With a capability to handle a water level of up to 175 meters, the reservoir, which was completed in 2006, saw its water level rise to 160.17 meters on Saturday, according to the China Three Gorges Corp.

The ministry said it has instructed the company to increase outbound flow from 33,000 to 37,000 cubic meters per second.

As the Three Gorges Dam is tested by the biggest flood it has experienced so far this year, the water levels in most of Yangtze's river courses in its middle and lower reaches remain above their warning levels and some even reached record highs.

While major floods may occur in the Huaihe River, the water level in Taihu Lake, the country's third-largest freshwater lake, keeps rising slowly and has remained above the warning level for over 20 days, according to the ministry.

"The flood control situation is extremely grim," it said.