The Brahmaputra, a lifeline for millions across Tibet, India, and Bangladesh, has become a focal point of geopolitical discussion, particularly concerning China’s upstream activities.
The question often arises: Can China ever truly stop or significantly reduce the flow of this mighty river into India? While China’s hydro-engineering prowess is undeniable, a closer look at the river’s unique hydrology and the complex geopolitical landscape reveals a more nuanced answer.
The Brahmaputra’s Hydrological Reality: A River that “Grows in India”
Often, the narrative focuses on China’s upstream advantage. However, it’s crucial to understand that the Brahmaputra, known as the Yarlung Tsangpo in Tibet, gains the majority of its volume after entering India.
Estimates suggest that only about 30-35% of the river’s total flow at the India-Bangladesh border originates from China, primarily from glacial melt and limited rainfall in the Tibetan Plateau.
The remaining and dominant 65-70% of the Brahmaputra’s flow comes from the massive monsoon rainfall within India, particularly in the states of Arunachal Pradesh and Assam, and from numerous major tributaries like the Subansiri, Lohit, and Manas.
This significant contribution from within Indian territory means that even if China were to construct large dams, the river’s overall volume downstream would still be substantially fed by its Indian catchment area.
For instance, the river’s flow at the India-China border is around 2,000 to 3,000 cubic meters per second (m³/s), but it swells to 15,000 to 20,000 m³/s in the Assam plains during the monsoon season.
This substantial increase highlights the monsoon’s overwhelming influence on the river’s discharge.
China’s Dam Projects and Their Implications
China has indeed embarked on ambitious hydropower projects on the Yarlung Tsangpo, including the proposed “super dam” at the Great Bend. These projects are primarily driven by China’s domestic energy needs.
While China maintains that these are “run-of-the-river” projects designed for hydropower generation with minimal water storage, concerns persist in downstream countries.
The primary worries for India and Bangladesh are not necessarily a complete “choking” of the river, which hydrological data suggests is highly improbable, but rather the potential for:
- Flow manipulation: China could, theoretically, reduce flow during dry seasons or release large volumes during flood seasons, impacting water availability for agriculture and causing artificial floods downstream.
- Sedimentation: Dams can trap sediment, which is vital for the fertility of downstream floodplains, particularly in Assam and Bangladesh.
- Data transparency: A lack of consistent and real-time hydrological data sharing from China creates uncertainty and hinders effective flood management and water resource planning in downstream nations. While MoUs exist for data sharing, their implementation has been inconsistent, particularly during periods of heightened geopolitical tension.
- Seismic risk: The Himalayan region is seismically active. Large dam constructions in such zones raise concerns about potential dam failures in the event of major earthquakes, leading to catastrophic downstream impacts.
The Diplomatic and Legal Landscape
There is currently no comprehensive, legally binding water-sharing treaty between China and India regarding the Brahmaputra.
This contrasts with India’s Indus Waters Treaty with Pakistan. The absence of such a framework leaves room for speculation and distrust.
While India has consistently urged China to ensure that upstream activities do not harm downstream interests, China’s approach often adheres to the “Harmon Doctrine,” which asserts the right of an upstream state to utilize water within its territory.
However, international water law generally emphasizes principles of equitable and reasonable utilization and the obligation to prevent significant harm to other riparian states.
The UN Watercourses Convention of 1997, which India and China are not signatories to, provides a framework for cooperation on transboundary watercourses.
Despite the challenges, both countries have engaged in an Expert Level Mechanism (ELM) for data sharing, albeit with periodic disruptions.
The Way Forward: Resilience and Diplomacy
While the idea of China completely stopping the Brahmaputra’s flow is largely a myth dispelled by the river’s vast internal Indian catchment and monsoon-fed nature, the challenges posed by upstream dam construction are real and require careful management.
India’s strategy involves building its own counter-balancing infrastructure, such as the proposed Siang Upper Multipurpose Project, to mitigate potential impacts and enhance its water security.
Ultimately, addressing the Brahmaputra’s hydro-politics requires a multi-pronged approach. This includes continued diplomatic engagement with China to foster greater transparency and cooperation on data sharing, exploring a more comprehensive framework for transboundary water management, and investing in robust domestic water infrastructure and flood preparedness in India.
The Brahmaputra’s flow is a testament to the immense power of nature, and while human intervention can alter it, its fundamental resilience, especially within India, offers a critical buffer against any complete cessation.