China breaks ground on what Premier Li Qiang has called the “project of the century”, but some fear a water conflict and ecological effects.

On the eastern rim of the Tibetan plateau, China envisions a future powered by the roaring waters of the Yarlung Tsangpo, also known as the Brahmaputra. The river will be the site of a mega dam — the world’s most ambitious to date — that promises to bring clean energy, jobs, infrastructure and prosperity to the region.

Construction on the world’s largest hydropower dam began on Saturday, according to Premier Li Qiang, who called it the “project of the century”.

But the project is not just about electricity and economic benefits – the stakes are far higher. Regional security, ecological stability and the future of one of Asia’s great rivers all hang in the balance.

How big is the mega dam?

The dam will be situated in the lower reaches of the Yarlung Tsangpo, where a section drops 2000 metres (6562 feet) over a 50km (31 miles) stretch, creating immense hydropower potential. The dam is reportedly located in Medog, a remote county in the city of Nyingchi in the Tibet autonomous region.

When completed, the project will overtake the Three Gorges Dam as the world’s largest hydropower dam. It could generate three times more energy with five cascade hydropower stations – an estimated annual capacity of 300 billion kilowatt-hours (kWh) of electricity, more than Britain’s total annual power output.

It is estimated to cost about 1.2 trillion yuan (US$167 billion), dwarfing many of the biggest infrastructure undertakings in modern history at about five times the cost of the Three Gorges Dam and even more expensive than the International Space Station.

Why is it important?

The project was first announced in 2020 under China’s five-year plan as part of a broader strategy to exploit the hydropower potential of the Tibetan Plateau, with feasibility studies dating back to the 1980s. Beijing authorised the dam’s construction in December 2024.

China is the world’s top hydropower producer, but it “is fast running out of rivers to dam”, which makes the Yarlung Tsangpo “the final frontier” for large-scale expansion, according to Trivium China, a China-focused research firm.

The Chinese Government sees the project as a national strategy with major significance for Tibet’s development and China’s clean energy targets.

By tapping into the river’s vast hydropower potential and integrating surrounding solar and wind resources, China aims to establish a clean energy hub in the region, stabilising the grid while reducing reliance on coal. This aligns with Beijing’s green energy goals and 2060 carbon neutrality targets, according to state media.

The project is also expected to boost local employment, infrastructure and livelihoods in Tibet while prioritising ecological protection through rigorous geological surveys and environmental monitoring, according to official media.

“Beyond energy security, policymakers likely also have state-building on the mind. The mega dam will anchor an unprecedented wave of industrial and infrastructure investment in Tibet – deepening Beijing’s control over the politically sensitive region,” Trivium China said on its website on Monday.

What is at stake, and why is India anxious?

The Yarlung Tsangpo flows south into India, where it becomes the Brahmaputra River, then flows into Bangladesh. Both South Asian nations have raised concerns about downstream implications of a water conflict, which could potentially affect millions of people who depend on the river for agriculture, fisheries and daily consumption.

The river flows through Arunachal Pradesh, known in China as Zangnan – a territory claimed by both China and India. New Delhi views the project as a possible means for Beijing to project power and exert control over water resources for strategic and economic advantage. India fears the potential weaponisation of water by China, which could use the dam to cause floods or induce droughts.

Earlier this month, Arunachal Pradesh Chief Minister Pema Khandu described the mega dam project as a ticking “water bomb” and said downstream Indian waters could “dry up considerably” once the dam was completed.

Observers have also raised concerns about population displacement and risks to one of the richest and most diverse environments on the plateau. Chinese authorities did not disclose how many people were likely to be displaced.

Tibetan groups have reportedly noted the presence of sacred sites along the river.

China asserts that the project has undergone rigorous scientific evaluation and will not adversely affect the environment, geological stability, or water resource rights of downstream countries. Beijing has also emphasised that it will not try to benefit at the “expense of its neighbours”.

The area where the dam is being built sits atop the Indian-Eurasian tectonic boundary, a seismically active zone, making it prone to earthquakes and leaving little margin for engineering error. Experts said it could take at least a decade to build the dam because of the technical challenges. The dam is expected to begin operations in the 2030s.

Republished from South China Morning Post, 23 July 2025

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