DAMNED: THE ENVIRONMENTAL CONSEQUENCES

OF CHINA’S THREE GORGES PROJECT

 

In 1912, Chinese revolutionary leader Sun Yat-sen first suggested damming the section of the Yangtze River known as the Three Gorges.  Almost 40 years later, the father of Communist China, Mao Tse-tung wrote a poem that fantasized about “walls of stone” that would hold back “clouds and rain till a smooth lake rises in the narrow gorges,” (Watkins 1997).  Finally, in 1992, a plan was approved that would make the Three Gorges the site of the world’s largest dam—more than 600 feet high and 1.3 miles wide, with a reservoir a mile wide and 370 miles long.  It’s purpose, according to the Chinese government, will be to control flooding on the Yangtze River, generate electricity, and allow improved navigation all the way inland to Chongqing, but the dam won’t come at a small price.  Current estimates predict that by the dam’s completion in 2009, the Three Gorges Project (TGP) will cost China anywhere between $34 billion and $75 billion (Qing 1998).  The greatest cost, however, may not be entirely known until years after the dam is completed and the cost of the environmental devastation it will cause can be evaluated.

The third-longest river in the world, the Yangtze winds through central China, crossing most of the country until it reaches its mouth in the Yellow Sea.  Since the earliest dynasties, the river has inspired artists and poets to create some of China’s greatest works.  Earlier civilizations that lived along the river built temples and monasteries in the misty mountainous gorges where they lived a simple agricultural lifestyle, taking only what they needed to live from the river.  Now, with the construction of the Three Gorges Dam, neither residents of the area nor visitors will be able to enjoy the area’s natural beauty while walking along a steep footpath to a temple built thousands of years ago out of respect for the river.  Instead, much of the Three Gorges region will be underwater, with a huge steel and concrete eyesore at one end of the reservoir.  Unfortunately, however, the environmental consequences of the TGP are much worse than simply the destruction of a place of great beauty.

The TGP will have a wide-range of serious consequences, the most significant of which are the social consequences that come with relocating nearly two million people; however, at their most basic level, these consequences are a direct result of environmental issues.  If building the dam alone does not come at enough of an environmental cost, add to it the cost of environmental degradation after people from 19 cities, 326 towns, and hundreds more small villages move onto land that in many places is already environmentally strained (Qing 1998).  Although the Yangtze is only the third longest river in the world (3,700 miles long), no other river affects as many lives.  Approximately one third of China’s population (about 380 million people) live along its banks, and half of China’s food is grown there (Qing 1998).  In some villages, residents rely completely on the river for their way of life.  They wash, bathe, fish, and irrigate their crops with water from the river.  These people will have to drastically change their lifestyles and alter traditions that have been passed on from generation to generation when they are moved to make room for the dam, and they will have to do so using less land that is not nearly as fertile as the area from which they were moved. 

            Prior to any construction and resettlement, about 40% of the mountainous land in the Three Gorges region was already under cultivation.  A large portion of the remaining land is found on slopes with a 25% or greater gradient and cannot be farmed under the Water and Soil Protection Act (Qing 1998).  When resettlement was first considered, the plan was based on an estimate of 750,000 people who were to be relocated to 3,680,000 mu of land (15 mu equal one hectare).  However, due to the terrain and the laws governing land use, most recent findings show that only about 800,000 mu can actually be used, and even that number may be high (Qing 1998).  Confounding the problem is the fact that the actual number of people that will be relocated by the end of the project is approaching two million, meaning that with more people and less land than expected, it will be impossible to adequately compensate families who will be relocated (Qing 1998).  The mountainous land that these people will likely be moved to will also produce lower crop yields, meaning families will have to make a living on less land that is of poorer quality than the land they came from. 

The only solution, it seems, is one that has already been put into practice at some trial resettlement sites: using protected land for farming.  This requires cutting into what is left of forested land in the region, despite the fact that the forest cover before construction began was already about half of what it was in the 1950’s.  As a result, there will be a drastic increase in soil erosion (already a problem in more than 50% of the region before construction began), which will add to an already bad sedimentation problem that could compromise the dams ability to prevent flooding (Qing 1998).

The Yangtze currently has one of the highest silt contents of any river in the world, with, on average, about 680 million tons of silt flowing through the river each year and much more that is left on its banks on the way (Salazar 2000).  The silt content has increase dramatically in recent years as a result of decades of unregulated industrial development as well as poor agricultural practices that grew out of Mao Tse-tung’s “grain first” policy.  This increase in sedimentation has led to severe flooding problems, such as the floods of 1998 that were some of the worst China experienced in 40 years (Salazar 2000).  With the dam completed, much of the silt that was once washed away by the natural course of the river will collect behind the dam, possibly causing the dam to do the exact opposite of what the Chinese government hopes it will do in alleviating flooding.  Flooding brings more of its own environmental consequences, such as even more erosion, disease, and the possibility of blocking outlets for sewage that might then collect in upstream cities such as Chongqing (Salazar 2000). 

Considering all these factors—large numbers of people with a swiftly growing population, little arable land, deforestation, and erosion—it won’t be long until the resource base in the Three Gorges area is either washed away in a flood or completely exhausted, a problem that will have serious repercussions around the country as well as the world. 

An additional environmental problem that comes as a result of having a large number of people in a small space is pollution.  Chinese officials claim that the dam will actually help China’s current environmental state by providing 18,000 megawatts of hydropower each year, equivalent to 10% of China’s energy needs (Salazar 2000).  While this may be true, water pollution as a result of the dam will only get worse.  Currently, about 3000 factories and mines discharge barely-treated wastewater into the Yangtze, and many residents that live along its banks also use the river to dispose of waste (Qing 1998).  While scientists acknowledge that waterways have some natural ability to cleanse themselves (through its natural course and flooding, most of the pollution is flushed out of the Yangtze), they believe that the dam will interfere with this process, causing over one billion tons of industrial and human wastes to flow into the reservoir where it will collect behind the dam (Salazar 2000).  In addition significant amounts of toxic waste, including mercury and arsenic, from China’s industries have accumulated in pits and crevasses in the gorges.  As the reservoir is filled, more than 300 factories will be submerged and these and other toxins will enter the water since no money has been set aside to clean up the sites before they are inundated (Qing 1998 and Salazar 2000).  Many of these toxins will also remain stuck behind the dam instead of being flushed out by the river’s natural course, adding to the pollution problems that already exist. 

            People aren’t the only ones who will be forced from their homes and threatened by pollution due to the TGP.  Construction of the dam also threatens several endangered species native only to the Yangtze River, including the Whitefin Dolphin and the Chinese Sturgeon (Topping 1998 and Salazar 2000).  The Chinese Sturgeon has flourished in the Yangtze for 140 million years, making it one of Earth’s few “living fossils.”  It grows to be 12-14 feet long and can live for hundreds of years.  This unusual fish has been the source of countless Chinese legends and fables but has been threatened since the first phase of dam construction severed the path to the its spawning grounds (Topping 1998).  The Whitefin dolphin is the largest freshwater dolphin in the world (300-500 lbs.).  It has been legendary in China for centuries, but today there are fewer than 100 still living (Salazar 2000).  Even before the dam, pollution was a problem for the dolphins; now the ecosystem has been irrevocably upset.  By the time the dam is complete, the dolphins may be gone for good, since attempts at preservation programs have so far been unsuccessful (Topping 1998).  The dam will also threaten the Chinese Alligator, the Finless Porpoise, and the White Crane as well as many different fish species and some types of monkeys that live in nearby limestone cliffs (Topping 1998).

Although most of the environmental damage caused by the TGP will occur in the Three Gorges region, the project also has the potential to cause serious consequences outside of China.  Last April, Florida State University oceanographer Doron Nof published an analysis of the project in the Bulletin of the American Morological Society in which he asserts that the dam may cause air temperature warming of several degrees Celsius in Japan (Perkins 2001).  The dam will impound more than 10 trillion gallons of water in the Three Gorges region that may be used for irrigation, preventing the Yangtze from dumping its usual eight million gallons of fresh water per second into the Yellow Sea.  According to Nof, this water, which is carried northward by ocean currents to the Japan Sea, helps to create an insulating blanket that keeps heat from the water below from entering the atmosphere through convection.  He says that if China diverts as little as 10% of the Yangtze’s water, it would be enough to prevent the insulating layer from forming, bringing warmer temperatures and all of the associated problems to Japan (Perkins 2001). 

            If all of these ecological costs are not enough to outweigh the benefits of carrying the TGP to completion, one needs only consider the possibility that the dam may not function as planned.  In the best case scenario, the engineers of the project will probably have to figure out how to deal with sedimentation problems and flooding; in the worst case scenario, the dam could collapse and cause a catastrophe with unfathomable consequences (Qing 1998). 

            For the TGP to work, engineers have designed the dam and reservoir so that over time, sedimentation is supposed to build up to a certain level and then reach equilibrium in the reservoir, after which the usual annual sediment load will pass through the dam.  The predicted time for the dam to reach this equilibrium, however, is not until 70-150 years after it begins functioning, and studies of every large dam in the U.S. and China (most of which are still much smaller than the Three Gorges Dam) have shown that predictions for sediment accumulation beyond 50 years are almost never accurate (Qing 1998).  If this is the case for the TGP, as it likely is due to the uncertainty of the effects of resettlement on erosion and sedimentation, the resulting problems will be magnified proportionally to the dam’s size.  Also considering the fact that the design for the dam pushes the limits of engineering and is completely untested, the possibility of problems due to excess sedimentation is very likely.  The most likely effects would be on dams downstream, including the Gezhouba Dam which has already shown signs of structural deterioration despite being completed just 14 years ago and would therefore be more prone to collapse under intense water pressure from upstream (Qing 1998). 

            A team of U.S. scientists who visited the Three Gorges site in 1997 have predicted similar problems to those found at the Gezhouba Dam for the Three Gorges Dam, which would only make existing problems even worse.  The scientists found deviations from standard procedures, overestimations of rock strength beneath the dam, and unconventional designs in the coffer dam construction, all of which could lead to seepage around and beneath the dam or entire dam failure (IRN 1999). 

            In addition to the engineering challenges that the project faces, the dam also faces the natural challenge of its reservoir being situated above an active fault line.  Although the dam’s advocates assert that it is engineered to withstand a large seismic shock, seismologists worry that unless the dam is designed flawlessly (which is not likely, based on other observations and China’s history of dam building), there is a possibility that the weight of the water in the reservoir could trigger a serious earthquake (Topping 1995).  Another possibility is that heavy rains could simply overtake the dam’s design and cause it to wash out.  Yet a third possibility is that heavy rains or seismic activity could cause a large cliff face upstream to break off and fall into the river, causing waves as high as 250 feet and severely damaging the dam.  Any of these situations—which are entirely beyond the control of any engineering solutions—could cause flooding that would threaten the lives of 75 million Chinese downstream and bring environmental consequences that are too large to even predict (Salazar 2000).   

            The construction of the Three Gorges Dam will likely have environmental consequences that far exceed any benefits that can be gained from its construction, so it seems unreasonable that project has been allowed to continue.  Sadly, the reason that it has is the same as it is for many other projects that have large-scale environmental consequences—politics.  Historically, China’s dam building projects have been political schemes to attempt to demonstrate the power of socialism and the TGP is no exception.  Government corruption has allowed for incomplete cost-benefit analyses and the skewing of results of studies to favor the dam’s construction, and China’s socialist regime has severely punished those who dare to speak out against the project (Qing 1998).  With so much governmental pride invested in the project, even the most convincing evidence from researchers of the consequences China will face as a result of the dam has proven to have little effect. 

            The cost of the Three Gorges Project has been staggering so far, but it will only continue to increase exponentially as the consequences add up.  The problems of relocation, deforestation, sedimentation, flooding, the loss of endangered species, and the possibility of failure could be damaging enough on their own, but the Three Gorges Project opens the possibility for the combination of more than one—and possibly all—of these problems.  The last hope for the Three Gorges may be a large-scale uprising of the people with help from conservation and river protection organizations around the world.  Even with that, much of the damage has already been done since construction began in 1994.  It may be that all we can do at this point is hope for the best in regards to the dam’s construction and performance and begin making plans to try to limit the environmental impact it will have.  Or we can simply watch and wait until the Yangtze itself rises up against the dam, proving that no human influence, not even the powers of socialism, can tame nature. 

 

WORKS CITED

Perkins, Sid. “Big Dam Project in China May Warm Japan.” Science News. 21 April 2001.

 

Qing, Dai.  The River Dragon Has Come!  The Three Gorges Dam and the Fate of China’s Yangtze River and Its People.  Ed. John G. Thibodeau and Philip B. Williams, Trans. Yi Meng.  New York: M.E. Sharpe, 1998.

 

Salazar, Joanna Gail.  “Damming the Child of the Ocean: The Three Gorges Project.” Journal of Environment and Development.  June 2000: 160-174.

 

Topping, Audrey Ronning.  “Ecological Roulette: Damming the Yangtze.”  Foreign Affairs.  9 January 1995: 132-147.

 

Topping, Audrey Ronning.  “Yangtze’s Dolphins Threatened.”  Earth Times.  29 April 1998.  Online.  Available: http://www.enn.com/features/1998/04/042998/0429fea_21758.asp. 21 March 2002.

 

“Three Gorges Site Visit Report.”  International Rivers Network.  17-18 October 1997.  Online.  Available: http://www.irn.org/programs/threeg/sklar.html.  21 March 2002.

 

Watkins, Lindsay. “China’s Juggernaut: The Three Gorges Project.” Hershey High School.  1997