National Hydroelectric Power Corporation (NHPC) has submitted a pre-feasibility report to the Central Electricity Authority of India for the ‘Upper Siang Multipurpose Storage’ (11 GW), India’s largest hydel power project to date to come up in Arunachal Pradesh.

According to the reports, the hydel power project that is central to counter China’s ambitious water diversion scheme of the Siang river that feeds downstream into the Brahmaputra is expected to be constructed as a joint venture with state-run NEEPCO or the government of Arunachal Pradesh. The PFR was submitted to the government on 30 December 2022.

The production of hydel power from the project is “simply a byproduct”, pointing out that the main purpose of the project is to counter China’s water diversion scheme to the Yarlung Tsangpo river in China – which flows into Arunachal as the Siang and then as the Brahmaputra in Assam.

China is building a new dam in Tibet on a tributary of the Ganga, close to the tri-junction of its borders with India and Nepal, that could be used to control the flow of water downstream, new satellite imagery has revealed.

“China is building several hydroelectric projects on the Tsangpo. But one of the biggest is a 60 GW dam which is being constructed, and it is on the neck of Arunachal Pradesh in Medong. It is a part of China’s ambition to achieve carbon neutrality by 2060, but also to divert water to northern China which is water scarce. This is a major concern for India, as the diversion of water will lead to a thinning of the river water during our peak season. As well as a possible release of water will lead to major flooding,’’ said a senior official.

It also comes at a time when satellite imagery has shown that China has substantially ramped up creation of military and dual use infrastructure and villages in the eastern and western sectors of the LAC.

Satellite images tweeted on Thursday by Damien Symon, a geospatial intelligence researcher at the Intel Lab, showed earth development and dam construction activity done by the Chinese side on Mabja Zangbo river in Burang county of Tibet since May 2021.

According to the latest satellite images, the dam appears to be 350 metres to 400 metres long, Symon said.

“The structure is currently in development, so the purpose is unknown,” he said.

“It appears to be an embankment dam,” he added.

The dam can also be used to store water, whose release could create floods downstream, the people said.

In recent years, China has built several smaller dams on the Yarlung Zangbo river, triggering similar concerns related to the Brahmaputra in the northeast.

India’s solution to the problem is the Upper Siang project, which will act as a reservoir. In the event of a diversion of water by China, the massive reservoir will be able to feed Arunachal Pradesh and its irrigation requirements said officials.

According to reports, India may spend ₹1.13 trillion to build the Upper Siang multi-purpose storage project at Yingkiong in Arunachal Pradesh.

The storage project will be able to store 9-10 billion cubic metres (BCM) of water.

The 2000 MW Subansiri Upper hydroelectric project is expected to be completed in the next few months and commissioned by August 2023. Further, the Upper Subansiri, Middle Subansiri and the Lower Siang hydro projects are underway with a cumulative capacity of 66 MW.

The official also said that the Dibang Multipurpose Project on the Dibang River with a capacity of 28.8 GW is expected to get the approval of the Public Investment Board (PIB) soon. The estimated cost for the project is nearly ₹32,000 crore and is expected to be completed within a timeframe of nine years after approval from the cabinet.

Image source: Reuters