As protests hit Upper Siang project, NHPC to fast-track selection of site

On May 20, NHPC had moved drilling equipment to a proposed site near Beging in Arunachal Pradesh’s Siang district. The drilling is required to finalise the pre-feasibility report, a task assigned by the ministry to the NHPC in April 2022. However, following protests by residents, whose homes and farmlands are likely to be affected by the dam, the drilling is yet to begin.

The detailed project report (DPR) — needed to obtain regulatory clearances and begin civil works — is prepared after the PFR.

“NHPC has stationed its manpower near the (proposed) project site and mobilised required resources to expedite the vital investigation required for firming up the final site,” the official said. Besides Beging, the proposed sites include Ugeng and Dite Dime.

The Jal Shakti Ministry did not respond to requests for comment on the issue.

In December 2024, China approved its 60 GW project in Medog County, on the Yarlung Tsangpo river, shortly before it enters Arunachal Pradesh as the Siang, which forms the Brahmaputra further downstream. The Upper Siang project, with a proposed large storage capacity, is expected to act as a buffer by regulating water flow and protecting downstream populations and infrastructure.

“Strategic storage on Siang River can act as a regulating scheme to mitigate adverse impact of both acts of water diversion and artificial floods by the upstream Chinese development,” the NHPC official said. “The regulated flow downstream is critical for shielding the population, infrastructure, ecology and navigation etc. from the adverse impact of Chinese development in Tibet Autonomous Region. Additionally, this strategic storage shall also enhance the renewable energy in the grid,” the official said.

While about 30 per cent of the Brahmaputra’s flow originates in China, most of it comes from rainfall within India’s catchment areas. Hence, China’s dam is expected to have a greater impact on the river’s upper stretches in Arunachal Pradesh.

Last month, while addressing the protests against the project, Arunachal Pradesh Chief Minister Pema Khandu had said: “Where hydropower is concerned, we will do what the people say if they have an objection. However, the Upper Siang project is not just hydropower. We have to understand that it is a defence mechanism.”

“India should also go for a massive dam quickly,” a senior official said on condition of anonymity, citing the risks posed by China’s project. Beyond flood concerns, the Chinese dam could also disrupt water flow to proposed downstream projects in Arunachal Pradesh.

While the Upper Siang project has been under consideration for several years, NITI Aayog, in 2017, proposed building massive storage of 9.2 billion cubic metres, saying “hydro-electric projects being envisaged on Siang river would become unviable if non-monsoon flow decreases because of unforeseen reasons”.

The Northeast holds nearly half of India’s 133 GW hydropower potential, over 80 per cent of which remains untapped. Of the 60 GW estimated potential, about 50 GW lies in Arunachal Pradesh alone.

“Once a massive dam with very large storage is constructed, it will take care of most of the issues likely to be faced by downstream projects. Further, downstream projects should also be planned with reasonable storage as per cost-benefit analysis,” the senior official said.

The PFR and DPR for the Upper Siang project are funded under the Jal Shakti Ministry’s Investigation of Water Resource Development Scheme. Once completed, it would be India’s largest hydropower station.