The Chinese government said on Wednesday that the Three Gorges Project, the world's biggest hydropower complex, had affected shipping, irrigation and water supply downstream on the Yangtze River.

The disclosure came after the State Council passed plans for future work on the project and for the prevention and treatment of water pollution in the downstream valley.

The giant project is also facing problems that need immediate solutions, such as the livelihoods of people displaced by the project, the protection of ecosystems as well as the prevention and treatment of geological hazards, according to a statement issued after the State Council conference.

Some of the problems had been expected during the research and design of the project, with the others emerging throughout the construction period, said the statement.

Construction of the project started 17 years ago and was announced as preliminarily complete in 2009.

"As to the irrigation and water supply issues, demand for water has increased rapidly along the middle reaches downstream when the project was under construction," said Wang Jingquan, a senior official of the flood control and drought relief office affiliated with the Yangtze River Water Resource Committee,?on Wednesday.

"And water pollution in these areas has made the situation worse," said Wang.

In the plan for upcoming work on the project, the country will cope with the negative impacts inflicted downstream of the dam, according to the statement.

Projects will stabilize water flow, reinforce river levees, improve waterways and upgrade water-pumping facilities, it said.

In addition, the plan set targets for 2020 for raising the living standards of people displaced by the project, including a universal social safety net, improved infrastructures and equalized public services.

In the second plan passed at the conference, water pollution in the middle reaches of the Yangtze River will be addressed during the 12th Five-Year Plan (2011-2015) period to ensure the supply of clean drinking water.

The area is China's most densely populated region, its most developed and also among the regions most burdened by environmental pollution.