Patrol ship captain Zhou Wei is exhausted as unprecedented droughts have stranded numerous vessels along the Yangtze River, the most important shipping route in China.

"It was very rare in the past 20 years that ships ran aground every day as we've seen since the past days," Zhou told China Daily on his ship under the Changjiang Wuhan Waterway Bureau.

The severe drought along the Yangtze River since November has snarled water transportation, dried up electricity output at dams, damaged farmland and affected hundreds of thousands of people in Central and North China.

These impacts are partially from the construction of the Three Gorges Dam, according to a statement from the State Council, China's Cabinet, which said that while the dam provides huge and comprehensive benefits, problems have also emerged.

Some experts have voiced concerns about a possible connection between the hydropower stations and the negative effects that have been increasingly witnessed by residents along the Yangtze River.

"We should study the lessons brought out by the Three Gorges Dam, instead of merely blaming it," Ma Jun, director of the Institute of Public and Environmental Affairs, said on Thursday, suggesting the government to seriously reconsider the construction of hundreds of hydropower stations that are under way in the upper reaches of the Yangtze River.

The water level in Jiujiang, Jiangxi province, in the lower reaches of the Yangtze River, dropped to 2.64 meters on Thursday, hitting a historic low, according to the latest statistics from the Changjiang Waterway Bureau.

Although many people have pointed to the Three Gorges Dam as the cause of the problems, Wang Hai, director of the transport division of the China Three Gorges Corporation, told China Daily that things might be worse without the dam.

During the past two weeks, the dam has opened sluice gates to allow more water to flow downstream, easing the drought and raising the water level in the lower reaches, he added.

The Three Gorges Dam has twice increased the water discharged downstream in May, raising the water level in Hankou, Hubei province, to 3.81 meters on Thursday from 2.87 meters on May 4, official statistics showed.

"It's the weather to blame instead of the dam," Wang said.