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In 2022, the rainfall and runoff in the Yangtze River basin were significantly low, which indicate a severe drought happened in the Yangtze River. Since August, the water level in the middle and lower reaches has continued to decline and broke the record of the lowest water level in the history of the same period. Taipingkou and Ouchikou, which belong to the three outlets of the Jingjiang River, have been cut off nearly three months in advance. In this paper, the low water propagation characteristics in the middle and lower reaches of the Yangtze River and the diversion characteristics of the three outlets of the Jingjiang River were studied. At the same time, MIKE 11 is used to quantitatively analyses the operation benefits of the Three Gorges Reservoir. The research results show that (1) the propagation time during the low flow period has been extended to a certain extent, compared to flood period, for example, the propagation time between Yichang and Shashi stations, Shashi and Lianhuatang stations, Lianhuatang and Hankou stations, Hankou and Jiujiang stations, Jiujiang and Datongjiang stations are respectively 2h, 5h, 9h, 4h, and 8h longer; (2) the attenuation coefficient between Yichang and Shashi, Shashi and Lianhuatang, Lianhuatang and Hankou, Hankou and Jiujiang, Jiujiang and Datong are 0.99, 0.76, 1.00, 0.64 and 0.74, respectively; (3) after the construction of the Three Gorges Reservoir, from 2003 to 2021, the average diversion ratio of the three outlets of Jingjiang River was 12%, which is 17% less than that from 1956 to 1966, and is 3% less than that from 1981 to 2002; (4) the operations of Three Gorges Reservoir have effectively raised the water level of the main hydrological stations in the middle and lower reaches of the Yangtze River.
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