GUWAHATI, Nov 9: Assam Congress president Gaurav Gogoi wrote to Union Jal Shakti Minister CR Patil, raising concerns over the downstream impact of the proposed Siang Upper Multipurpose Project in Arunachal Pradesh on Assam.
Gogoi, who is also the Deputy Leader of the Congress party in the Lok Sabha, said the Siang River was integral to the Brahmaputra basin and sustained Assam’s agricultural economy, riverine ecosystems and livelihoods. Any major intervention in its flow required a careful assessment of flood risks, water security and its impact on downstream communities, he said.
He referred to Assam’s long-standing concerns over mega-dam projects in Arunachal Pradesh. Gogoi said former chief minister Tarun Gogoi had sought formal consultation with Assam before major dam projects were undertaken in the neighbouring state in 2014, and had withheld support for the proposed Middle Siang project in 2015 until its benefits for local communities were demonstrated.
“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,” Gogoi said.
He said the proposed project was being positioned as a strategic response to China’s proposed mega-dam on the Yarlung Tsangpo, but downstream communities in Assam must receive equal consideration. He cited concerns over sudden water releases, riverbank erosion, flooding and loss of livelihoods linked to the Lower Subansiri Hydroelectric Project, as well as a 2025 study on flooding, declining fisheries and agricultural losses.
Gogoi also cited the 2013 Cumulative Impact and Carrying Capacity Study of the Siang Sub-Basin, which identified possible ecological and livelihood impacts of earlier Siang projects, including the effects of daily winter water releases on river islands such as Kobo Chapori in Assam.
He asked the ministry to clarify whether the Assam government had been formally consulted on the project and sought disclosure of project assessments and hydrological studies. Gogoi called for an independent downstream impact assessment covering Assam, consultation with affected communities and experts, and real-time data-sharing between Assam and Arunachal Pradesh for flood monitoring and early warning.
He said no irreversible decision should be taken without prior consultation with Assam, an independent assessment of downstream effects and a transparent process that gave affected communities a meaningful voice.
