□ Du Ruoyuan
By June 15, the dam will have completed the first stage-135m water level, and will gradually store water to175m elevation in the next few years. The Three Gorges Project will reshape the Yangtze River flowing through the ages. Let's approach the Yangtze River and see what will happen to the mother river.
A new landscape will appear in the Yangtze River: most of the rapids, rapids and shoals in the upper reaches will disappear; There are many forks in Pinghu River, and the islands of Three Gorges are dense.
On May 24th, the Zigui Port Passenger Terminal, known as the first port on the Three Gorges Dam, was officially opened. The day after the impoundment of the Three Gorges Reservoir reaches 1.35 meters, the Three Gorges permanent ship lock will begin trial navigation, which marks the end of the history of navigation obstruction at the Three Gorges dam site.
After the Three Gorges reach1.35m impoundment, the Three Gorges reach with a total length of1.92km in the upper reaches of the Yangtze River will first show the beautiful scenery of Gaoxia Pinghu. From Yichang to Chongqing, 550 kilometers of the 660-kilometer Yangtze River waterway is in rapids, rapids and shoals. After water storage, the backwater of the reservoir will reach Fengdu, Chongqing. The depth of Xiling Gorge River will increase by 60 meters, Wuxia River by 55 meters and Qutangxia River by 50 meters. With the increase of water depth, most rapids, rapids and shoals will disappear. There will be many new landscapes in Pinghu, Three Gorges, with many forks and many islands. At the same time, due to the slow flow rate, the navigation speed will be greatly improved, the shipping cost will be reduced, and the navigation in the upper reaches of the Yangtze River will be safer.
During the storage period of 15 days, the water level on the Three Gorges Dam rose by nearly 70 meters, and the most affected reach of the Yangtze River was mainly Yichang to Huangweikou. Wang Liang, an expert from the Yangtze River Waterway Bureau, analyzed that during the impoundment period, the flow will only be 1/6 of the normal year, and the situation of "low water before flood season" will be more serious than in previous years due to the sharp drop of the flow in the middle reaches of the Yangtze River. However, after a short period of water storage, a large amount of sediment in the upper reaches of the Yangtze River is trapped in the reservoir area, and the discharge of clear water will cause riverbed erosion and river regime adjustment in the lower reaches of the dam, which will bring new problems to the Yangtze River channel.
According to experts, after storing water to 135 meters, it can be adjusted by the reservoir to increase the flow in dry season and increase the water depth in the middle reaches. It is estimated that the depth of shoals in the middle reaches of the Yangtze River will increase by about 0.2 meters for every discharge of the Three Gorges Reservoir 1000 cubic meters. In this way, through the regulation of the Three Gorges Reservoir, it is predicted that the channel depth of Jingjiang reach in the middle reaches of the Yangtze River will increase by 0.5 m during the dry season, and many shoals will disappear.
After the impoundment of the Three Gorges, the Chuanjiang waterway was divided into three parts, and the water flow slowed down. Chongqing section of the Yangtze River used to be a single large-scale mountain waterway, which was divided into two parts: Wushan Wu Yuxi to Zhongxian Taojia Shipan became the reach of the reservoir area; The reach from Taojia Shipan in Zhongxian to Qingxichang in Fuling has become a fluctuating backwater area. Above Qingxichang, Fuling is still a mountain waterway. Among them, most of the signal stations will be cancelled in the long channel of the reservoir area, and only three traffic control sections, Qingshidong, Kongwangtuo and Fengxiang, will be reserved.
When the reservoir reaches 135 meters, the Three Gorges Project also has preliminary flood control measures, but the lower reaches of the Yangtze River are not affected much. The operating water level of the Three Gorges Reservoir is1.35m.. When the Jingjiang reach of the Yangtze River floods and the water level in Shashi reaches 45 meters, the Three Gorges Project can adopt unconventional dispatching measures to raise the water level of the reservoir from 1.35 meters to 1.40 meters, which will effectively alleviate the "heart disease" in the middle and lower reaches of the Yangtze River for thousands of years.
After the completion of the Three Gorges Reservoir, it not only improves the upstream navigation channel, but also fundamentally changes the current situation of poor navigation in the middle reaches of the Yangtze River in dry season, which will create a new era of Yangtze River shipping.
The Three Gorges Reservoir is just around the corner, and the Yangtze River waterway, which has been flowing for thousands of years, has responded to the upcoming new changes in advance.
Zhou Junan, an expert from the Yangtze River Waterway Bureau, said that the water storage will rise by about 5-6 meters every day in the initial stage and by about 3-4 meters in the later stage. During the impoundment period, the berths of channel stations in the reservoir area should move continuously with the rising water level, and some channel stations and docks in the middle reaches should be adjusted with the falling water level.
After two years of reconnaissance, investigation and experiment, the Yangtze River Waterway Bureau has formulated a set of scientific countermeasures in terms of navigation standard layout, signal disclosure and beach dredging, and intervened in advance.
In the next 17 years, the state will invest more than1600 million yuan to build a "golden waterway".
The Yangtze River is the largest river in China and the most important main waterway for inland navigation in China, and its freight volume accounts for 40% of the national inland freight volume. In the national opening-up and western development strategy, the Yangtze River shipping plays a vital role. However, for a long time, the natural state of the Yangtze River waterway has seriously restricted the rapid development of the Yangtze River shipping.
Liu Hengwei, secretary of the Party Committee of the Yangtze River Waterway Bureau, said that in 2003, the Ministry of Communications formulated the development plan of the Yangtze River trunk waterway. In the next 17 years, the state will invest more than 654.38+0.6 billion yuan to comprehensively harness the Yangtze River waterway on a large scale, with a total length of 2,838 kilometers from Shuifu Port in Yunnan to the Yangtze River estuary in Shanghai. Among them, 654.38+0.2 billion yuan will be directly used for waterway regulation to systematically regulate the 465.438+0 shoal in the middle and lower reaches of the Yangtze River. Through the gradual regulation of key shoals, the water depth scale of the Yangtze River channel will be improved. From Chenglingji to Wuhan, a fleet of 10,000-ton oil tankers consisting of 3,500-ton oil barges will be navigable, and 3,000-ton seagoing vessels can also use the natural water depth of the channel to navigate. Tongling to Nanjing is navigable for 5000-ton seagoing ships; Below Nanjing, ships of more than 50,000 tons can be navigable.
After seven years of construction, the navigation aid project in the Three Gorges reservoir area with an investment of 79 million yuan will be completed soon. All the new lighthouses are large and brightly lit. In the past, the humble signal station also built a European landscape, and the signal disclosure was fully automated. Standing on the majestic Three Gorges Dam, Liu Hengwei, secretary of the Party Committee of the Yangtze River Waterway Bureau, said excitedly: "After several years of development, the Yangtze River Waterway will become a golden waterway integrating tourism and shipping."