Arunachal's Siang Project Can Regulate China Dam Flows: Dy CM

Arunachal's multipurpose project can help regulate downstream flows from China's proposed mega dam: Dy CM

Itanagar, Oct 5

In a post on X, the Deputy CM sought to explain how the proposed SUMP could address concerns arising from the proposed mega hydropower project upstream in China, stressing that installed power capacity and water-storage capacity are two different parameters. "The question is often asked: How can the proposed 11,200 MW Siang Upper Multipurpose Project address concerns around a 60,000 MW project upstream? The answer lies in understanding that MW measures power, not water," he said.

According to Mein, the proposed Medog Dam project in China is primarily designed for hydropower generation, with an estimated height of around 2,000 metres (2 KM) and a storage capacity of about 5.5 billion cubic metres. In contrast, the SUMP is proposed to have a dam height of around 280-300 metres and about 9.2 billion cubic metres of live storage, he said.

"The SUMP is primarily about storing, regulating and managing water, alongside power generation," the Deputy CM said. He said that in the event of sudden releases or extreme flows from upstream, the storage capacity of SUMP could help regulate downstream discharge and reduce the risk of flooding in the Siang basin and downstream areas of Arunachal Pradesh and Assam.

Mein further emphasised that in the case of SUMP, power generation was secondary, while its storage and water-regulation functions were central to the project's larger purpose.

The Siang Upper Multipurpose Project, proposed on the Siang River in Arunachal Pradesh, is envisaged as a major multipurpose project combining hydropower generation with water storage and regulation. The Siang River, which enters Arunachal Pradesh from Tibet, is known as the Yarlung Tsangpo in Tibet before entering India and subsequently joining other rivers in Assam to form the Brahmaputra.

Mein's remarks come amid concerns in the Northeast over China's plans for a mega hydropower project on the Yarlung Tsangpo in Tibet and its potential downstream implications for India, particularly Arunachal Pradesh and Assam.

Meanwhile, Arunachal Pradesh Chief Minister Pema Khandu recently said that the Rs 1.5 lakh crore SUMP should not be viewed merely as a conventional hydropower project, but as a national project with wider strategic and security implications. Khandu emphasised that the issue was neither about his personal interest nor that of Prime Minister Narendra Modi, but about India's national security and defence preparedness.

Khandu reiterated that the government is not seeking to rush the SUMP beyond the feasibility stage but wants the Preliminary Feasibility Report (PFR) completed so that an informed decision could be taken on whether, where and how the proposed structure could technically be developed. "If the experts determine after the PFR that the project cannot be built, there will be no further process," he said, and highlighted that the possible economic implications of the proposed project could represent one of the country's largest investments, estimating the investment initially at around Rs 1.5 lakh crore and potentially reaching Rs 2 lakh crore.

The SUMP is a mega hydropower initiative with a proposed generation capacity of 11,200 MW, and it is a project of national strategic importance, not only for the Northeastern state but for the entire country. The SUMP is expected to significantly transform the development landscape of Siang district, whose name derives from the mighty Brahmaputra River, locally known in Arunachal Pradesh as the Siang River.

Referring to the large water infrastructure project announced by China in 2021, the Chief Minister had said India and Bangladesh had sought details and discussions from the Chinese side regarding the project and water-sharing concerns, but those requests had not been accepted. He stressed that technical clarity on the project is essential before any decision is taken on its subsequent stages.

The Chief Minister had said the PFR is expected to take only three months, covering November, December and January, after which there would be greater clarity on the feasibility, location and technical parameters of the proposed project.

— IANS