Vessels' transit through the Yangtze River's Three Gorges Dam has been suspended for the second time this month as engineers at the dam brace for the second flood waters of the year to hit.

The water flow rate through the dam will peak at 56,000 cubic meters per second on Wednesday, said a Three Gorges Corporation official.

At 5 p.m. Sunday, the flow rate was 40,000 cubic meters per second.

The flow rate hit 48,500 cubic meters per second at 8 a.m. Tuesday.

Shipping services were suspended at 10 p.m. Monday. They will resume once the flow rate drops to 45,000 cubic meters per second.

More than 100 vessels are waiting either side of the dam.

Shipping services were first suspended at 11 a.m. on July 19 for the first peak flow of the year on July 20, when water flow rates reached 70,000 cubic meters per second. That flow rate was more than that during the 1998 floods that killed 4,150 people. It was also the highest flow rate since the dam became fully operational in 2009.

The dam reopened on July 22, two days after the peak flow.

As of Tuesday, accumulated precipitation since June 16 in 70 percent of the drainage areas of the Yangtze River had exceeded 50 millimeters, after three rounds of rainstorms, said Cai Qihua, deputy head of the Yangtze River Flood Control Office.

Separately, in Wuhan, capital city of central China's Hubei Province, water levels on the Hanjiang River have stayed above the danger level for seven days now, said an official in the hydrology bureau of Changjiang Water Resources Commission.

The water level is expected to reach 30.5 meters at the river's Xingou Station, which will be the second highest level since 1998.

The Danjiangkou Reservoir on the Hanjiang River has buffered the flood which peaked July 19, when the water flow rate reached 27,500 cubic meter per second, said Liu Song, deputy director of the reservoir dispatch center of Hanjiang River Corporation.

The Danjiangkou Reservoir had greatly reduced the burden on the Three Gorges Dam, Liu said.

"Without the Danjiangkou Reservoir, the situation would be much more severe and the flood would have caused many more losses," Liu said.

As of Tuesday, the continuous rains had doubled the water area of Danjiangkou Reservoir and increased the Hanjiang River's width by 10 percent, said an official of Wuhan climate enter of Hubei Meteorology Bureau.

The water area of the reservoir reached 611.6 square kilometers, up 55.4 percent from July's 393.6 square kilometers, the official said.

The Danjiangkou Reservoir this week began to reduce discharged water flow rate to lessen the impact of the flood downstream, said an official of the Danjiangkou water resources administration.

Two gates were closed at 6 p.m. Monday and the discharged water flow rate was reduced from 6,210 to 4,800 cubic meters per second.