Water levels in the Yangtze River have changed due to the Three Gorges Dam. The researchers studied water level trends and causes using data from 1991 to 2022. They found that when the dam discharges less water, water levels decrease due to erosion. When discharges are higher, water levels increase slightly due to more resistance in the river. Flood levels in some years rose because of higher water levels downstream. This study helps us understand how dams affect rivers and can improve flood management globally.