The biggest dam in the world, the Three Gorges in China, has started to turn the Yangtze into a 480 km long reservoir. As the water rises, Building considers the tasks still facing the Chinese: completing the dam and building three cities for 1.2 million displaced people
The old banks of China’s mighty Yangtze river are disappearing. Since the first weeks of June, river levels have been rising 135 m over a 480 km stretch, to form the reservoir for the world’s biggest hydroelectric power and flood control project, the Three Gorges Dam. The dam is the realisation of a 100-year old dream and a decade of hard labour – an epic engineering feat that will make the Great Wall look like a cycle lane.
The Three Gorges Dam is the centrepiece of the Chinese government’s national economic strategy. When fully operational, it is hoped that it will power the resurgence of central China, an area largely forgotten during the east coast boom of the past decades. The 2 km long dam will produce the equivalent output of 18 nuclear power plants to feed the frenzied industrialisation of nine central provinces that make up the Yangtze Economic Region.
Constructing Three Gorges has not been a building project so much as a military operation. The 10-year process has required an army of 250,000 workers, 60,000 of whom have been working in the Yangtze’s dry riverbed, pouring concrete for the main dam and building the 13 cities that will house the 1.2 million people displaced by the reservoir.
Although the dam and the cities are separate projects, it is hard to distinguish between them – the sites blur together and the workforce seems to go where it’s required. Work on the main dam does look more methodical and professional than work on the cities, however. The main dam is more or less finished, but less critical jobs continue; it’s startling to see thousands of people chiselling little rocks to fit into the jigsaw of secondary, but sizeable, embankment walls. And in the new cities, roads, bridges and housing are incomplete.
Few Western firms have been involved with the project, although some are understood to have supplied turbines and power-generating equipment. This is in part because the World Bank refused to back the scheme, and the US government warned American businesses not to get involved. As a result, nearly all aspects of construction, engineering and consultation have been run by the gigantic state-owned business entity, the China Three Gorges Project Corporation.
On the scaffolding around one new town, women work alongside men breaking rocks and carrying stacks of bricks. Only the lucky ones wear hard-hats – most are either bareheaded or sport wickerwork headgear; instead of steel-capped boots, most workers wear sandals or plimsolls. Planners working for the government insist that safety arrangements are paramount, but it is alarmingly easy to stroll on-site, and workers eager to practise their English offer cups of tea and cigarettes to tourists.
Graft goes on throughout China’s unforgiving cycle of seasons. Work during the wet months is the most difficult. Roads are washed away and the planks linking different levels are slippery and dangerous. Even walking around site in hiking boots is tough, and it’s difficult to imagine doing so wearing cotton slippers and carrying a basket of rocks.
The age range of the workers is immense; 15-year-old boys drive small tractors past chain-smoking geriatrics chiselling rocks by hand. Nobody is spared the hard stuff, though, and you see plenty of old women lugging heavy materials. The working day starts between five and six in the morning and grinds on until after dark, stopping only for rice and a nap at noon. Most labourers live on site, sleeping anywhere they can in the shanties of tarpaulin. The younger men look strong, but the middle-aged look old before their time.
The strangest aspect of the Yangtze building sites is the barely controlled hysteria created by the Sars crisis. Masked workers operate heavy machinery while men in white coats wander among them testing their temperature and spraying everything in sight with watered-down disinfectant. At the same time, sprawling rubbish tips swell and women cook rice beside broken sewers. But for most workers Sars is a hassle rather than a threat. During a recent national week-long holiday, migrant workers were not allowed to travel, which meant most kept working.
Machines are common, but not ubiquitous – they are used for the bigger jobs. As such, the quality of construction varies enormously and even the Chinese government is tentative about calling it more than “generally good”.
The dam’s price-tag is said to be £12bn, and the total investment £30bn – in reality, though, the cost is unquantifiable. Besides the destruction of the homes of 1.2 million people, some 8000 archaeological sites will be submerged, and hundreds of endangered species will be brought to the point of extinction.
Perhaps the most lamentable effect is the humbling of the Yangtze’s Three Gorges themselves. These loomed over a 200 km series of bends, forming a corridor of sheer limestone crags and dagger-like peaks. For thousands of years, these formations – with names like Sleeping Pig Rock and Yellow Cat Gorge – have inspired Chinese poets and painters. During the next few weeks, the rising tide will change them forever.
And it is not just culture that has been destroyed; the bloating Yangtze River itself is in danger. While the production of hydroelectric power is intended to be clean and to help reduce China’s reliance on coal, it is feared that slowing the river will impair its ability to oxygenate. Already one of the dirtiest stretches of water in the world, the level will add the leftover debris of millions of homes and factories to the untreated sewage.
The locals are ambivalent about this government-enforced progress. Zhang Tian is a 62-year-old shopkeeper who has lived his whole life in the waterside town of Fengjie. The house where his children were born and his wife and parents died has now been demolished. While waiting more than a year for his promised new home, he has had to live in one of the hundreds of makeshift shacks that litter the wasteland around the reservoir.
Zhang is one of 1.2 million people who are being resettled. This number includes 70,000 farmers forced to relocate to alien provinces, although most have been offered housing in 13 new cities built higher up the Yangtze’s banks.
These new settlements are small cities consisting of mostly residential and retail units with a few leisure buildings and the odd office or hotel district. The tall residential towers look like they’ve been picked out of a catalogue – all pastel-coloured and unsubtle pastiche in style. Although they are quite ugly, their slick newness holds some promise for people who’ve never had it so good.
Billboards scattered about the new development claim that masterplanning has been central to the project, but the public squares and street layouts look as though they were dreamed up in an office without too much public consultation or too many site visits. The size of each new development varies according to how much the old town had spread above the new water level. Cities that will soon be underwater have been completely rebuilt on higher ground, and elsewhere there are unhappy marriages of new and old.
Zhang says the new buildings at Fengjie are “beautiful” – and though clearly an improvement on the grim concrete settlements built for Mao Tse-tung’s proletariat, the ice cream-coloured towers are hardly models of architectural integrity.
The Yangtze’s new cities exemplify the thinking that dominates current architecture in China – a thinking that reflects a bizarre 21st-century brand of Communism. Just as statues of Mao face off against billboards of basketball stars, so in the model cities there is a yearning for all things American. Each one has a Disneyland-style church, while prime sites have been taken by mock-classical shopping malls. Accommodation is in four- and five-storey apartment blocks arranged around schools and community facilities. Yet the Chinese government says the people are happy with the dam, and according to project official Luo Yuanhua, the cities are “well planned and modern – half-a-century ahead”.
Less well planned has been the distribution of compensation to make up for the loss of livelihoods. The amounts range from £1200-2400, but extracting such sums from officials with sticky fingers has proved difficult for many. In 2000 there were riots near Chongqing, the municipality at the western edge of the reservoir, which has a population of 31 million people. Last year a group of short-changed farmers made the long march to Beijing to present their case. And more could follow after a government audit declared £30m of resettlement funds unaccounted for.
Such controversy has dogged the Three Gorges Dam since its inception. In China the scheme has prompted outspoken criticism, with the National Congress’ initial debate recording the largest ever number of “no” votes against a government policy. But the Chinese government is adamant that the completed scheme will show the world the muscles of a nascent superpower. This weekend, Sunday 15 June – when the water level will reach its new temporary level – will be marked with fireworks and back-slapping, as the idea mooted by Sun Yatsen, father of the modern Chinese state, in 1919 and later endorsed by Mao is finally realised. It will be a symbol of what China can do – crucial at a time when the Sars epidemic has made the country a leper in the eyes of the Western world, and as it gears up to host the Olympics in 2008.
A symbol, that is, if everything works. The process of flooding the newly constructed dam is the period of the highest risk. While the stragglers scramble up the riverside out of the water’s reach, the government has issued an urgent warning that this summer’s rainy season will be severe. Normally, the Yangtze flows at 14,300 m3/s (by contrast, the river Thames in London flows at 66 m3/s), but in flood that figure can rise as high as 98,000 m3/s. It is predicted that the influence of El Niño will swell the Yangtze’s middle and lower reaches, where the dam is located. If the dam cracks, collapses or overflows, millions of lives will be threatened.
“We must prepare for possible deluges and consider the situation as seriously as possible,” says Luo Qingquan, director of the Special Anti-Flood Commission and governor of Hubei Province. He has urged the speeding up of emergency preventative measures and said vigilance is needed to face “the fierce challenges”.
At the same time geological experts have warned that the extra water could cause massive landslides along the banks and even a localised earthquake. These fears are compounded by China’s past record of civil engineering disasters. During the construction of the dam it was revealed – after being kept secret for 20 years – that when two dams in Henan Province collapsed in 1975, as many as 230,000 people were killed. A similar accident on the Yangtze today would mean the 3 million people of nearby Yichang would be dead in less than an hour.
If the Three Gorges Dam has always been about man pitted against nature, this month will surely decide the winner.
Rising tide: The momentum behind the Three Gorges project
1919 Sun Yatsen proposes a dam at the Three Gorges.
1953 Mao Tse-tung urges that a dam be built at the Three Gorges to control flooding.
1984 Feasibility report on the Three Gorges Water Control Project.
1992 A preliminary plan is given the go-ahead.
1994 Construction begins.
1996 Two major infrastructure projects, the Xiling Bridge across the Yangtze and an airport in Yichang city are completed.
1997 The first wave of residents in the reservoir region are relocated.
1997 A 3.5 km diversion canal is opened on the Yangtze’s southern bank. This is followed by the blocking of the main channel and drying out of the riverbed where construction of the main dam begins.
1997 Work on 13 new towns and connecting infrastructure begins.
June 2003 The finished dam closes and in two weeks the reservoir area rises 135 m.
Highlights of the dam’s construction
- Mixing and pouring 27.15 million m3 of cement
- Erecting 281,000 tons of metal structures
- Making and erecting 354,000 tons of reinforcing bars
- Building 231,000 m2 of leak-proof concrete walls
- Installing power generators with a combined capacity of 18.2 million kW
- Shifting 180 million m3 of stone and earth
The dam has been constructed across the Xi Ling gorge, the furthest downstream of the three gorges, where a hard granite boss cuts through the softer limestone geology to provide a solid base for it. Because the river is wider at this point, it provided the opportunity for the dam’s engineers to divert the river during the dam’s construction. In engineer-speak, the dam is a “gravity construction”, which means it is prevented by its own weight from overturning. When construction is complete in 2009, it will stand 181 m high and stretch more than 2300 m in length. It has been designed so that on its crest, 22 gated openings will act as overflow outlets to prevent the water flowing over the dam. There are also openings in its face: 90 m above the foundations are a row of 23 gates, which will be used to lower the water level during the flood season, thereby preventing upstream flooding. Further down the dam face there are another 22 openings, used to control the water level behind the dam during its construction. These will be blocked when construction is complete. Two powerhouses at the toe of the dam will contain the turbines to generate 18,200 MW of power – which is about one-third of the UK’s power demand. To allow boats to continue to use the Yangtze, a massive shiplock is being constructed on the left bank. This two-lane, five-step lock will lift or lower vessels 113 m. To construct this, more than 40 million m3 of rock has had to be removed, chiselled from the gorge. There are three main phases to the dam’s construction, all of which involved diverting the river. First, a diversion channel was constructed adjacent to the right bank. Rocks were dumped into the river to create a cofferdam to seal off a section of the river. Water was pumped out from behind the enclosure to create a dry pit, which was excavated to form a deep channel. The second stage involved the construction of two rock-filled cofferdams across part of the river, one upstream, one downstream of the dam’s site, connected to the left bank. At this stage in construction, 194,000 m3 of rock were dumped a day. The river was then diverted through the newly constructed channel. Meanwhile, inside the cofferdams, construction of the dam commenced. Nine concrete batching plants with a total capacity of 2,400 m3/hour were used. The concrete was mixed with aggregates excavated downstream of the site. The concrete must be placed at a temperature of between 12-14°C, if it is to retain sufficient strength. Before the aggregates are mixed with the cement they are cooled to –5°C and ice is used in the mixing water to produce concrete at 7°C. With the outside temperature rising as high as 40°C in summer, the concrete is whisked to site by conveyors. Cooling water pipes within the concrete help to limit temperature rises, while insulation is used to prevent the rapid cooling of the external surfaces at night. Earlier this month the final diversion took place. With the main section of the dam now complete, the two giant cofferdams were removed, and a new one constructed to block off the diversion channel. The final section of the dam wall will now be built behind the cofferdam adjacent to the right bank. With the new dam in position, water has started to back up behind the dam, flooding the gorges, until it reaches the temporary low-level sluices 54 m above the foot of the dam. Construction is programmed for completion in 2009, by which time the water level will have risen to 175 m.
Submerged: The facts and figures
- The project is said to cost £12bn, although total investment is likely to be higher – some sources suggest as much as £30bn.
- The main dam is 185 m high and 2 km wide. There are 3500 km of additional fortified embankments.
- The dam will supply one-fifth of China’s electricity – the equivalent of 18 nuclear power stations. Power generation will commence in August with more generators added until final completion in 2009.
- Between 1 and 15 June, the Yangtze will rise 135 m. The level will reach a maximum height of 175 m by 2009.
- The 480 km long reservoir holds 22.15 billion m3 of water.
- Up to 1.2 million people have been rehoused or given compensation packages of £1200-2400 according to the government. Other sources suggest as many as 2 million people have been displaced.
- Thirteen new cities replace dynamited habitations.
- In Chongqing Province, officials have closed 567 stone quarries and 12 large factories in an attempt to reduce population. They have expressed a willingness to close 956 industrial enterprises in total.
- More than 8000 important archaeological sites are now submerged.
- The dam will disturb the natural habitat of hundreds of endangered species, including the Yangtze river dolphin, Chinese alligator and Siberian crane.
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