Geography: June 2025 UPSC Current Affairs | Geography for UPSC CSE PDF Download

Brahmaputra Flow in India and Impact of Chinese Dams

In Context

• India is keeping a close watch on Chinese infrastructure projects along the Brahmaputra River, especially hydropower initiatives. This is due to their potential impact on downstream areas in India, such as Arunachal Pradesh and Assam.

Brahmaputra River System

• The Brahmaputra River starts in the Kailash ranges at an elevation of 5,150 meters and flows a total of 2,900 kilometers, with 916 kilometers within India.
• In Tibet, it is known as the Yarlung Tsangpo.
• Its basin extends across Tibet (China), Bhutan, India, and Bangladesh.
• In India, the basin includes Arunachal Pradesh, Assam, West Bengal, Meghalaya, Nagaland, and Sikkim.
• The river enters India near Gelling in Arunachal Pradesh.
• In Arunachal Pradesh, it is called the Siang. As it flows through Assam, it is joined by several tributaries before entering Bangladesh, where it is called the Jamuna.

Tributaries:

• Right-bank tributaries include the Lohit, Dibang, Subansiri, and Teesta rivers.
• Left-bank tributaries include the Burhidihing and Kopili rivers.

River-Linking Projects:

• Manas-Sankosh-Teesta-Ganga Link: This project aims to connect the Brahmaputra River to the Ganga River via the Sankosh and Teesta rivers.
• Jogighopa-Teesta-Farakka Link: This project links the Brahmaputra River, through the Jogighopa Barrage, to Farakka on the Ganga River.

Host Riverine Island:

• The river basin is home to Majuli, the world’s largest river island, and Umananda, the smallest river island in the world, both located in Assam.

How Could Chinese Dams Affect the Brahmaputra in India?

• Hydrological Impact: The dams built by China could change the natural water flow patterns of the Brahmaputra River, which would affect how much water is available in different seasons.
• Example: One such project is the Medog Hydropower Project, which is proposed to have a capacity of 60,000 megawatts and is located near the ‘Great Bend’ of the Yarlung Tsangpo in Tibet.
• Floods and Droughts: If China suddenly releases a large amount of water or holds back water temporarily, it could lead to more severe floods or worsen drought conditions in downstream areas like Arunachal Pradesh and Assam, particularly during the dry season.
• Ecological Disruptions: The construction of these dams could lead to a decrease in sediment flow, changes in flooding patterns, and loss of biodiversity.
• Example:Kaziranga National Park, which is famous for its population of one-horned rhinoceroses, relies on regular flooding from the Brahmaputra River for its ecological health and regeneration.
• Strategic & Geopolitical Risk: China’s control over these water resources could give it an advantage in water-related diplomatic issues and could be used as a tool for pressure. For instance, during the 2017 Doklam standoff, China withheld hydrological data about the Brahmaputra River, which it is required to share under a bilateral agreement with India.
• Economic Consequences: Uncertainty in water flow due to these dams could negatively impact agriculture, irrigation, and hydropower generation in downstream areas of India.
• Example: Disruptions in tributaries like the Subansiri and Siang, where India has plans for large hydropower projects such as the Lower Subansiri Hydro Project, could delay these projects or reduce their energy output.
• Inter-State Tensions in India: Unpredictable water flow from upstream could worsen conflicts between Indian states over water sharing.

China’s Contribution Vs India’s Share

• Multiple expert studies (e.g., by PK Saxena and Teerath Mehra. indicate that China contributes only 22–30% of Brahmaputra’s annual discharge.
• 70–78% of the river’s flow is generated within India, primarily due to monsoonal rainfall and tributary inflows in Arunachal Pradesh and Assam.
• Hydrologically, China’s control over the river’s headwaters has limited influence on its overall flow in India.
• Even to address water scarcity, two river-linking projects have been proposed: Manas-Sankosh-Teesta-Ganga Link and Jogighopa-Teesta-Farakka Link.

Way Forward

• Conduct Scientific Studies: India should carry out detailed scientific research to understand the potential impacts of Chinese infrastructure projects on the Brahmaputra River. This includes assessing changes in water flow, sediment transport, and ecological effects. 
• Develop Adaptive Strategies: Based on the scientific studies, India should develop adaptive management strategies to mitigate potential negative impacts. This could involve planning for varying water availability and protecting critical ecosystems. 
• Strengthen Diplomatic Efforts: India needs to enhance diplomatic initiatives to gain access to hydrological data from China. Establishing data-sharing protocols can help in early warning systems and disaster preparedness. 
• Utilize International Forums: India can leverage platforms like BIMSTEC, Shanghai Cooperation Organization (SCO), and the Quad to raise awareness about the issue. These forums can be used to advocate for sustainable and equitable management of transboundary rivers. 
• Promote Sustainable River Management: India should work towards promoting sustainable and equitable transboundary river management practices. This includes involving local communities in decision-making and ensuring that ecological needs are met.