How China blew up dam to ease flood risk

Chinese authorities blew up part of a dam in eastern Anhui province to relieve flood pressure, local media reported, as heavy rains continue to swell rivers across parts of the country.

Rising waters across central and eastern China have left over 140 people dead or missing, and floods have affected almost 24 million since the start of July, according to the ministry of emergency management

Authorities have adopted measures such as diverting water into back-up reservoirs to keep levels manageable as major rivers and lakes hit record highs.

In Anhui, a dam on the Chu river was demolished Sunday as water levels inched close to historic highs.

Local authorities said the action was taken to ensure the safety of people living nearby.

"Affected by continuous downpours and upstream flows, the water level of the Chu River, a tributary of the Yangtze River, has moved from a slow rise to a sharp one," local media said Monday.

The blasting of the dam was expected to reduce the level of the Chu River by around 70 centimetres (28 inches), reported the state-run Global Times.

Chinese media said the released water was being channelled into two downstream storage ponds.

Authorities are particularly concerned with Poyang Lake -- China's freshwater lake -- in hard-hit Jiangxi province.

Water levels there have hit historic highs, prompting an effort by more than 100,000 soldiers and other personnel to rescue residents and shore up dykes and levees to prevent worse flooding.

Dramatic improvement is not expected anytime soon.

A total of 35 rivers and lakes in Anhui saw high water marks exceed warning levels by Saturday noon -- including the Yangtze and Huaihe rivers -- reported the official Xinhua news agency.

Waters in more than 400 rivers have exceeded warning levels, while some have reached historic highs over a period that officials say has caused the highest average rainfall levels across the Yangtze basin since 1961.

Summer rains and seasonal glacial melt in the river's Tibetan plateau headwaters cause routine annual flooding.

Over the weekend the Three Gorges Dam also opened three floodgates after the water rose more than 15 metres above flood level.

Heavy rains since June have left at least 141 people dead and missing, forced nearly 15 million people to be evacuated from their homes in July alone, and caused billions of dollars in economic losses, according to the government.

Last week soldiers erected sandbag flood barriers in a city near China's largest freshwater lake after the heaviest rainfall in nearly six decades drenched the Yangtze River basin.

Vast swathes of China have been inundated by the worst flooding in decades along the mighty Yangtze River, with residents piling into boats and makeshift rafts to escape a deluge that has collapsed flood defences and turned their homes into waterways.