From the article:

When completed, the project - also known as the Motuo Hydropower Station - will overtake the Three Gorges dam as the world's largest, and could generate three times more energy.

Experts and officials have flagged concerns that the new dam would empower China to control or divert the trans-border Yarlung Tsangpo, which flows south into India's Arunachal Pradesh and Assam states as well as Bangladesh, where it feeds into the Siang, Brahmaputra and Jamuna rivers.

A 2020 report published by the Lowy Institute, an Australian-based think tank, noted that "control over these rivers [in the Tibetan Plateau] effectively gives China a chokehold on India's economy".

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India plans to build a hydropower dam on the Siang river, which would act as a buffer against sudden water releases from China's dam and prevent flooding in their areas.

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Chinese authorities have long eyed the hydropower potential of the dam's location in the Tibet Autonomous Region.

It's in a massive canyon that is said to be the world's deepest and longest on land, along a section where the Yarlung Tsangpo - Tibet's longest river - makes a sharp U-turn around the Namcha Barwa mountain.

In the process of making this turn - which has been termed "the Great Bend" - the river drops hundreds of metres in its elevation.

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China has been eyeing the steep valleys and mighty rivers in the rural west - where Tibetan territories are located - to build mega-dams and hydropower stations that can sustain the country's electricity-hungry eastern metropolises. President Xi Jinping has personally pushed for this in a policy called "xidiandongsong", or "sending western electricity eastwards".