On Saturday, China began building what is expected to be the world’s largest dam. The dam, which is in Tibet, will produce massive amounts of electricity. But it has upset people in India and Bangladesh, who are worried about how the dam will affect them.
The Yarlung Tsangpo is a long river that runs from China’s Tibet into India (where it is called the Brahmaputra), and then on to Bangladesh. In Tibet, the river is largely fed by melting snow and glaciers. In India, it is fed further by monsoon rains.
The river runs through the Yarlung Tsangpo Grand Canyon, which is the biggest and deepest canyon in the world. At one point, in an area of Tibet called Nyingchi, the river makes a sharp turn called the “Great Bend”. For over 30 miles (50 kilometers) along this area, the river drops by about 1.25 miles (2 kilometers).
China plans to take advantage of the power of this falling water to build the world’s largest dam*. In fact, it’s not just a single dam, but five dams. The plans also call for four 12.5-mile (20-kilometer) tunnels through a mountain.
The dam is expected to cost around $167 billion. It isn’t expected to start operating before 2033. But once it starts running, China believes the dam will provide about 300 million megawatt hours of electricity a year.
That’s enough to meet the average yearly energy demands of about 28.5 million US homes. Of course, the electricity will be used in China. But it’s three times as much power as China’s Three Gorges Dam, which is currently the world’s largest dam.
India and Bangladesh are both concerned about China’s massive project. The dam is very close to China’s border with India, where the water from the river is hugely important to millions of people. And as the river continues into Bangladesh, it feeds other rivers, which could also be affected.
Pema Khandu is the leader of Arunachal Pradesh, the Indian state that the river flows into. He’s worried that the rivers could “dry up” once China’s dam becomes active. Outside experts agree that the dam would give China a lot of control over an important Indian resource.
China says it has thought carefully about the dam and its neighbors. It says the water is designed to flow through the dam, not be stopped by it. But not everyone is convinced.
Mr. Khandu is also concerned that China could cause a flood in India by suddenly releasing lots of water from the dam. Since the dam is being built in an area where earthquakes are common, many people worry that this could also happen by accident. India is planning on building a dam of its own that could stop a sudden rush of water coming from up the river.
And even though hydropower is cleaner than burning oil or gas, there are serious concerns about how the dam will affect the environment. Rivers provide important habitats and the dam project could put special animals and plants in this remote region in danger.
