Criticism on Three Gorges Dam

Criticism

[edit] Environmental impact
Currently, the quality of water in the higher banks of Yangtze is falling rapidly, due to the dam's preventing dispersal of pollutants; algae blooms have risen progressively since the dam’s construction; and soil erosion has increased, causing riverbank collapses and landslides.[23] The report detailing this was officially released in September 2007.[19] Senior Chinese government officials and scholars said the dam could cause a “huge disaster ... if steps are not taken promptly.”[23] The same scholars and officials previously had defended the Three Gorges Dam project.[24] Xinhua News Agency also reported that tens of billions of yuan had been spent to prevent pollution and geological disasters by tree planting, measures to maintain biodiversity, shutting 1500 polluting industrial and mining enterprises and building 70 sewage and waste treatment plants, all of which are "progressing well." [24]

Three Gorges Dam
Of the 3,000 to 4,000 remaining critically endangered Siberian Crane, a large number currently spend the winter in wetlands that will be destroyed by the Three Gorges Dam[citation needed]. While logging in the area was required for construction which adds to erosion, stopping the periodic and uncontrolled flooding of the river will lessen bank erosion in the long run. The build up of silt in the reservoir will, however, reduce the amount of silt transported by the Yangtze River to the Yangtze Delta and could reduce the effectiveness of the dam for electricity generation[citation needed] and, perhaps more importantly, the lack of silt deposited in the peninsula could result in erosion and sinking of coastal areas[citation needed].
[edit] Effect on local culture and aesthetic values
The 600 kilometre (375 mi) long reservoir will flood some 1,300 archaeological sites and alter the appearance of the Three Gorges as the water level rises over one hundred meters at various locations.[citation needed] Cultural and historical relics are being moved to higher ground as they are discovered but the flooding of the Gorge will undoubtedly cover some undiscovered relics. Some other sites cannot be moved because of their size or design.[citation needed]
These historical sites contain remnants of the homeland of the Ba, an ancient people who settled in the region more than 4,000 years ago.[citation needed] One of the traditions of the Ba was to bury the dead in coffins in caves high on the cliff, some of which will soon be submerged.[citation needed]

[edit] Sedimentation
There are two hazards uniquely identified with the dam:[25] One is that sedimentation modeling is unverified [citation needed]and the other is that the dam sits on a seismic fault.
Excessive sedimentation can block the sluice gates which can cause dam failure under some conditions. This was a contributing cause of the Banqiao Dam failure in 1975 that precipitated the failure of 61 other dams and resulted in over 200,000 deaths. Critics believe that the Yangtze will add 530 million tons of silt into the reservoir on average per year; in time, this silt would pile up behind the walls of the dam, clogging the turbines' entranceway [citation needed]. Further, the absence of silt down stream would have two dramatic effects:
Unburdened by silt, the Yangtze below the dam would flow more quickly[citation needed]. This, in turn, would cause the river to scour the banks and riverbed more severely, even to the point of altering the character and predictability of the river itself. In addition, flood diversion dikes along the river would require expensive and continual re-strengthening and rebuilding.
The city of Shanghai, more than one thousand miles (1600 km) away from the dam, rests on a massive plain of sediment. The "arriving silt -- so long as it does arrive -- strengthens the bed on which Shanghai is built... the less the tonnage of arriving sediment the more vulnerable is this biggest of Chinese cities to inundation..."[26]
Also, the weight of the dam and reservoir can theoretically cause induced seismicity, as happened with the Katse Dam in Lesotho. Others point out that such criticism, purely theoretical in nature, was never leveled at other “mega-dams” such as the Nile’s Aswan Dam or the Itaipu Dam between Brazil and Paraguay.

[edit] National Security Concerns
In an annual report to the United States Congress, the Department of Defense cited that in Taiwan, “proponents of strikes against the mainland apparently hope that merely presenting credible threats to China’s urban population or high-value targets, such as the Three Gorges Dam, will deter Chinese military coercion.”[27] The notion that the Military of the Republic of China would seek to destroy the Dam provoked an angry response from the mainland China media. People’s Liberation Army General Liu Yuan was quoted in the China Youth Daily saying that the People’s Republic of China would be “seriously on guard against threats from Taiwan independence terrorists”.[28]

[edit] Future projects upstream
In order to maximize utility of the Three Gorges Dam and cut down on sedimentation from the Jinshana tributary of the Yangtze river, China plans to build a series of dams upstream of the Yangtze river, including Wudongde, Baihetan, Xiluodu, Xiangjiaba, and downstream of Jinsha. The total capacity of those four dams is 38,500 MW, almost double the capacity of the Three Gorges. There are also another eight dams in the midstream of the Jinsha and eight more upstream of it.[29]