Siang hyropower project aimed at water storage, regulation amid China dam concerns: Arunachal Dy CM

Arunachal Pradesh Deputy Chief Minister Chowna Mein on Monday said the proposed 11,200 MW Siang Upper Multipurpose Project is primarily aimed at storing and managing water in the Siang basin, particularly in view of concerns over China's proposed mega dam on the river upstream.

Mein, who also holds the power and hydropower portfolios, took to X to say a comparison between the proposed Siang Upper Multipurpose Project (SUMP) and the reported 60,000 MW Medog project in China should not be based only on their power-generating capacities.

"Whereas the Medog Dam in China is primarily designed for hydropower generation, with an estimated head of around 2,000 metres and storage capacity of 5.5 billion cubic metres, SUMP, with a proposed dam height of around 280-300 metres and about 9.2 billion cubic metres of live storage, is primarily about storing, regulating and managing water, alongside power generation," he said.

The deputy chief minister said the distinction was important while looking at the larger purpose of the proposed project, particularly amid apprehensions over possible sudden releases or extreme flows from upstream.

"In the event of sudden releases or extreme flows upstream, this storage can help regulate downstream discharge and reduce the risk of flooding in the Siang basin and downstream areas of Arunachal Pradesh and Assam," he said, asserting that power generation was secondary to its proposed storage and water-regulation functions.

The SUMP project has been facing opposition from locals of the Siang region in Arunachal Pradesh.

Protesters have been demanding an immediate stop to the ongoing Pre-Feasibility Report (PFR) activities and survey work for the project proposed on the Siang River. They have also sought withdrawal of security forces deployed in areas likely to be affected by the proposed project.

However, the government has maintained that the 11,000 MW project would drive economic and social growth, generate employment and self-employment opportunities for the youth, and strengthen water and energy security for the state and the nation.

"In the case of SUMP, power generation is secondary. Water storage and regulation function is central to SUMP's larger purpose," Mein said.

The proposed SUMP, one of the biggest hydropower projects planned in the northeastern state, envisages construction of a large dam across the Siang river in Arunachal Pradesh. The project will be executed by power major National Hydroelectric Power Corporation. 

Mein said the project should be viewed in the context of protecting the river basin and communities living along the Siang and its tributaries. "The Siang Upper Multipurpose Project is actually intended to protect the Siang river basin and the people living along its tributaries," he said.

Mein stressed that the project has not reached a stage where a final decision on its construction has been taken.

He said the PFR is only an initial assessment to determine whether the project is technically feasible and whether it can be safely developed, pointing out that several stages of studies, consultations and statutory clearances would have to be completed before any final decision can be taken.