The discharge, most of it from factories, increased by 88 million tons from 2004, and more than 66 percent of the water in the river was unfit for drinking, the report said.

"Apart from pollution, the river is suffering from a dramatic decrease in water flow, mainly due to low precipitation and overuse," the committee said in its annual report.

The 5,400-kilometre (3,350-mile) river originates in the Tibetan plateau in northwest China's Qinghai Province and flows through seven other provinces and regions before emptying into the Bohai Sea.

Known as the cradle of early Chinese civilization, the Yellow River supplies water to more than 155 million people and 15 percent of China's farmland, Xinhua said.

Officials earlier said excessive exploitation of river's water resources had resulted in lower sections totally drying up on more than 1,000 days between 1972 and 1999.

Although the phenomenon has not occurred recently due to a number of intervention measures such as water diversion projects and water price rises, officials say the risk remains.

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