THREE GORGES DAM

Dam capacity is expected to drop from 6 trillion cubic metres (cu m) to 4.655 trillion cu m by 2050, and action must be taken to address the problem and protect vital storage infrastructure, the United Nations University said.

The prolonged drought in southwest China has exposed the vulnerability of hydropower-dependent regions such as Sichuan to falling water levels and disrupted electricity transmission to other parts of the country. With per capita water supplies already only a quarter of the global average, authorities are also concerned about the impact of low rainfall on the upcoming autumn harvest, with some suggesting 20% of China's crop could be affected.

Built through the 2000s just as China’s rise was at its most headlong, the world’s largest power station can generate 22.5 gigawatts, equivalent to 20 nuclear plants. Two more of the world’s six biggest generators are upstream of its reservoir on the Yangtze River. Together, they pump out enough electricity to light up Poland.

Since Tibet's occupation, China has disrupted the natural flow of rivers by pursuing a series of ill-conceived environmental and developmental policies such as the Great Leap Forward, the South-North Water Diversion Project, etc, the report said, adding that, this has led to a dam-building spree on the Tibetan plateau with disastrous impacts on Asia's major rivers.

Water levels reached historic highs in 53 rivers during China's summer last year, according to China's ministry of water resources, as authorities warned the Three Gorges Dam is facing the largest flood peak since it began operating in 2003. Here are five questions about why China still endures severe flooding every year.

Chinese President Xi Jinping congratulated the Baihetan hydropower station for launching the first two generating units, saying as a major project in China's west-east power transmission programme, the station is the largest and most technically difficult hydropower project under construction in the world.