India holds the water advantage despite China’s Brahmaputra dam push

New Delhi/Beijing: As China pushes ahead with its ambitious plan to build a $16.7 billion mega-dam on the Yarlung Tsangpo – known as the Brahmaputra in India – concerns have inevitably surged about the possible downstream impact on India and Bangladesh.

The proposed Medog Hydropower Project, reportedly with a capacity of 70 GW (more than triple the output of the Three Gorges Dam), has sparked fears of water weaponisation and hydrological coercion. However, a closer analysis of geography, hydrology, and dam design offers compelling reasons why India’s leverage remains intact – and its water security largely unthreatened.

The Brahmaputra River originates in the glacial regions of western Tibet as the Yarlung Tsangpo and flows eastward before making a dramatic U-turn at the ‘Great Bend’ near Medog (Motuo), Tibet.

From there, it enters Arunachal Pradesh as the Siang, gains volume and force as it flows through Assam (where it becomes the Brahmaputra), and eventually moves into Bangladesh as the Jamuna.

Although about two-thirds of the river basin lies in Chinese-controlled Tibet, over 80% of the Brahmaputra’s actual water volume is generated in India. This seeming paradox is easily explained by rainfall patterns.

Tibet receives a sparse annual rainfall of just 300 mm, while Northeast India is drenched by over 2,300 mm of rain annually, with some areas receiving even more. Moreover, numerous Indian tributaries and snow-fed rivers significantly augment the Brahmaputra’s flow, making India – not China – the primary contributor to the river’s volume.

Much of the alarm over Chinese hydropower projects stems from fears of upstream water manipulation. However, most of China’s existing and proposed dams on the Yarlung Tsangpo, including the massive Medog project, are understood to be run-of-the-river projects. These types of dams generate electricity by using the river’s natural flow, without the need for large reservoirs or long-term water storage.

This technical detail matters: run-of-the-river dams cannot significantly alter downstream flows over extended periods, say experts. They might momentarily shift or slow water release during electricity generation cycles, but they lack the capacity to withhold water seasonally or weaponise it as a sustained geopolitical tool, experts add. In essence, China’s current dam-building trajectory offers limited scope for using the Brahmaputra as leverage against India.

Interestingly, Assam Chief Minister Himanta Biswa Sarma has taken a contrarian view, dismissing fears as part of a “scare narrative” reminiscent of Pakistan’s tactics. He argues that even if China were to reduce the Brahmaputra’s flow marginally, it could help mitigate Assam’s annual flood devastation, which causes immense loss of life and property every monsoon.

Given that much of the river’s destructive flooding is driven by torrential local rainfall and the swelling of Indian tributaries, a slight upstream regulation may, in fact, help stabilise seasonal fluctuations. This aligns with India’s own plans to build storage and flood-control infrastructure to manage excess water more effectively, argue experts.

While vigilance is certainly warranted – especially around data transparency and ecological impact – India’s strategic position remains resilient, according to the experts. The reality is that China cannot easily control a river whose volume is dominantly shaped within Indian territory.

The combination of monsoonal rains, numerous tributaries, and India’s topographical dominance in the lower basin ensures that Chinese influence on the Brahmaputra’s flow is inherently limited.

Moreover, international norms and regional geopolitics would make overt manipulation risky and diplomatically costly for China, especially given Bangladesh’s and India’s collective interests in the river’s health and flow, say diplomatic experts.

–IANS