YICHANG, July 28 (Xinhua) -- China's Three Gorges Dam was tested for the second time this month when the swiftest water flow of the year hurtled down the swollen Yangtze River on Wednesday morning.

Flow rates as high as 56,000 cubic meters per second were recorded at the dam at 8 a.m. Wednesday, dam engineers said.

The dam withstood the flow with a water discharge rate of 40,000 cubic meters per second, meaning 16,000 cubic meters of water per second accumulated in the reservoir behind the dam.

The safety monitoring results of the dam during the second flood peak have met engineers' predictions to prove its ability to contain flood waters, said Cao Guangjing, chairman of the China Three Gorges Corporation.

The water level in the reservoir had risen to 158 meters at 8 a.m.Wednesday, about 17 meters below its maximum capacity of 175 meters.

Officials expect the water level to rise to 161.5 meters Friday, a spokesman with the Yangtze River hydrology bureau said Wednesday.

Continuous downpours in recent weeks have raised water levels in the upper reaches of the Yangtze.

Water flows on the river's upper reaches reached 70,000 cubic meters per second on July 20 -- the highest level since the dam was completed last year and 20,000 cubic meters more than the flow during the 1998 floods that killed 4,150 people.

Ship traffic through the dam resumed last Thursday after the first peak flow passed. But shipping was halted again at 10 p.m. Tuesday as the second round of floodwaters approached.

After shipping service was suspended, a road near the dam was opened for vehicles to transport goods and people across the dam.