The great river goes east, mighty and mighty,Yangtze RiverIt is the longest river in China and the worldFlowOne of the largest rivers. Located inYangtze RiverUpstreamThree Gorges DamIt is the largest and largest in the worldHydraulic engineeringIt stands majestically on the majestic mountain gorge and has become the pride of China's engineering technology and wisdom. However, 17 years after the dam was built, one of the problems that has been plaguing people has been the accumulation of large amounts of sediment. The accumulation of sediment in the reservoir has sparked concern and discussion, but what are the consequences of dam siltation?
First of all, the accumulation of sediment can seriously affect the downstreamShipping。Due toThree Gorges Dam, the riverbed materials in the river could not flow naturally, resulting in an increasingly narrow waterway. When the river carries a large amount of sediment into the reservoir, the flow slows down and the sediment is deposited in the reservoir. Over time, the siltation of the reservoir is getting worse and worse, givingShippingBrought a lot of trouble. Moreover,Three Gorges DamYesYangtze RiverOnce the waterway is blocked, it will have an immeasurable impact on the economic development and transportation of the upstream area.
Secondly, sediment accumulation will also increase in the upstream areaFloodingRisk. InFloodingSeason,Yangtze RiverWater level**, the amount of sediment carried by the river will also increase significantly. Due to the siltation of the reservoir leads to a decrease in the water storage space of the reservoir, whenFloodingWhen it comes, the reservoir can't take on moreFlooding, thus increasing the upstream areaFloodingRisk.
In addition, sediment accumulation can adversely affect water quality. Sediment contains a large amount of suspended matter, and when the river water carries sediment into the reservoir, the suspended matter in the water will increase, reducing the transparency of water quality. Some pollutants may further pollute water bodies, destroy the ecological balance, affect the survival and reproduction of aquatic organisms, and even pose a threat to human health.
To solve this problem,Three Gorges DamThe strategy of storage and turbidity removal was adopted. During the flood season,Three Gorges ReservoirBy lowering the water level, it is controlled below the flood control warning level of 145 meters, and the discharge of large sediment contentFloodingto the downstream, thereby reducing sediment accumulation in the reservoir area. After the flood season, when the sediment content of the upstream water body decreases, clean water is stored. This operation not only reduces the sediment accumulation in the reservoir area, but also ensures the normal operation of the reservoir.
In addition, in order to better drain the sand,Three Gorges DamA series of sand flushing holes, sand flushing gates and other devices were designed. For example, the dam has 22 low-elevation discharge holes, which can be released when the water level reaches 145 metersFlowwater flows, thereby speeding up the discharge of sediment. Through these well-designed hydraulic structures andScienceThe method of running the reservoir,Three Gorges DamSuccessfully controlled the siltation problem.
Although the accumulation of sediment can pose a series of problems, it passesThree Gorges DamThese problems have been mitigated and controlled to a certain extent. According to the monitoring data,Three Gorges DamThe amount of sediment accumulated is much lower than the theoretical value, which proves the effectiveness of the storage and turbidity removal strategy. In addition,Three Gorges DamDredging is also carried out on a regular basis to remove heavier sediments from the river sections, ensure the water storage capacity of the reservoir and the efficiency of power generation, maintenanceYangtze RiverThe ecological balance of the upper reaches of the river section andShippingSafe.
In short, thoughThree Gorges DamIn the early stage of construction, it faced many doubts, especially the problem of sedimentation, which caused widespread concern, but passedScienceThe operation method and technical means of the dam solve the problem of sediment accumulation to a certain extent. For a long time, China has been exploring and researching solutions to the problem of sediment sedimentation, and has achieved a series of important results. Sediment accumulation is a global problemThree Gorges DamIt provides useful experience and enlightenment for solving this problem, and demonstrates China's technological strength and wisdom.