ABSTRACT: Fan Xiao, the respected Chinese geologist and environmentalist, recounts two visits he made to regions along the Yangtze River that have been irrevocably changed by the Three Gorges Dam project. In 2012 and 2013, which marked the 10-year anniversary of the dam’s operation, Fan explored its impact on the environment and the people living upstream, along its immense reservoir, including at his hometown of Chongqing. Water- ways have been disrupted due to siltation and the creation of sandbars; tributaries have become stagnant; water quality has drastically deteriorated due to pollution and other problems; dangerous landslides routinely alter the legendary Three Gorges scenery, which has become a shadow of its former grandeur. Fan also tells of the dam’s effects on the Author’s note: This article, based people living along the Yangtze and its tributaries. Ancient villages lie submerged under on my trips to the Three Gorges water, while the relocated communities have been handicapped; long-established patterns reservoir area in 2012 and 2013, was published, in part, in the 2014 January of agriculture have been erased and the tourism industry has not recovered, leaving the issue of Chinese National Geography. local citizens struggling to make do. N o v e m b e r 2 0 1 4 | P R O B E I N T E R N AT I O N A L E D I TO R S : M U L A N , PAT R I C K FA R R E LL , PAT R I C I A A DA M S INTRODUCTION Following the Central Government’s State Council approval of the most seriously silted section of the Three Gorges reservoir’s 60-km “Three Gorges Post-Project Plan” in May 2011—an expensive long tail section (the upstream river channel where it meets the remedial program to address widespread environmental, geolog- reservoir) because this is precisely where the water begins to slow ical and economic problems created by the construction of the down. Now in the Jiangbeizui area of urban Chongqing, so much silt Three Gorges Dam on the Yangtze River—the Chinese and foreign has accumulated along the banks that the watercourse has shifted media, once again, shone a spotlight on the world’s largest dam by as much as 80 meters. In the Liangtuo area, 5 km downstream project. This gigantic project, which dammed Asia’s longest river from Chaotianmen Port, silt has raised the Yangtze’s riverbed by 10 and the world’s third largest in terms of volume, has altered half meters since impoundment1 of the Three Gorges reservoir began. of China’s natural landscape and society. It is thus no wonder that the dam has received constant international attention. Chongqing, There is also currently a sandbar located at the mouth of the Jialing the major section of the Three Gorges reservoir area, has experi- River (where it enters the Yangtze), near to Jiangbeizui (downtown enced the most profound changes. Chongqing’s financial district). Experts who participated in the Three Gorges feasibility study in the 1980s were deeply concerned SEDIMENTATION IN THE RESERVOIR “A VERY about this eventuality. Their prediction is now gradually occurring. SERIOUS PROBLEM” Not far from the mouth of the Jialing, several dredging boats were I visited the Three Gorges reservoir area twice during the early operating in the Yangtze, though I was not sure if they were dredg- springs of 2012 and 2013. Chongqing was the final stop on my ing the waterway, or just digging sand for building materials. two visits. In 2013, water levels were dropping slowly and steadily so the reservoir could make room for the coming flood season’s Mr. Wen also mentioned two other places where siltation problems increased water flows. As a native of Chongqing, I was shocked are becoming serious: at the Lanniwan section of the Yangtze in by what I saw: large areas of deep sandbars had appeared in the Zhongxian County (about 250km downstream of urban Chongqing Chaotianmen and Jiangbeizui regions on the Yangtze’s north bank. and 350 km upstream of the dam), and at the section just in front Even more surprisingly, a massive dam had been created from of the dam. the gravel carried by the river flow, stretching like a huge dragon from the confluence of the Jialing (a tributary of the Yangtze) and Yangtze Rivers, all the way to the center of the Yangtze. Moreover, half of the road that originally led to a cement riverside pier was buried under sandbars, forcing the waterway to shift to the other side of the river. I was shocked. I have never seen anything like this in my life. As early as October 2010, Wen Guanghua, director of the Chongq- ing Waterway Bureau, warned that sediment deposited along Chongqing’s waterway was becoming a “very serious problem.” He The so-called Lanniwan is the channel on the north side of Huanghua Island (indicated pointed out that the stretch between urban Chongqing’s Chao- by the arrow), which divides the Yangtze River in two, located 8km downstream of Zhongxian Town (the capital of Zhongxian County) and about 250km downstream of ur- tianmen Port and upstream to Honghuaqi in Jiangjin City was the ban Chongqing and 350 km upstream of the dam. Source: Google Earth, April 10, 2013. 1Impoundment refers to the accumulation of water in a reservoir behind a dam. 2 I visited the Lanniwan area in March 2012. There, I discovered able to pass through the Three Gorges reservoir area. But since Huanghua Island, located 8 km downstream of Zhongxian, the impoundment, around 70% of this sediment flow becomes trapped county’s capital. It is the only island in the entire Three Gorges in the reservoir each year. While it is true that the absolute amount reservoir, and divides the Yangtze River in two, with the so-called of silt accumulating in the reservoir is less than originally expected, Lanniwan being the channel on the north side. According to data the sediment-deposition ratio is much higher than expected. More provided by the Chongqing Waterway Bureau, prior to 2003 the importantly, the deposition of silt is highly concentrated in specific water in the Lanniwan was deep enough for shipping, even in the areas, such as at the reservoir’s tail, at bends in the river, at the es- dry season. But based on data released by Chongqing Jiaotong tuaries of Yangtze tributaries, and immediately in front of the dam, University experts, a total siltation volume of 103 million tons all of which negatively impact the navigability of the waterway. flowed down the Yangtze from 2003 to 2010, resulting in a buildup of sediment in the Lanniwan that now exceeds 50 meters deep. In GEOLOGICAL DISASTERS: MORE FREQUENT WHILE May 2011, the bureau closed Lanniwan channel because the river FILLING THE RESERVOIR course had become completely blocked by silt. On last year’s trip to Chongqing, I also visited and interviewed ex- perts at the Chongqing Geological Environment Monitoring Station. Before impoundment of the Three Gorges Dam reservoir (i.e. They informed me that since the first trial to fill the reservoir to 175 before the sluice gates were closed), the annual sediment flow into meters or its NPL (Normal Pool Level) began in September 2008, the reservoir from upstream of the Yangtze and its tributaries was the routine rising and falling of water has triggered numerous about 460 million tons, while the annual sediment yield discharged geological disasters, including earthquakes and landslides. As of from the reservoir area to the lower Yangtze, downstream of July 2011, at least 272 geological disasters and imminent disasters Yichang (a city approximately 40 km downstream of the dam), was (such as precariously situated rock masses) have been documented about 523 million tons. In other words, before impoundment, the in the Chongqing region of the reservoir area. These incidents were dynamic of sediment flows was stable. In geomorphic terms, there highly concentrated in the years 2008 and 2009, especially during was little or no accretion (buildup) of sediment. Before the dam the periods when the reservoir was being filled and lowered (im- began impounding, silt flowed into the reservoir area and contin- pounded and unloaded). During that time, there were 243 incidents, ued downstream unimpeded. 167 of which were identified as novel and unexpected, accounting for 68% of the total incidents. Data gathered between 2003 and 2008 determined that the annu- al sediment flow into the reservoir from upstream had decreased In an effort to reduce the occurrence of geological disasters caused to about 198 million tons, mainly because a number of large by the operation of the reservoir, the Wuhan-based Changjiang Wa- reservoirs built upstream of the Three Gorges area were trapping ter Resources Commission (CWRC) asked dam authorities to reduce sediment. Meanwhile, during the same period, annual sediment the rate of impoundment and unloading, keeping the daily maximum flows out of the reservoir into the lower river section below the amplitude (changes in the reservoir level, up or down) to less than dam decreased to only 61 million tons. 0.5 meters. The measures suggested by the CWRC worked: docu- mented occurrences of geological disasters and related dangerous This means that, before the dam’s impoundment, almost 100% situations in the Chongqing area fell to 16 and 13 in 2010 and of the sediment flowing down the Yangtze and its tributaries was 2011 respectively. 3 In early March 2012, I traveled to the Wu Gorge of the Three Gorg- Experts at the monitoring station also informed me that since es, to visit Aunt Wang , a resident of Gongjiafang Village, located 2000, a budget of more than 10 billion yuan (1.6 billion USD) has about 4 kms downstream of the Wushan Port.
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