China is poised to weaponize one of the world’s most essential natural resources: water. With plans underway to construct the world’s largest hydropower project—a colossal 60,000 MW mega-dam on the Yarlung Tsangpo River, which is known as the Brahmaputra in India—Beijing’s actions are causing serious concern in New Delhi. This project is not only an engineering marvel but also a potential geopolitical weapon, offering China unprecedented control over one of Asia’s most significant transnational rivers.
The Yarlung Tsangpo, originating in the Qinghai-Tibet Plateau in China, flows for nearly 2,900 kilometers, carving its way through the Tibetan Autonomous Region, across the Himalayas, and into India. Upon entering Indian territory, it transforms into the Brahmaputra, one of the mightiest rivers of South Asia. It continues to flow through Assam and Arunachal Pradesh, eventually merging with the Ganges and emptying into the Bay of Bengal via Bangladesh.
This river system is not only vital for India but for an estimated 1.8 billion people in countries like China, Bhutan, Bangladesh, and India. It provides drinking water, irrigation for vast agricultural lands, and hydroelectric power, making it a lifeline for millions of people. Control over this river, therefore, carries enormous stakes.
China’s latest move—constructing the world’s largest hydropower plant on the Yarlung Tsangpo at the “Great Bend” in Tibet—is more than just a domestic energy project. The location is significant: the Great Bend is a remote and dramatic U-turn of the river near the disputed border between China and India’s northeastern state of Arunachal Pradesh. Here, the river’s elevation drops sharply by over 2,700 meters within a 50-kilometer stretch, creating ideal conditions for hydropower generation.
While Beijing claims that the dam is intended to address domestic issues like energy shortages and water scarcity, experts argue that the project is just as much about strategic geopolitical dominance. India is increasingly concerned that by controlling the upper reaches of the Brahmaputra, China could manipulate the river’s flow, which would have significant repercussions for downstream nations.
Neeraj Singh Manhas, a Special Advisor for the South Parley Policy Initiative in the Republic of Korea, points out that “for China, controlling the headwaters of major rivers provides an upper hand in negotiating with downstream nations.” This gives Beijing the ability to potentially withhold water during dry seasons or release excessive amounts during the monsoon, which could cause floods in Indian states like Assam and Arunachal Pradesh.
India’s concerns about China weaponizing water are not unfounded. The construction of the Motuo mega-dam comes amid heightened tensions between the two countries, particularly after the Galwan Valley clashes in 2020. The dispute between India and China, centered on their contested border in the Himalayas, has already seen its fair share of conflict, but the construction of this massive dam adds another layer to their strategic rivalry.
In recent years, China has already demonstrated its willingness to use water as a geopolitical lever. In 2021, Beijing cut the flow of the Mekong River—another major transboundary waterway—for three weeks, affecting millions of people in downstream countries like Cambodia, Laos, Thailand, and Vietnam. The cut was ostensibly for power-line maintenance, but it led to severe drought conditions, crop failures, and economic losses.
A similar scenario is now playing out with the Brahmaputra. India fears that during the lean season, China could curtail the river’s flow, exacerbating water shortages in northeastern India. Conversely, during the monsoon season, China could release excessive water, triggering catastrophic floods in downstream areas like Arunachal Pradesh and Assam.
In response to China’s growing control over the Yarlung Tsangpo, India is now pursuing its own hydropower project on the Siang River, a tributary of the Brahmaputra in the northeastern state of Arunachal Pradesh. The proposed 11,000 MW Upper Siang hydropower project, which will be built by the National Hydroelectric Power Corporation (NHPC), aims to assert India’s riparian rights and reduce dependence on China’s actions upstream.
The project, first proposed in 2017 by India’s central government think tank Niti Ayog, is envisioned as the country’s largest hydropower project. It would include a buffer storage of over 9 billion cubic meters of water during peak monsoons, which could help regulate water flow during lean seasons or provide a safety buffer in case of unexpected water releases from China’s dams.
The NHPC has identified three possible sites along the Siang—Uggeng, Ditte Dimme, and Parong—for the project and is currently conducting pre-feasibility studies to determine the best location. These studies will assess the cost of the dam, its potential impact on local communities, and whether the rock formations in the area are strong enough to support such a large structure.
However, the project has already encountered significant opposition from local communities in Arunachal Pradesh, who fear that the dam could disrupt their way of life, damage the local ecology, and lead to forced relocations. Additionally, building a dam of this magnitude in a region prone to seismic activity poses risks.
India is not the only country worried about China’s growing control over the Brahmaputra. Bangladesh, which lies downstream and relies on the river for agriculture and drinking water, also stands to be severely affected. Any significant alteration in the Brahmaputra’s flow could lead to devastating floods or droughts in the country, where millions of people live in the river basin.
The situation mirrors the impact China’s upstream Mekong River dams have had on Southeast Asian countries. Since 2019, Thailand, Cambodia, and Vietnam have experienced unprecedented droughts, severely impacting their economies and food security. Reservoirs have dried up, fish populations have plummeted, and farmers have struggled to produce crops.
Bhutan, a country with a small but strategic role in the region’s water politics, also faces potential challenges. While Bhutan is not directly impacted by the Brahmaputra, it relies on water-sharing agreements with India. Any alteration in the river’s flow could affect Bhutan’s own hydropower projects, many of which are built in collaboration with India.
The concept of water being used as a weapon is not new. Historically, control over water resources has often been a source of conflict. However, as climate change exacerbates water scarcity and populations continue to grow, water security has become an increasingly urgent issue in many parts of the world.
China’s control over the Yarlung Tsangpo is part of a broader trend of using transboundary water resources for geopolitical leverage. As Manhas and Dr. Rahul M. Lad argued in a research paper, “this trend signifies the potential ‘weaponization’ of transboundary water resources, posing a significant threat to regional stability in South Asia.”
Following the Doklam standoff between India and China in 2017, China abruptly stopped sharing hydrological data for the Brahmaputra River with India, despite prior agreements between the two countries. While Bangladesh continued to receive hydrological data from China without interruption, India was left in the dark. This selective sharing of information underscores China’s intent to use water resources as a political tool to pressure India within the broader South Asian context.
The Brahmaputra is one of the world’s most significant transnational river systems, and any disruption in its flow could have catastrophic consequences for millions of people in China, India, Bhutan, and Bangladesh. As tensions rise between India and China, particularly in a post-Galwan world, the weaponization of water has become a critical issue in their bilateral relations.
For India, the construction of the Motuo mega-dam is not just a technical concern but a direct challenge to its sovereignty and water security. In response, India’s decision to build the Upper Siang hydropower project is a strategic move to assert its rights as a riparian state. However, the construction of competing dams risks escalating tensions further.
The situation calls for urgent diplomatic intervention. Water-sharing agreements, open communication, and cooperation on environmental issues are essential to preventing the weaponization of water from destabilizing the region. As climate change continues to strain global water resources, the need for sustainable management of transboundary rivers like the Brahmaputra has never been more urgent.
