Archive for May 25th, 2011

May 25, 2011

China crisis over Yangtze river drought forces drastic dam measures

Severe drought has forced China to release 5bn cubic metres from Three Gorges reservoir for irrigation and drinking water

View Original Source:  http://www.guardian.co.uk/environment/2011/may/25/china-drought-crisis-yangtze-dam

The dried up Yangtze river in southwest China's Chongqing municipality. The severe drought has forced a massive release of water from China's Three Gorges reservoir for irrigation and drinking water. Photograph: STR/AFP/Getty

The Yangtze – Asia’s biggest river – is experiencing its worst drought in 50 years, forcing an unprecedented release of water from the Three Gorges reservoir. The drought is damaging crops, threatening wildlife and raising doubts about the viability of China‘s massive water diversion ambitions.

Between now and 10 June the dam will release 5bn cubic metres of water – equivalent to the volume of Lake Windermere in Britain every day – as engineers sacrifice hydroelectric generation for irrigation, drinking supplies and ecosystem support.

The drastic measure comes amid warnings of power shortages and highlights the severity of the dry spell in the Yangtze delta, which supports 400 million people and 40% of China’s economic activity.

From January to April, the worst hit province of Hubei has had 40% less rainfall than the average over the same period since 1961. Shanghai, Jiangsu and Hunan are also severely affected.

Regional authorities have declared more than 1,300 lakes “dead”, which means they are out of use for irrigation and drinking supply. Shortages affect 4.4 million people and 3.2 million farm animals, according to the Office of State Flood Control and Drought Relief Headquarters.

The narrowing and shallowing of the Yangtze and its tributaries has stranded thousands of boats and left a 220km stretch off limits for container ships.

The central government has dispatched water pumps and diesel generators to Hubei and Hunan to ease the impact. This is expensive and adds to the pressures on China’s energy supply system at a time when the state grid authorities are warning of the worst summer power cuts in seven years.

“The primary cause of this drought is a lack of rainfall. But we can also be certain that the Three Gorges dam has had a negative impact on the water supply downstream,” said Ma Jun, founder of the Institute of Public and Environmental Affairs. “This is a reminder that the water in the Yangtze is not unlimited. We cannot bet everything on this river. We need to focus more on conservation.”

Desperate farmers are pumping water from nature reserves, prompting alarm among conservationists about the loss of habitat for several endangered species including the finless porpoise – the last remaining cetacean on the Yangtze after the demise of the baiji dolphin.

At the Swan Island national nature reserve the depth is three metres lower than last year – which was then a record low. According to Wang Ding, a dolphin expert at the Hydrobiology Institute under the Chinese Academy of Sciences, the habitat of a pod of 30 porpoises has halved in length from 21km to 10km.

“Finless porpoises cannot survive if the level continues to drop,” Wang told Xinhua news agency. “If the activity area is reduced they might be stranded on the bank and will die if they can not swim back.” There are believed to be 1,000 porpoises left in the river.

The authorities have attempted cloud seeding to induce rain but a brief shower at the weekend was far from enough. China’s meteorological administration sees little prospect of rain before the end of the month and says temperatures in the affected region could rise to 36C.

To minimise the impact, the Three Gorges authority has been instructed to open the sluice gates. It has already discharged 1.8bn cubic metres of water this month, taking the level of the reservoir below 153m from a peak of 175m.

The dam’s role in the drought has been the subject of a fierce debate. Downstream communities have accused the Three Gorges of holding back too much water to generate power. Environmentalists say this has contributed to the demise of lakes and wetlands, which are already under pressure from urban development and the demands of agriculture. The operators, however, say the reservoir is helping to ease shortages through a timely release of water.

Last week the state council – China’s cabinet – acknowledging that Three Gorges faces “urgent problems” of geological disaster prevention, relocation and ecological protection. It noted the negative impact on downstream water supplies and river transport.

The dam is not the only hydro-engineering project that has come under scrutiny as a result of the drought. The state’s massive south-north water diversion project, which aims to tap the normally moist Yangtze basin to supply arid northern cities like Beijing, is also being called into question because one of its source reservoirs at Danjiangkou has fallen 4m below the minimum requirement for its operation.

“This is bound to have an impact on the diversion project,” said Zhang Junfeng, an environmental activist with Green Earth Volunteers. “Water storage at Danjiangkou reservoir is already at a dead level and I think the situation will get worse year by year because this is partly due to climate change.”

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May 25, 2011

China power crunch to worsen as drought slashes hydro output

View Original Source:  http://af.reuters.com/article/energyOilNews/idAFL3E7GP15V20110525?sp=true

Wed May 25, 2011 9:24am GMT

* Hydro output in Yangtze region plunges

* Reservoirs releasing water to ease drought

* Hydro-rich provinces looking for replacement fuels (Adds impact on rice yields, background)

By David Stanway

BEIJING, May 25 (Reuters) – The worst drought to hit central China in half a century has brought water levels in some of the country’s biggest hydropower producing regions to critical levels and could exacerbate electricity shortages over the summer.

The official Xinhua news agency said on Wednesday that the water level at the world’s biggest hydropower plant at the Three Gorges Dam in Hubei province has fallen to 152.7 metres, well below the 156-m mark required to run its 26 turbines effectively.

Total capacity at the Three Gorges hydropower project amounts to 18.2 gigawatts, the equivalent of about 15 third-generation nuclear reactors and more than a third of Hubei’s total. It generated 84.4 billion kilowatt-hours of electricity in 2010, delivering power as far afield as Shanghai on the eastern coast.

The water level is expected to fall further to around 145 metres by June 10, when planned discharges are scheduled to end.

The drought has struck at the time of year when China’s hydropower output would normally surge. Hydro output bottoms out in January and February and peaks over the summer. During six months of last year, from May to October, 20 percent of China’s electricity generation was hydropower.

High temperatures and record low rainfall in 2011 have caused water levels on the middle and lower reaches of the Yangtze River to dwindle, cutting support to thousands of hydropower plants as well as millions of hectares of farmland.

Official figures from Hubei province earlier this week showed that 1,392 reservoirs in the region are now too depleted to generate any electricity at all.

Water levels on the Yangtze midstream are 6 metres lower than they were the same time last year, with rainfall only a fifth of the levels seen in 2010, according to the China Daily newspaper, quoting local drought relief agencies.

China’s meteorological administration said on Wednesday that average rainfall in Anhui, Jiangsu, Hunan, Hubei, Jiangxi, Zhejiang and Shanghai is the lowest since 1954.

The Three Gorges reservoir has already released more than 17 billion cubic metres of water downstream, and analysts expressed hope that the move will ease the problems facing downstream rice planters in Hubei and elsewhere.

The affected provinces of Hubei, Hunan, Jiangxi, Anhui and Jiangsu together accounted for 47 percent of China’s total rice output in 2010, according to China’s Agricultural Yearbook.

“With the Three Gorges Dam now releasing water to downstream provinces, the drought will be eased to some extent and it may not cause any damage to the early rice harvest,” said Ma Wenfeng, an analyst with Beijing Orient Agribuiness Consulting Co.

China is such a large country that virtually every year some part of it is hit by disastrous droughts or floods, many of them caused by fluctuations in the Yangtze, the country’s longest river stretching from Tibet to Shanghai.

Nearly 10 million people, mainly in the Yangtze farming heartlands, have been affected by the 200-day drought so far, and several Jiangxi tributaries normally used by fishermen in rowing boats have now completely dried up, China Daily reported.

The early harvest usually accounts for only a fifth of total annual rice output, he said, adding that some planters might have delayed their activities until the second mid-year harvest beginning in June, when the rain season begins.

POWER DEFICIT

The release of water from the Three Gorges and thousands of other reservoirs in the region might help beleaguered local farmers, but it could be bad news for industries dependent on hydropower supplies.

“Fundamentally there is a conflict between hydropower generation and water supply, irrigation, and navigation,” said Ma Jun, of the Institute of Public and Environmental Affairs (IPEA), a non-government organisation that monitors China’s rivers.

China is facing historically high power shortages as the summer consumption peak approaches, and lower water flows in major hydropower producing regions like Hubei and Hunan are expected to put more pressure on coal and diesel supplies as they search for alternative sources of fuel.

PetroChina has already supplied 18.6 percent more diesel than a year earlier to Hubei to help the province combat the drought, its parent CNPC said in a company newspaper on Wednesday.

Hydropower utilisation rates in Hunan fell 55 percent in April, according to analysts from Dongfang Securities, and traders said the impact was already being felt by local industry.

“By yesterday almost half of all silicon-making facilities (in Hunan) had been suspended because of the lack of electricity,” said a Shanghai-based trader.

Aluminium and copper smelters in the region could also suffer, especially if scarce coal supplies are diverted to meet residential power needs, another trader said.

Hydropower will be a crucial component in China’s energy strategy in the coming decade as it tries to reduce its dependence on coal, and plans are under way to put an additional 140 GW of capacity under construction by 2015.

But the drought has drawn attention to the impact that big dam construction programmes have had on China’s river systems, including the Yangtze and its tributaries.

Government experts have rejected widespread claims that the Three Gorges reservoir has worsened the risk of drought in the region, saying that the current crisis has been caused by unfavourable global weather patterns.

But Ma of IPEA said the 600 sq km reservoir has disrupted water flows and made it harder to supply downstream regions.

“Without the Three Gorges Dam, the water level in the Yangtze would not be that low,” he noted. (Additional reporting by Niu Shuping in Beijing and Ruby Lian in Shanghai; Editing by Ken Wills)

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