Authorities in the eastern Chinese province of Anhui have evacuated 17,000 people who live along the flooded Huaihe river, as water levels reached a record high.
The Xinhua news agency said officials blew up river dikes after the evacuation Sunday to release flood waters and prevent them from breaching the shore.
The news agency said the water level on the swollen tributary of the Yangtze has reached unprecedented levels and is expected to keep rising.
China's flood season usually starts around June and ebbs by September. Beijing says the world's largest hydroelectric project, the Three Gorges Dam will help tame the Yangtze.