The bureaucratic impetus for the 11.2-GW Siang Upper Multipurpose Project (SUMP) in Arunachal Pradesh purportedly comes from China’s aggressive development of a 60-GW mega-dam in Tibet, stoking anxieties among Indian authorities over ‘weaponised’ transboundary waters. Beijing may be able to divert flows in the Yarlung Tsangpo river, which becomes the Brahmaputra in India, to cause drought downstream or release water en masse to trigger catastrophic floods in Arunachal Pradesh and Assam.
New Delhi thus imagines SUMP as a strategic buffer, but in so doing faces a dilemma it should not attempt to resolve with force. Its extant top-down approach, exemplified by deploying security forces to guard survey teams and imposing the State Unlawful Activities (Prevention) Act against activists, only validates fears among locals that the state will grab their land.
The region also hosts sustained protests against the Subansiri Upper Hydroelectric Project, expanding the indictment to Arunachal Pradesh’s model of hydroelectric power development. The eastern Himalayas are among the most tectonically active and erosion-prone landscapes in the world.
The mega-dam in Tibet will comprise five cascading power stations over the river’s roughly 2,000-metre fall over 50 km. Beijing has maintained the dam will not harm countries downstream but has declined to share crucial engineering details.
This is why diplomacy will be an essential part of operating SUMP, in addition to Beijing’s disputed claims on Arunachal Pradesh.The Brahmaputra basin in Assam and Bangladesh receives most of its water from monsoon rains and tributaries downstream of the Tibetan Plateau, so China cannot straightforwardly control the river’s total flow through India. Yet since Chinese interventions would have greater consequences closer to the border, SUMP will need information about both the mega-dam’s operations and downstream inflows to plan its own operations, and Beijing has declined to share the former.
SUMP thus faces many uncertainties at the outset. Despite India repeatedly raising the issue with China at the highest levels, headway has been limited to Beijing agreeing to share hydrological data on humanitarian grounds during emergencies.
Planners have contemplated maintaining the SUMP reservoir at 70% to accommodate unexpected surges, but the level of protection possible if China supplies no advance warning remains unclear. This uncertainty is a thorn in the side of the government’s push against more legitimate resistance by Adi community members and civil rights groups.
The need for the project does not excuse the state from following all the relevant laws and protections. The state cannot protect the nation’s needs by antagonising the nation’s people.
Published - November 03, 2026 12:56 am IST