Experts from the Yangtze River Committee interpreted the Yangtze River flood situation this year
Our reporter Liu Zhiwei
The Yangtze River Basin is experiencing the 9th significant rainfall since the rainy season this year. Rainfall in the upper and middle reaches raised the water level of the Yangtze River in Wuhan. Starting in the afternoon of July 19, the water level of the Yangtze River in Wuhan began to rise slowly. Within 3 days, the Yangtze River No. 2 peak will arrive in Wuhan.
At 10 o'clock on July 20, the water level of Wuhan Guan reached 28.65 meters. At this time, the press conference of the Yangtze River Water Resources Committee of the Ministry of Water Resources (hereinafter referred to as the Yangtze River Committee) is being held in Wuhan. Chen Guiya, deputy chief engineer of the Yangtze River Committee, told reporters that the flood control situation in the Yangtze River Basin is still severe and may continue for some time. At present, it is seven times lower than eight times, the upper reaches of the precipitation increase, the middle and lower reaches of the water recede slowly, and it has entered a critical period of flood control.
A total of 9 significant rainfall processes occurred, with almost no intermittent rainfall
The rainfall process is frequent, intense and long lasting. Hu Xiangyang, director of the Bureau of Flood and Drought Disaster Prevention of the Yangtze River Committee, said that since June, there have been 9 significant rainfall processes in the Yangtze River Basin, and the rainfall process is basically non-stop. The center of heavy rainfall is located near the mainstream of the middle and lower reaches of the Yangtze River and the northern part of the two lakes. Among them, the lower reaches of the Wujiang River, the Lishui River, the main stream of the middle reaches of the Yangtze River, and the northern Poyang Lake water system are more than doubled. Especially in the first ten days of July, the ten-day rainfall in the middle and lower reaches of the Yangtze River was 1.6 times higher than the average over the same period, and the 10-day rainfall in the Poyang Lake system was 3.1 times higher than the average over the same period.
148 rivers were involved in floods above warning level
Floods above the warning level involve many rivers and have a wide distribution range. Hu Xiangyang introduced that since June, a total of 236 stations in the Yangtze River Basin have experienced over-alert floods, involving 148 rivers. Some rivers have experienced over-alert floods many times, including 160 stations with over-alert water levels and 35 stations with over-guaranteed water levels. 41 stations above historical water level.
According to statistics at 8 o'clock on July 20, there are still 14 stations in the Yangtze River Basin that have exceeded the history, 12 stations have over-guaranteed, 84 stations have been over-alert, and 70 rivers are involved. Among them, there are 6 ultra-historical sites in the Chaohu water system, 5 on the Chuhe River, 1 Ma'anshan on the mainstream of the Yangtze River, 1 Qingjiang Gaobazhou, 1 Hudu River, with an ultra-historical range of 0.13 to 0.88 meters; ultra-guaranteed , Super-police stations are mainly distributed below Jianli, the main stream of the Yangtze River, the upper and middle reaches of the Dadu River, Songzi River, Dongting Lake and Weilu, Poyang Lake and Weilu, Xihe, Chaohu, Chuhe, Qingyijiang, Shuiyangjiang, Jinsha Jiang and the upper reaches of the Yalong River.
The flood peaks of the middle and lower reaches of the mainstream have high water levels, which are in the forefront of history
At present, the flood peak water level of the middle and lower reaches of the Yangtze River is high, which is at the forefront of history. According to statistics, the flood peak water level of Lianhuatang Station on the mainstream of the Yangtze River is 34.34 meters, ranking 5th in history; the flood peak water level of Hankou Station is 28.77 meters, ranking 4th in history; Jiujiang Station is 22.81 meters, ranking second in history; Datong Station is 16.24 meters. The flood peak water level of Qilishan Station at the exit of Dongting Lake is 34.58 meters, ranking 6th in history; the flood peak water level of Hukou Station at the exit of Poyang Lake is 22.49 meters, ranking the second in history, only 0.01 meters from the guaranteed water level. The current time is at 20 o'clock on July 12, 2020.
2408 accidents were under timely control
As of July 18, 5 provinces including Hubei, Hunan, Jiangxi, Anhui and Jiangsu had reported 2,408 dangerous situations in the middle and lower reaches of the Yangtze River. According to the types of dangers, there are 1,040 piping, 715 flooding, 99 overflowing dangers, 87 crossing dike dangers, 132 landslides, 102 loopholes, 78 collapses, 61 falling nest dangers, and 18 breaching dangers. There are 36 cracks, 23 wind and waves scrubbing, 10 other dangers, and 7 reservoir dangers. Chen Guiya said that these are common dangers, and these dangers are currently under timely control, and most of the dangers have been dealt with.
419 shoals are used for flood storage, and the flood control effect is remarkable
Hubei, Hunan, Jiangxi, Anhui, etc. used 419 shoals to store floods in accordance with the "Yangtze River Flood Defense Program" approved by the State Council, and the flood control effect was significant. According to the calculations of Jiangxi Province’s Prevention Index, 185 single-return dikes in the Poyang Lake District of Jiangxi Province were used, with flood intake exceeding 2 billion cubic meters, lowering the water level of Poyang Lake by 25 to 30 cm.
In response to the recent flood conditions in the Chuhe River Basin, the Yangtze River Committee video connected Anhui Province and coordinated Jiangsu Province to open the Sanchawan Gate flood discharge; at 5 o'clock on July 18, in response to the severe flood control situation in the Chuhe River, Ma Jianhua, the director of the Yangtze River Committee, urgently organized a consultation and guidance Anhui Province made preparations for the operation of flood storage and detention areas and implemented it that night.
Hu Xiangyang introduced that in the process of defending the No. 1 flood of the Yangtze River, the Yangtze River Committee issued 27 dispatch orders, dispatching 29 controlled reservoirs in the upper and middle reaches of the Three Gorges Reservoir to intercept floods, with a flood storage capacity of more than 10 billion cubic meters and lowering Chenglingji (Lianhuatang ) The flood peak water level of the station is about 0.8 meters, the flood peak water level of the Hankou station is reduced by about 0.5 meters, and the flood peak water level of the Hukou station is reduced by about 0.2 meters. This prevents the Shashi station from exceeding the warning water level and achieves the goal of not exceeding the guaranteed water level at the Lianhuatang station.