When was three gorges dam constructed




















Besides, the dam can only hold back the water for so long, as it has to make room for new rains -- and in flood season torrential downpours can come in quick succession. Last month, three flood waves have already hit the Three Gorges.

The dam has opened its sluice gates multiple times since late June to release water from its reservoir, drawing criticism on Chinese social media that this exacerbated the floods downstream.

The company running the dam denied this, telling state-run tabloid the Global Times that it had helped to delay and stagger the floodwaters reaching downstream.

But Poyang Lake, in Jiangxi province, still swelled to its highest level in history -- surpassing the previous record set by catastrophic floods in , which killed more than 3, people. Other places downstream also broke historical records. This aerial photo, taken on July 15, , shows a flooded area near Poyang Lake due to torrential rains in Poyang county, Shangrao city in China's central Jiangxi province. David Shankman, an emeritus professor of geography at the University of Alabama, who has studied flooding on the middle Yangtze, said the record-breaking water levels showed that the Three Gorges Dam could not prevent severe floods.

Studies by Chinese and foreign researchers over the years, Shankman added, have found that the dam's reservoir is too small to significantly reduce downstream discharge during severe floods, although it does help alleviate flooding during normal years.

Miroslav Marence, an associate professor of storage and hydropower at the IHE Delft Institute for Water Education, said the problem is not the design of the dam, but the expectation that the dam can solve all the problems of flooding on the Yangtze, the third largest river by volume in the world. 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 World's Largest Hydropower Plant Upon completion, the Three Gorges Project will be the world's biggest hydropower plant in terms of both total installed capacity and annual average power generation volume.

Twenty-six turbine generator sets, with a per-unit generation capacity of , kilowatts, will be installed on the left and right banks of the Three Gorges Hydropower Station.

The overall generation capacity is estimated at The annual power generation is estimated to average The Three Gorges Hydropower Station will be hooked up with thermal power and hydroelectric grids in central and eastern China, thus improving the economy and reliability of the electric grids. Moreover, China has mapped out state energy strategies by transporting coal resources in northern China to the southern regions and transmitting electricity generated from the western parts to eastern localities in a bid to ease the energy shortage in central and eastern China.

Three Gorges Project to Take 17 Years The ongoing Three Gorges Project, which will be the world's largest water conservation facility when completed, will take 17 years to build. Construction of the project consists of three stages.

The preparatory and first-phase projects spans five years from , whose completion is signaled by the damming of the Yangtze River on November 8. The second phase will run from to This phase will be completed when the first generating unit in the left-bank power plant goes on line and the permanent ship lock begins operation.

The third phase is planned for Landscape and Cultural Heritage: After the impoundment of the reservoir, higher water level and wider channel would change the scenery of the canyon to a certain extent' The elevations of mountains and peaks along the banks in the gorges range from to 1, m in nature. The elevations of the famous 12 peaks in Wuxi a Gorge are around 1, m. The most reputed Goddess Peak is more than m above sea level. The normal pool level of the reservoir at m will result in an increase of 40 to m higher in the Gorges than at present.

So the steep canyon enclosing the river valley will be basically untouched, even though the rapids and dangerous shoals will be eliminated. Better navigation condition will provide access to new scenic views, for instance, the Lesser Three Gorges " along the Daning River' The magnificent Three Gorges Project shall certainly become a new hot spot of tourism.

Environment : Dam defenders point to the environmental benefits given by the dam, such as the availability of hydroelectric power, which is much cleaner than the coal burning China has relied heavily for decades. They believe the dam will reduce greenhouse gas emissions by reducing coal burning thereby protecting the ozone layer and have none of the radiation hazards at nuclear plants.

The world's largest water conservancy project with the biggest flood-control capability. The total storage capacity of the reservoir is The total installed capacity of the Three Gorges Hydropower Station is 18, MW with an annual electricity output of The world's largest water conservancy project with the world's largest project building scale. The total length of the dam axis is The spillway section, which is located in the middle of the river course,is meters long in total.

There are 26 sets of turbine generator units in total, MW for each. The shiplock is schemed out as a double-way and five-step lock. It is the world's largest water conservancy project with the world's largest project building scale. If passengers want to experience how the ship cross the dam, take the optional tour of ship lock experience is a good choice. The ship lift an optional tour of Yangtze River Cruises.

On both upstream day 2 and downstream day 4 , passengers will disembark, and take a specially-designed sightseeing boat through the ship lock lift. A visit to the Three Gorges Dam will follow. Then the cruise companies provide land transfers between Yichang and Maoping in both directions for embarking and disembarking passengers.

Under construction since and completed last November, the ship lock lift is the final component in the Three Gorges Dam complex. It is the largest of its kind in the world, capable of lifting ships of up to 3, tons. It is nearly the height of a story building, with a water volume equivalent to 4 Olympic swimming pools. The Three Gorges Project has its main benefits in flood control, power generation and navigation. Historically, the population in the middle and lower reaches of the Yangtze River suffered tremendous losses from flooding both in human lives and property.

In alone, as a result of flooding, thousand hectares of cultivated land were stricken, thousand people were drowned. Currently, 15 million people and 1. Once the project? Thirdly, the project will enable 10,ton towboats to sail up-stream as far as Chongqing.

The Yangtze? Problems to Be Resolved The project also presents daunting problems which should be properly handled and solved to avoid any possible undesired impacts. These include resettlement of population, environmental protection, fund raising, etc.

About 1 million people will be relocated owing to the construction of the project. The government has attached great importance to the issue and decided to appropriate large sums of money for the resettlement program.



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