Why China's neighbors are concerned about China's new mega-dam project

China has begun construction on the $170 billion project it claims will be the largest hydropower plant in the world. The project is estimated to cost $170 billion and generate enough electricity per year to power Britain.

After Premier Li?Qiang announced the scheme on the weekend, Chinese construction and engineering shares surged.

The project will bring clean energy, jobs, and a boost to a slowing Chinese economy. It also stirs up old fears about water security for neighbours downstream: the Yarlung-Zangbo will become the Brahmaputra, which is a lifeline to millions of people in India and Bangladesh.

WHAT DID CHINA APPROVE EXACTLY? Five dams are planned along a stretch of 50 km where the river drops 2,000 metres off the Tibetan Plateau. The first power generation is anticipated to begin in the early to mid 2030s. However, beyond the cost and timeline, China has not released much information on how the project will be built.

WHY ARE NEIGHBORS CONCERNED? The lack of information has exacerbated fears over water security for India and Bangladesh. Both countries rely on Brahmaputra water for drinking, irrigation and hydropower.

Chief Minister of Arunachal Pradesh (India, bordering China) said in an earlier statement that the dam would dry up 80% of the river flowing through the state, and could potentially flood downstream areas, such as the neighbouring Assam. Michael Steckler of Columbia University says that the dam will not only reduce water flow, but also sediment. That sediment carries nutrients essential for agriculture on floodplains downstream.

India and China fought in this area in the 1960s a border conflict. The lack of transparency by Beijing has fuelled speculation that it could use the dam to cut water during another conflict.

The construction of the Yarlung-Zangbo hydropower plant is within China's sovereign domain, said the Beijing Foreign Ministry on Tuesday. It added that the dam will provide clean energy and help prevent flooding.

The ministry stated that "China has also conducted the necessary communication with downstream nations regarding hydrological information and flood control, as well as disaster mitigation cooperation in relation to the Yarlung-Zangbo Project."

The Indian foreign and water ministers did not reply to any requests for comments.

Will it starve India of water?

Modak said that the impact of the Brahmaputra dam on downstream flows was overstated. This is partly because most of the water entering the Brahmaputra comes from rainfall south of Himalayas and not China.

He said that China has plans for a hydropower project called "run of river", which would mean the water would flow along the normal course of the Brahmapu

India has proposed two dams along the Siang River, which is its name for Yarlung Zangbo. If it is built, the 11.5-gigawatt Arunachal Pradesh project will be India's biggest. Modak said that the projects were proposed in part to assert India's claim on the river, and to bolster India's case should China attempt to divert water.

He said that China could not unilaterally divert the water if India could prove it had been using them.

CONTROVERSY is a common occurrence

Water security and dam disputes are nothing new. Pakistan accuses India of weaponising water shared in the disputed Kashmir area after New Delhi halted its participation in Indus Waters treaty which regulates the sharing of water between neighbours. A senior Egyptian politician was caught on camera suggesting to bomb the controversial Nile River dam planned by Ethiopia in a long-running dispute about the project.

EARTHQUAKE RISKS AND EXTREME WINTER RISKS: The dam is to be built in a zone prone to earthquakes, landslides and glacial-lake flooding. Experts are concerned about the safety of the dams being built in this area after a devastating earthquake that struck Tibet earlier in 2014. Due to engineering challenges and harsh winters in high altitudes, a much smaller hydropower plant on a nearby river has only been able to be built for four months.

(source: Reuters)