Chinese Premier (or Prime Minister) Li Qiang officially started the construction of a new hydropower project on the lower part of the Yarlung Tsangpo river in Tibet on Saturday. He also announced the creation of a new company called China Yajiang Group, which will be responsible for building and managing the dam, as reported by China’s official news agency, Xinhua.

The Yarlung Tsangpo River starts in western Tibet, near Mount Kailash, at a glacier in the Himalayas. It flows for about 2,900 kilometers (1,800 miles) in total.

• In Tibet, it travels around 1,700 km, flowing eastward across the high plateau.
• Then it enters India through Arunachal Pradesh, where it is called the Siang River.
• As it flows into Assam, it becomes the Brahmaputra River.
• It continues west and then south through Bangladesh, where it’s called the Jamuna River.
• Finally, it joins the Ganges River and flows into the Bay of Bengal through a vast delta.

Indian States and Places Dependent on It:

• Arunachal Pradesh (Siang River) – provides water for local communities and biodiversity.
• Assam (Brahmaputra River) – supports agriculture, drinking water, transportation, and fishing.
• West Bengal (as part of the Ganga-Brahmaputra delta) – supports farming and water needs.

This river system is crucial for millions of people living in these regions.

While many details about the new dam in Tibet are still not clear, the huge cost gives an idea of how big the project will be. It is expected to cost over $167 billion, which is more than four times what China spent on the Three Gorges Dam—a major dam project that cost around $37 billion when it was completed in 2009.

The dam project is expected to give a big boost to the economy, especially to industries like construction, cement, and steel. It will also create a large new source of clean electricity, which could help China reach its goal of producing no extra carbon pollution (net zero) by the year 2060.

What is the Three Gorges Dam?
The Three Gorges Dam is the world’s largest hydroelectric power station, built across the Yangtze River in China. It helps produce electricity and control floods, but also caused major environmental and social changes, including the relocation of over a million people.

There are also some risks. The dam could create problems between China and India because the Yarlung Tsangpo River flows into Arunachal Pradesh in northeast India. From there, it becomes one of India’s main rivers and later flows into Bangladesh. Any changes China makes to the river could affect the water supply in both India and Bangladesh.

Environmental experts in China have been worried for a long time about the damage a dam could cause in the Yarlung Tsangpo gorge. In this area, the river drops sharply—about 2,000 meters (6,560 feet) over just 50 kilometers (31 miles). This region has a national nature reserve and is one of China’s richest areas for wildlife and plants. Building a dam here could cause permanent harm to the environment.

The Yarlung Tsangpo gorge is located in southeastern Tibet, near the border with Arunachal Pradesh, India. It is considered the deepest gorge in the world, even deeper than the Grand Canyon (located in the United States). A gorge means a deep, narrow valley with steep sides, usually formed by a river cutting through mountains. This area is full of forests, rare plants, and wildlife.

There are also difficulties in building the dam because it is in a faraway and hard-to-reach place. Bringing construction materials and workers to the site is not easy. The dam will produce a large amount of electricity using the power of flowing water (called hydropower). To make sure this electricity reaches cities, villages, and factories across China, the government must build long power lines. Setting up these power lines in such a remote and hilly area will cost a lot of money and effort.

Beijing has said that the dam will not cause any harm to areas downstream—like parts of India and Bangladesh. (Downstream means the areas that are located further along the river, where the water flows after passing through the dam.) The Chinese government has also promised to take steps to protect the environment and make sure everything is safe for people and nature living along the river.

According to Xinhua, the project will have five connected dams (called cascade dams) and will be built near the city of Nyingchi in southeast Tibet. Government engineers say the Yarlung Tsangpo gorge has the power to produce up to 70 gigawatts of electricity. That’s more than three times what the Three Gorges Dam makes and even more than the total electricity used by the entire country of Poland.

What are cascade dams?
Cascade dams are a series of dams built one after another along the same river. Each dam is placed at a lower point than the one before it, like steps going down. Water flows from one dam to the next, and each dam can produce electricity using the moving water. This setup helps to use the river’s full energy potential and can also help manage floods and store water more effectively.

It’s not yet clear how the Yajiang Group will arrange the money for this massive and very expensive project. But since China has a long history of giving loans for dam projects, and the electricity made from the dam can be sold to earn money and repay those loans, it’s unlikely to become a big problem.

Earlier this year, China’s top planning body—the National Development and Reform Commission—mentioned in its yearly report that a dam will be built on the lower part of the Yarlung Tsangpo River in Tibet. It also said that power lines will be set up to carry electricity from the dam all the way to the Hong Kong region.

—E.O.M

(Girish Linganna is an award-winning science communicator and a Defence, Aerospace & Geo.political Analyst. He is the Managing Director of ADD Engineering Components India Pvt. Ltd., a subsidiary of ADD Engineering GmbH, Germany. Contact: girishlinganna@gmail.com)