Seven major river basins in China face flood threat

Seven major river basins in China are at risk of flooding in the upcoming flood season, which could lead to a complex flood defense situation, said an official of the Ministry of Water Resources on Sunday.

According to the forecast, precipitation will be distributed mainly in the north, with less rainfall expected in the south from late July to early August.

Areas that are likely to experience 20 percent to 50 percent more rainfall include the Songhua River and the Liao River, the Haihe River Basin (Zhangwei River and Ziya River), the middle and lower reaches of the Yellow River, the Huaihe River Basin (Yi-Shu-Si Water System), the upper reaches of the Yangtze River and the Hanjiang River.

The southern Yangtze River Basin (Dongting Lake and Poyang Lake water systems), the Pearl River Basin (Beijiang River, Dongjiang River and Hanjiang River), and Minjiang River are expected to have 20 percent to 50 percent less rainfall.

Global warming has intensified the water cycle and increased saturated water vapor. Studies have shown that for every 1 degree Celsius increase in atmospheric temperature, the water vapor content of the atmosphere increases by 7 percent. This makes extreme rainstorms more likely, which can easily trigger floods in small and medium-sized rivers, mountain torrents and urban waterlogging. These events pose a significant challenge to flood prevention and disaster relief efforts.

The official of the Ministry of Water Resources also noted that there are a large number of small and medium-sized reservoirs, dangerous reservoirs, and silt dams in China. Many of them have low flood resistance ability and pose a significant flood control risk. Additionally, there are many water conservancy projects under construction this year, some of which will need to be carried out during the flood season, increasing the safety risks of these projects during the flood season.

(Cover image via CFP)