Water chokehold: Can China's Brahmaputra card devastate India or fail to make any impact?

 As India reassesses its water diplomacy with Pakistan, China has waded into the fray with a veiled threat. “Don’t do onto others what you don’t want done to you,” warned Victor Zhikai Gao, a senior Chinese policy advisor, hinting at Beijing’s strategic leverage over the Brahmaputra — a river critical to India's water security.

( The Brahmaputra basin is immense, covering 580,000 sq km across China, India, Bhutan and Bangladesh. India alone holds 33.6% of its stretch, and the river sustains millions through agriculture, drinking water, and hydropower.)

The timing of this warning, following India’s suspension of the Indus Water Treaty after the Pahalgam terror attack, underscores growing anxieties about China’s upstream power and its implications for the region’s fragile hydrological balance.

At the centre of this geopolitical undertow is the Brahmaputra River — originating from the Angsi Glacier in Tibet, flowing through India and into Bangladesh. Known as the Yarlung Tsangpo in China and Siang in Arunachal Pradesh, the river carves one of the world’s most spectacular natural bends around Namcha Barwa before descending into India.

What elevates this river from geographical marvel to geopolitical flashpoint is Beijing’s ambition: a $137 billion hydropower mega-project deep in Tibet’s Medog County. With a projected output of 60 GW — triple the capacity of the Three Gorges Dam — this project would become the most powerful hydroelectric facility in history. Its location, just 30 km from India’s border, has set off alarms in New Delhi.

The potential for catastrophe is not abstract. Experts warn that if the dam fails — due to seismic activity, structural flaws, or sabotage — the deluge could devastate Arunachal Pradesh and Assam in minutes. And even in normal operations, China’s control over water flow could wreak havoc downstream. By releasing excess water during the monsoon, Beijing could amplify already severe flooding in India's northeastern states, where 40% of the land is flood-prone.

The Brahmaputra basin is immense, covering 580,000 sq km across China, India, Bhutan and Bangladesh. India alone holds 33.6% of its stretch, and the river sustains millions through agriculture, drinking water, and hydropower. With an average discharge of 700,000 cubic feet per second in India alone, and frequent monsoon-induced floods, the stakes could not be higher.

Unlike the Indus Water Treaty with Pakistan, India has no binding agreement with China over the Brahmaputra. A few data-sharing MoUs exist, but China’s upstream position allows it to act unilaterally. This lack of a formal treaty adds to the unpredictability and fuels fears of water being used as a geopolitical tool. Moreover, the equation also involves Bangladesh, which is now a friend of China. 

However, the India-China dynamic is more layered. Despite ongoing border tensions, especially after the Galwan Valley clash, both nations have continued diplomatic and military-level engagements. Crucially, India is not viewed by Beijing as a terrorism sponsor — a distinction that separates its stance from the one toward Pakistan. This provides New Delhi a wider strategic latitude.

Still, Gao’s comment serves as a cautionary reminder. In the murky game of upstream-downstream politics, water may well become the next frontier in Asia’s great power contest.