CHENGDU - Unprecedented flooding in Southwest China's Sichuan province has forced more than 300,000 people to evacuate, the local government said Monday.

The Qujiang River, a tributary of the Jialing River that feeds the Yangtze, China's longest waterway, began to swell Sunday.

By midday Monday, the water level had reached 23.1 meters, 6.6 meters above the alert level, the city of Guang'an's Flood Prevention and Drought Relief Office said in a press release.

It said the flood has hit Guang'an city proper as well as 49 townships and neighborhoods. About 2,000 homes have been toppled and more than 10,000 others have been damaged. In the city center alone, 40 streets have been submerged.

The worst is yet to come, however, as the flood is expected to crest at 27.13 meters at 3 pm, the water's highest since record-keeping began in 1847.

The government had evacuated over 300,000 people from the city proper by midday to minimize risks, as flood control experts estimate that all major streets will be submerged and flood water could measure 10 meters in the deepest areas.