GUWAHATI: Congress MP Gaurav Gogoi has written to Union Jal Shakti Minister CR Patil, expressing concern over the potential downstream impact of the proposed Siang Upper Multipurpose Project (SUMP) on Assam, even as protests against the project continue in Arunachal Pradesh.
In his letter, Gogoi said the Siang River was integral to the Brahmaputra basin and sustained Assam’s agricultural economy, riverine ecosystems and livelihoods. He said any major change to its flow required careful assessment of the implications for flood risks, water security and downstream communities.
He recalled Assam’s longstanding concerns over mega-dam projects in Arunachal Pradesh. In 2014, then Chief Minister Tarun Gogoi had called for formal consultation with Assam before major dam projects were taken up in the neighbouring state. In 2015, he withheld support for the proposed Middle Siang project until its benefits to local communities could be demonstrated, stressing the need for consultation and safeguards for Assam.
Gaurav Gogoi said that while SUMP was being projected as a strategic response to China’s proposed mega-dam on the Yarlung Tsangpo, the interests of downstream communities in Assam must receive equal consideration.
“The project’s stated objectives of maintaining year-round flows and moderating floods cannot be treated as guaranteed outcomes, particularly in a region vulnerable to extreme rainfall, landslides and glacial lake outburst floods,” the Jorhat MP said.
Citing the experience of the Lower Subansiri Hydroelectric Project, he highlighted concerns over sudden water releases, riverbank erosion, flooding and the impact on downstream livelihoods.
He also referred to a 2025 study documenting concerns among downstream communities over flooding, declining fisheries and agricultural losses. He said these experiences underlined the need for independent assessments, transparent monitoring and meaningful participation of affected communities.
Gogoi sought clarification on whether the Assam government had been formally consulted on SUMP and called for the disclosure of relevant project assessments and hydrological studies.
He also sought an independent assessment of the project’s downstream impact on Assam, prior consultation with affected communities and experts, and better coordination and real-time data-sharing between Assam and Arunachal Pradesh to strengthen flood monitoring and early-warning systems.
He urged the Centre not to take any irreversible decisions without prior consultation with Assam, an independent assessment of downstream consequences and a transparent process that gives affected communities a meaningful voice.