In the early days of the Three Gorges Project, the primary role of propaganda was to solve the flood problem in the middle and lower reaches of the Yangtze River once and for all. The slogan of that year was "The day when the Three Gorges Project is completed is the time when the Yangtze River bid farewell to the flood".
However, according to media propaganda, this slogan has become more and more low-key after completion. When it was completed in 2003, it was said that "The Three Gorges Dam is impregnable and can resist the once-in-a-century flood", but in 2008 it became "The Three Gorges Dam can resist the once-in-a-century flood". Last year, it was declared that "the Three Gorges Dam cannot be counted on for flood control this year".
2. The settlement of sediment deposition was not as smooth as expected.
Sediment deposition in dams is a major problem in water conservancy construction. It is reported that the Three Gorges Reservoir adopts the method of "storing clear water and discharging muddy water" to deal with the problem of sediment discharge, that is, increasing the displacement to discharge muddy water from the reservoir in flood season and accumulating a large amount of clear water in dry season can reduce the sediment deposition in the reservoir, which is considered as a great pioneering work in the history of water conservancy. However, it has been reported recently that this method can only discharge about 70% of the sediment initially monitored by the reservoir. According to monitoring, from 2003 to 2007, 200 million tons of sediment were put into the reservoir every year, and the reservoir silted up about 65.438+300 million tons.
3. Water transfer and power generation still need to be coordinated.
The biggest feature of water conservancy projects is to cut down abundant crops to supplement drought and adjust the balance between drought and flood. However, for the Three Gorges Company, power generation is their source of income, which has certain contradictions with water transfer. When talking about this year's drought, Wang Jingquan, deputy inspector of the Flood Control and Drought Relief Office of the Yangtze River Water Resources Commission, said that the previous "off-season peak" made the Three Gorges use a lot of water to generate electricity, which aggravated the downstream drought. Wang Yintang, director of the Hydrological Basic Theory Research Office of nanjing hydraulic research institute Water Resources Research Institute, also believes that the Three Gorges Project is widely used for power generation, which will objectively cause the phenomenon of "water shortage" downstream.
Second, the environmental impact: may be exaggerated, but it is still very serious.
Drought is thought to be related to the Three Gorges Project.
1, the accusation of "affecting the climate" is groundless.
In recent years, the climate in southern China is unusually frequent, with extreme heat, drought, rainstorm and other abnormal weather in Sichuan, Chongqing and other places, and the Three Gorges is often targeted. The basic conclusion of the Environmental Impact Report of the Three Gorges Project approved by the State Environmental Protection Administration is that after the completion of the Three Gorges Reservoir, the impact on the temperature, humidity, wind and fog in the reservoir area and its adjacent areas will generally not exceed 10 km. Zheng Guoguang, member of the Chinese People's Political Consultative Conference (CPPCC) and director of the China Meteorological Bureau, said that some people think that the Three Gorges reservoir area has had a serious impact on the climate in the vast areas around the Three Gorges, and it is not scientific to attribute some extreme weather and climate events to the impact of the Three Gorges Project.
2. The task of environmental management in reservoir area is arduous.
According to the Report on the Protection and Development of the Yangtze River issued by China Academy of Sciences, World Wide Fund for Nature and Yangtze River Water Conservancy Commission in 2007, the pollution problem in the Three Gorges reservoir area is severe. In 2003, after the Three Gorges Reservoir Area was impounded to 135 meters, the monitoring results showed that the Three Gorges Reservoir Area was 65,438 meters during and after impoundment. At the same time, a large number of immigrants reclaimed wasteland, which also aggravated water pollution and caused soil erosion. According to the report, ground pollution sources are the main pollution sources in the Three Gorges reservoir area, accounting for 60%-70% of the total pollution, mainly from the use of pesticides and fertilizers in the reservoir area.
3. Compared with earthquakes, landslides are more important geological influences.
The Three Gorges Project was once blamed as one of the causes of the earthquake in the reservoir area. In fact, the relationship between the dam and the earthquake can not be proved by the current observation methods, but the landslide is already a problem worthy of attention. According to Xinhua News Agency, statistics of Chongqing reservoir area show that as of March 18, 2009, due to experimental water storage and water withdrawal, geological disasters occurred in Wushan, Wuxi, Fengjie, Yunyang, Kaixian and Wanzhou counties in Chongqing reservoir area 166, with a total amount of 60.24 million cubic meters. It is worth noting that among 166 disaster (danger) points, the number of newly added sudden disaster (danger) points reaches 12 1. The Three Gorges Reservoir stores water from 145 meters to 175 meters every year, and then falls back to 145 meters. The 30-meter drop is equivalent to the once-in-a-century Yangtze River flood, and the test of the reservoir bank slope can be imagined.
Third, the role of shipping needs long-term development.
Chongqing has not yet welcomed a 10,000-ton ship.
1, "the direct flight of the giant ship to Chongqing" is difficult to achieve at present.
During the design and demonstration of the Three Gorges Project, an attractive blueprint of "10,000-ton ship going directly to Chongqing" was put forward. But in fact, the river-crossing bridges in the middle and lower reaches of the Yangtze River have already formed a hundred bridges to lock the river, and the huge ship cannot pass under the bridge and enter the upper reaches of the Yangtze River.
Regarding the concept of "a huge ship entering Chongqing", the appearance of the Three Gorges has straightened out the upstream channel, while whether the downstream should break down the bridge to make way for the ship has caused a continuous debate.
2. The transportation efficiency needs to be further improved.
According to public information, at the beginning of the design of the Three Gorges Shiplock, it was determined that the one-way capacity was 50 million tons/year, and the two-way operation was 654.38 billion tons. In fact, since the opening of the Five-level Lock of the Three Gorges Ship Lock, the capacity of the two-way lock has been saturated to 50 million tons. And because the permanent lock is divided into five levels, the traffic speed is relatively slow. Theoretically, it takes 2 hours and 40 minutes to cross the gate, but in practice, it often takes more than 3.5 hours to cross the gate. Chongqing transportation department proposed to demonstrate, plan and finally build the second double-line five-level lock or the second ship lift on the Three Gorges Dam as soon as possible, and said that "this is the fundamental way to open the shipping bottleneck of the Yangtze River".