The Three Gorges Dam, located on China's Yangtze River, saw its first flood of the year on Thursday.

The Three Gorges Dam, located on China's Yangtze River, saw its first flood of the year on Thursday.

At around 8 p.m. Thursday, the water flow rate in the upper reaches of the Yangtze River reached 39,000 cubic meters per second, said Yuan Jie, director of the Three Gorges Cascade Dispatching Center.

The criteria for defining a flood on the Three Gorges Dam is a water flow rate of 35,000 cubic meters per second or higher.

The flood was caused by heavy rains that began pounding the Jialing River basin in the upper reaches of the Yangtze on Wednesday, said Wang Hai, an official with the dam's construction and operation management bureau.

To ease pressure on downstream areas, the Yangtze River Flood Control and Drought Relief Headquarters has ordered the Three Gorges Reservoir to gradually increase the amount of water that it discharges to the river's lower reaches.

By 9 p.m., water levels at the Three Gorges Reservoir reached 147.28 meters, about two meters higher than the day's lowest level.

In 2010, more than 26 billion cubic meters of water were held back in the reservoir, which helped authorities to control flooding in the middle and lower reaches of the Yangtze, according to a report issued by the China Three Gorges Corporation on Sunday.