How did the Three Gorges Dam change flooding along the Yangtze River in Hubei?

The Three Gorges Dam, located in Hubei province, was constructed with the primary objective of alleviating the periodic, catastrophic flooding that has historically plagued the middle and lower reaches of the Yangtze River.123

By creating an immense reservoir, the dam functions to regulate water flow, holding back significant volumes of water during periods of heavy monsoon rains to minimize downstream impact. For example, the dam proved effective during the 2010 rainy season by retaining floodwaters. Additionally, the dam helps lessen the impact of water-level variations downstream.12

However, the dam's efficacy as a flood-control tool remains a subject of debate. While officials have stated that the structure reduces damage and loss of life, critics point to events like the 2020 floods—where the reservoir neared maximum capacity—as evidence of the dam's limitations. During such extreme events, the dam must still open its floodgates to manage high water volumes, and flooding and landslides continue to pose risks to the basin.31