After the Three Gorges Project started operating, the water levels in Lake Dongting changed due to the reservoir regulation. The researchers studied the effects of the project on the lake's water regime in 2006. They found that the water levels decreased and the discharge increased during impoundment. The impact varied across different parts of the lake, with the east being most affected. The study also identified two main mechanisms causing these changes: the faster drawdown of the Yangtze River and the reduced inflow from distributary channels.