Water projects stand test of strongest floods in 20 years

Photo taken on July 27, 2020 shows floodwater being discharged from the Three Gorges Dam in Central China's Hubei province. [Photo/Xinhua]

Operation proves effective

The hard work of Chen and his colleagues has paid off. The operation of reservoirs in the upper and middle reaches of the Yangtze have played an important role in avoiding the large-scale evacuation of people near Dongting Lake, the second-largest freshwater lake in China, when the Yangtze was hit by the year's first flood early this month.

Chen Jionghong and Chen Guiya, the commission's deputy chief engineer, rebutted a recent report by Reuters that cast doubt on the effectiveness of the flood mitigation role of the Three Gorges Dam.

Before the Yangtze's first flood of the year arrived at the dam on July 2, the commission drafted a plan to mobilize the Three Gorges reservoir and other major reservoirs in the middle and lower reaches of the Yangtze to help keep the water level at Chenglingji hydrological station below 34.4 meters, which is the maximum design level for dikes in the section.

Aerial photo taken on July 27, 2020 shows floodwater being discharged from the Three Gorges Dam in Central China's Hubei province. [Photo/Xinhua]

Chenglingji is where the Yangtze meets Dongting Lake.

"The target was met. The highest water level at the station during the time only reached 34.34 meters," Chen Jionghong said, adding that a rough calculation by the commission showed that the water level could have exceeded 35.1 meters without the reservoirs' help.

If the water level at the station had exceeded the maximum level for dikes and kept rising, nearby flood detention areas would have had to be used. That would have necessitated the evacuation of a large number of people from areas to be inundated, he said.

"Our work is people-centered. That is to say, we have to guarantee the safety of people's lives and property," Chen Jionghong said.

Record high water levels at some hydrological stations at Poyang Lake, the country's largest freshwater lake, were cited by Reuters to support the claim that the Three Gorges Dam had failed to play its role in mitigating floods.

But Chen Guiya said that while the Hukou hydrological station, where the Yangtze meets Poyang Lake, is far from the Three Gorges Dam, calculations by the commission showed that the reservoirs in the upper and middle reaches of Yangtze had helped reduce the water level there by 0.2 meters during the first flood of the year.