(TibetanReview.net, Jun20’26) – India is monitoring with high alarm the site in Tibet where satellite imagery and intelligence inputs reveal a sharp acceleration in China’s construction of the world’s largest hydroelectric dam in a seismically active area on the Yarlung Tsangpo river, just 50 kilometres from its Arunachal Pradesh state border, said Indian media reports Jun 18-20. New Delhi is also taking measures to counter what China may throw at it through this dam in potential future conflict situations.
Reportedly the world most expensive infrastructure project ever, the massive 1.2 trillion-yuan (($167-170 billion) Medog Hydropower Station features a five-stage cascade system. It sits at the world’s highest river’s dramatic U-turn before it enters India’s Arunachal Pradesh state as the Siang River and flows into Assam as the Brahmaputra before continuing it course into Bangladesh.
India fears that Beijing could weaponize water flow, disrupt fragile downstream ecologies, and also alter critical flood patterns. It is not only raising diplomatic objections but also aggressively reinforcing its own Northeast infrastructure and flood-warning networks to counter the upstream potential threat, noted english.punjabkesari.com Jun 18.
The Brahmaputra system is the lifeblood of Northeast India, sustaining agriculture, biodiversity, and millions of lives. Experts warn that a project of this scale — which will dwarf the Three Gorges Dam, the existing world’s largest — will severely disrupt natural sediment transport and water cycles.
Central to India’s anxiety is stated to be a “water bomb” scenario: during a geopolitical standoff, Beijing could choke water supplies during dry seasons or release massive volumes during monsoons, triggering catastrophic, artificial floods in Arunachal Pradesh and Assam.
So, while Beijing claims the project is purely for hydropower and carbon neutrality, New Delhi is taking no chances. The issue has been flagged at the highest levels, including during External Affairs Minister S. Jaishankar’s recent multilateral meetings, the report said.
The project will route water through 50 kilometres of tunnels, cutting directly into Mount Namchag Barwa. With water dropping over 6,500 feet, this massive 60-gigawatt, five-dam cascade system will generate 300 billion kilowatt-hours annually—three times the output of the Three Gorges Dam.
In direct response to the Chinese dam being built in Tibet, India is pushing forward with the Siang Upper Multi-purpose Project (SUMP), an 11,000 MW hydroelectric and flood-control mega-dam proposed on the Siang river in Arunachal Pradesh’s Upper Siang and Siang districts.
SUMP would become India’s largest hydropower project if built, generating an estimated 47 billion units of electricity annually at a projected cost of approximately US$13 billion (roughly Rs 1.5 lakh crore), said ndtv.com Jul 19.
India is trying to accelerate this strategic response, which is currently, firmly in pre-feasibility studies, while closely monitoring Beijing’s every move on the contested river, the report said.
Beyond power generation, SUMP, which is much smaller than the Chinese project in Tibet, is specifically designed to control seasonal flooding downstream and protect Indian territories from the risks posed by upstream diversions, a dual purpose that highlights its geopolitical significance as much as its economic value, the report added.
New Delhi is simultaneously strengthening flood forecasting systems, river monitoring networks and infrastructure resilience across the Northeast to manage risks in the interim.