BEIJING • China has evacuated thousands of residents after a landslide blocked a river and created a barrier lake that threatened to submerge neighbouring villages, as large parts of the country reeled under some of the heaviest rainfall in decades.
The landslide occurred on Tuesday as 1.5 million cubic m of earth fell into a tributary of the Yangtze River near Enshi city in Hubei province, Xinhua news agency said, citing local flood control authorities.
The National Meteorological Centre yesterday renewed a yellow alert for rainstorms in Shandong, Henan, Jiangsu, Shaanxi, Chongqing, Sichuan, Yunnan and Tibet as fresh rounds of torrential rain threaten to raise flood risks across the country.
The centre warned that some areas of Shandong will experience heavy rain with up to 180mm of daily rainfall, and local authorities are advised to halt outdoor operations in flood-prone areas.
Red alerts have been declared in the provinces of Anhui and Jiangxi, which are bisected by the Yangtze.
China’s Water Resources Ministry warned on Tuesday that water levels in the Yangtze and adjoining lakes would continue to rise.
Ministry officials said they needed to keep a close eye on water levels at the Three Gorges Dam, which has been storing huge volumes of water to ease downstream flood risks, and is now 16m higher than its official warning level.
China’s giant dams, designed to contain floods and generate electricity, have come under heavy scrutiny in recent weeks.
While officials have talked up their role in reducing flood peaks, critics say they not only fail to protect against extreme weather but also cut flood storage capacity. For example, a dam at a small reservoir in the Guangxi region gave way last month after days of heavy rain.
Located in Yangshuo county, the dam collapsed at around midday on June 7, inundating roads, orchards and fields in Shazixi village, residents told Reuters.
“I’ve never seen such flooding,” said villager Luo Qiyuan, 81, who helped build the dam decades ago.
“The water levels were never so high in previous years, and the dam had never collapsed.”
Completed in 1965, the dam, made of compacted earth, was designed to hold 195,000 cubic m of water, enough to fill 78 Olympic-size swimming pools and meet the irrigation needs of Shazixi’s farmers.
On a visit to the reservoir this month, Reuters found that the length of the dam – about 100m – had largely vanished. It had been reinforced 25 years ago.
The water went over the dam, which then collapsed, said a member of a survey crew at the reservoir, declining to be identified as he was not authorised to speak to the media.
Shazixi residents said there were no deaths. But the collapse, which was not reported by the domestic media, suggests big storms might be enough to overwhelm reservoirs, especially if the design is inferior and maintenance has been patchy.
That raises the prospect of disaster in river valleys and flood plains that are much more densely populated than they were when the dams were built.
Dams also block the flow of sediment and reduce the ability of wetlands to absorb flood waters, said Professor Darrin Magee from the Hobart and William Smith Colleges in New York who specialises in China’s water issues. The need to generate power can also undermine flood control efforts, he added.
“Flood control requires retaining water, and power production requires letting it out,” he said.
The Ministry of Agriculture and Rural Affairs on Monday said it has allocated a 330 million yuan (S$65.3 million) disaster relief fund to help farmers and agricultural production in southern provinces, including Jiangsu, Anhui, Jiangxi, Hubei, Hunan, Guangxi and Sichuan.
The fund would help farmers resume production after the disaster and repair damaged agricultural facilities, which will in turn reduce the loss of farm income.