it as both a barrier against flood risk and a defensive buffer in future water disputes.

Broader Environmental and Diplomatic Stakes

Analysts point to ethical and ecological implications, including potential displacement of communities and destruction of sacred ecological sites. Himalaya expert groups note an estimated 1.2 million people could be impacted across multiple Tibetan dams.

Environmentalists and think tanks cite Mekong Basin precedents, where upstream dams by China have triggered droughts and disrupted downstream ecosystems.

India and Bangladesh are watching closely as transboundary water law remains weak, no formal treaty exists with China to regulate flow timing or volume.

So, China’s mega-dam is not merely an energy project. It is a geo-environmental flashpoint. India’s concerns range from water security to climate resilience, tribal impacts and strategic leverage that upstream control might afford Beijing.