For example, while the Three Gorges Dam can reduce the intensity of floods coming from upstream to a certain extent, it won't be able to prevent floods caused by intense rainfall on the middle and lower reaches of the Yangtze or the tributaries in its basin entirely, he added. And that is part of the problem: A lot of the flooding in central and southern China this summer, for instance, was caused by rains that fell downstream and didn't ever go through the dam.
The dream of every Chinese leader. The Chinese have for millennia manipulated waterways for flood control, irrigation and navigation. For China's imperial rulers, the ability to harness rivers not only saved lives and brought prosperity, but also gave legitimacy to their reign, as natural disasters were taken as a sign that the emperor had lost the mandate of heaven, by which he ruled. This ambition to control water resources has only grown in modern times, with the prowess of technology.
Every Chinese leader since Sun Yat-sen, the founding father of modern China, dreamed of building a massive dam on the Yangtze, which has repeatedly wreaked havoc on its banks during flood season.
In an industrial blueprint he laid out for the Republic of China in , Sun envisioned damming the Three Gorges to improve navigation and provide hydropower for the whole country. The revolutionary leader did not live to see this dream realized. His successor Chiang Kai-shek carried on with the task in the s, inviting renowned American engineer John L.
Savage -- best known for his work on the Hoover Dam -- to survey the valleys and draw up a design for the Three Gorges Dam. Chiang even sent dozens of Chinese engineers to the US for training, but the project was abandoned during the Chinese Civil War. After the Chinese Communist Party took power, Chairman Mao Zedong endorsed the project, writing about "walls of stone" and "a smooth lake rising in the narrow gorges" in a poem.
When his successor Deng Xiaoping brought up the idea again in the late s, it was strongly opposed by some leading hydrologists, intellectuals and environmentalists, who pointed to its human and environmental costs, from the mass relocation of residents to threats of geological hazards, environmental damage and loss of archeological sites.
It was heavily debated throughout the next decade, which was the most politically relaxed and liberal era in the history of Chinese Communist rule. But following the Tiananmen Square massacre in , open dissent was stifled and the political atmosphere turned oppressive.
Four months after the massacre, authorities banned " Yangtze! Confident that it could now push through the plan, the government put the dam to a vote before the country's legislature, the National People's Congress NPC , in The dam was approved, but about one-third of the delegates refused to endorse the plan -- an astonishingly low approval rate for China's usually compliant rubber-stamp parliament. Some delegates said they were blindsided when the Three Gorges Dam suddenly appeared on the NPC's agenda, without advance notice or discussions about the project, according to a edition of "Yangtze!
Yang Xinren, a delegate from Jilin province in northeastern China, was quoted by the book as saying : "The majority of the delegates are not fully informed of the technical aspects of the project. So no matter how we vote, we vote in blindness. Why is the dam so controversial? One of the most controversial aspects of the mega-project was its enormous cost for villagers who had lived for centuries on the banks of the river.
To make way for the dam's massive reservoir, about 1. Building the Three Gorges Dam displaced more people than the three largest Chinese dams before it combined.
The reservoir submerged two cities, towns and 1, villages along the river banks. Residents of Fengjie, in southwest China's Chongqing, watch the demolition of buildings in their town on November 4, , to make room for the Three Gorges Dam's resevoir. Displaced residents have complained about inadequate compensation and a lack of farmland and jobs after relocation. Many have accused local governments of embezzling resettlement funds and using excessive force to quell protests.
In , the Chinese government acknowledged that some of the funds were embezzled or misused. Many also faced a reduction in living wages. The dam has also had a serious geological impact. Chinese officials and experts admitted at a forum in that the Three Gorges Dam had caused an array of ecological ills, including more frequent landslides, China's state news agency Xinhua reported at the time. The water in the reservoir saturates and erodes the base of the cliffs, and the fluctuation in water levels changes the weight of the reservoir and the pressure on the slopes, destabilizing the shoreline, geologists say.
Water gushes out for the first time through the Three Gorges Dam on June 11, The first disaster came in , shortly after the reservoir started to fill for the first time. As the water reached meters feet , landslides began to occur. Among their concerns: landslides caused by increased pressure on the surrounding land, a rise in waterborne disease , and a decline in biodiversity. But their words fell on deaf ears. Harnessing the power of the Yangtze has been a goal since Nationalist leader Sun Yat-sen first proposed the idea in Mao Zedong, the father of China's communist revolution, rhapsodized the dam in a poem.
The mega- project could not be realized in his lifetime, however, because the country's resources were exhausted by the economic failures of the Great Leap Forward in the late s and then the social upheaval of the Cultural Revolution from the mids a to the early s.
Four decades later, the government resuscitated Mao's plans. The first of the Yangtze's famed gorges—a collection of steep bluffs at a bend in the river—was determined to be the perfect site. In June , nine years after construction began, the state-owned China Yangtze Three Gorges Development Corporation CTGPC filled the reservoir with feet meters of water, the first of three increments in achieving the eventual depth of feet meters.
The result is a narrow lake miles kilometers long—60 miles 97 kilometers longer than Lake Superior—and 3, feet 1, meters wide, twice the width of the natural river channel. Scientists' early warnings came true just a month later, when around million cubic feet 20 million cubic meters of rock slid into the Qinggan River, just two miles three kilometers from where it flows into the Yangtze, spawning foot meter waves that claimed the lives of 14 people.
Despite the devastating results, the corporation three years later in September raised the water level further—to feet meters. Since then, the area has experienced a series of problems, including dozens of landslides along one mile kilometer stretch of riverbank. This past November, the ground gave out near the entrance to a railway tunnel in Badong County, near a tributary to the Three Gorges reservoir; 4, cubic yards 3, cubic meters of earth and rock tumbled onto a highway.
The landslide buried a bus, killing at least 30 people. Fan Xiao, a geologist at the Bureau of Geological Exploration and Exploitation of Mineral Resources in Sichuan province, near several Yangtze tributaries, says the landslides are directly linked to filling the reservoir. Water first seeps into the loose soil at the base of the area's rocky cliffs, destabilizing the land and making it prone to slides. Then the reservoir water level fluctuates—engineers partially drain the reservoir in summer to accommodate flood waters and raise it again at the end of flood season to generate power—and the abrupt change in water pressure further disturbs the land.
That is apparently what happened to the 99 villagers of Miaohe, 10 miles 17 kilometers upstream of the Yangtze, who saw the land behind their homes split into a foot- meter- wide crack last year, soon after the reservoir water level was lowered for the summer floods. Officials evacuated them to a mountain tunnel where they camped for three months.
One of the greatest fears is that the dam may trigger severe earthquakes, because the reservoir sits on two major faults: the Jiuwanxi and the Zigui—Badong.
According to Fan, changing the water level strains them. Many scientists believe this link between temblors and dams—called reservoir-induced seismicity—may have been what happened at California's Oroville Dam, in the foothills of the Sierra Nevada.
The largest earthen dam in the U. Seven years later, when the reservoir's water supply was restored to full capacity—after engineers lowered it feet 40 meters for maintenance—the area experienced an unusual series of earthquakes. Geological Survey seismologists subsequently found a strong link between the quakes and the refilling of the reservoir.
The Oroville area was sparsely populated, so little damage was done. But earthquakes have also been connected to past hydropower projects in China, where dams are often located in densely populated and seismically active river basins. Engineers in China blame dams for at least 19 earthquakes over the past five decades, ranging from small tremors to one near Guangdong province's Xinfengjiang Dam in that registered magnitude 6. Surveys show that the Three Gorges region may be next.
So far, none have been severe enough to cause serious damage. But by , the dam's water level is set to be raised to its full foot capacity and then lowered about feet 30 meters during flood season. That increase in water pressure, in water fluctuation and in land covered by the reservoir, Fan says, makes for a "very large possibility" that the situation will worsen.
Local news media report that whole villages of people relocated to make room for the dam will have to move a second time because of the landslides and tremors, indicating that officials failed to foresee the full magnitude of the dam's effects. Guangzhou's Southern Weekend late last year reported that villagers in Kaixian County were eager to move again, citing landslides, mudslides and ominous cracks that had appeared in the ground behind their homes.
They also hoped that moving might resolve land allocation issues: Some said they received only half of the acreage they had been promised. Water Displacement The dam is also taking a toll on China's animals and plants. The nation—which sprawls 3. The Three Gorges area alone accounts for 20 percent of Chinese seed plants—more than 6, species.
Shennongjia, a nature reserve near the dam in Hubei province, is so undisturbed that it is famous for sightings of yeren, or "wild man"—the Chinese equivalent of "Big Foot"—as well as the only slightly more prosaic white monkey. That biodiversity is threatened as the dam floods some habitats, reduces water flow to others, and alters weather patterns. Economic development has spurred deforestation and pollution in surrounding provinces in central China, endangering at least 57 plant species, including the Chinese dove tree and the dawn redwood.
By , China had a total of 23, large dams. More countries recognised the environmental impacts did not surpass the cheap renewable energy that they provided. However, climate change is predicted to bring more frequent and heavier flooding. Meaning China will have no choice but to look towards other solutions in the future. The first in a series of ecological disasters happened in when the dam was filled for the first time. It was when the water reached feet meters that the landslides started to happen.
Only a matter of weeks after this, a large chunk of mountainside slid into the river. The result was 24 lives lost, houses destroyed and 20 capsized boats. Over plant species, insect species and fish species exist within the environment surrounding the dam. The Three Gorges Dam not only has directly impacted these species, but also the environment they exist in. For example, aquatic ecosystems have been negatively affected by a lack of dissolved oxygen in the water. The dam disrupts the natural process of aeration and diffusion.
The Baiji dolphin species that lived in the Yangtze river for over 20 million years was declared extinct in It has not been declared as a sole direct result of the Three Gorges Dam, but its demise was put down to wide-scale habitat destruction and pollution.
The building of the dam further reduced its habitat and the resulting increase in ship traffic are thought to be contributing factors to their extinction. Not only has the Baiji dolphin been affected, but many animals and plants have had their habitats severely damaged or completely destroyed. It has been estimated that the Three Gorges Dam threatens over plant species.
The Three Gorges Dam sits on two fault lines and geologists have warned of reservoir-induced seismicity. This is caused by the rapid change in water pressure when the reservoir water levels are changed during flood season.
The result is the activation of already shaky ground and this triggers an earthquake. The dam has been directly blamed for the increase of earthquakes in the region. The technological accomplishment of the Three Gorges Dam became a blazing point of national pride for China. Chinese rulers for centuries have harnessed the power of rivers to give their reign legitimacy.
If a ruler is able to prevent natural disasters, they are considered to have secured their mandate with the heavens. And following the political oppression within China following the Tiananmen Square massacre, top environmentalists were jailed. Along with the banning of books that criticised the Three Gorges Dam project.
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