World's Largest Dam on Brahmaputra Raises Alarms in India: Northeast India at Stake

China’s approval of the construction of the world’s largest dam on the Brahmaputra River in Tibet, close to the Indian border, has sent shockwaves across the region. The hydropower project, with an estimated cost of USD 137 billion, is poised to become the planet’s largest infrastructure undertaking, surpassing even China’s own Three Gorges Dam.

But its scale, ambition, and strategic location have raised alarm bells in India and Bangladesh, both of which rely on the river’s flow for their water supply — and nowhere are the stakes higher than in Northeast India.

The dam is planned to be built in a significant gorge in the Himalayas, where the Brahmaputra makes a U-turn before entering Arunachal Pradesh and flowing into Bangladesh. For Northeast India, the implications of this project are profound. The region, particularly Assam, relies heavily on the Brahmaputra not only for irrigation and drinking water but also as a lifeline for its economy, transportation, and ecology. Any potential alteration in the river’s flow could have devastating effects on the flood-prone region, exacerbating the already volatile situation during monsoons, when water levels in the river are at their peak.

The project, as part of China’s 14th Five-Year Plan (2021-2025), has sparked concerns about China's control over water flow. Critics argue that such a vast undertaking could allow China to manipulate water levels, potentially releasing large quantities of water during periods of geopolitical tension, with disastrous consequences for Northeast India. The region has already faced severe floods in the past, and any drastic changes in the Brahmaputra’s flow could aggravate the damage, displacing thousands and crippling local infrastructure.

India is already building its own dam over the Brahmaputra in Arunachal Pradesh, but with this massive Chinese project, questions arise about the balance of power and potential risks. The two countries have had an ongoing dialogue about sharing hydrological data on the river, but is that enough to address the risks posed by such a high-stakes project? If China controls the upper reaches of the river, it could further deepen the dependency of Northeast India on China’s decisions.

Despite China's assurances that the dam will prioritize ecological protection and mitigate earthquake risks — as the project is located along a tectonic plate boundary — doubts linger. Will the site’s proximity to an active seismic zone be enough to ensure the project’s safety? Or will the region’s frequent earthquakes pose an unforeseen threat to its long-term stability, further complicating the situation for Northeast India?

The dam, expected to generate over 300 billion kWh of electricity annually — enough for over 300 million people — is being heralded as a symbol of China’s energy ambition. But beyond its energy potential, the dam’s impact on the region’s geopolitical landscape is far-reaching. China’s control over the Brahmaputra’s water resources could have significant national security implications, not just for Tibet, but for South Asia as a whole — and particularly for Northeast India, which shares a long border with China.

Adding to the concern is China’s claim that the project will boost the region’s development, with potential benefits in green energy and job creation. But how will these benefits weigh against the risks of environmental damage, regional instability, and the fear of water scarcity for neighbouring countries? For Northeast India, which is already grappling with the effects of climate change and flooding, any changes to the river’s flow could spell disaster for millions of people.

As China moves forward with the construction of this colossal project, the questions remain: Will the Brahmaputra Dam truly usher in a new era of sustainable development and international cooperation, or will it exacerbate tensions and create new challenges for Northeast India and the broader South Asian region? The future of the Brahmaputra, and of the people who depend on it, hangs in the balance.