Pollution of the Yellow River, China's second longest river after the Yangtze, is getting worse, with over 66 percent of the water undrinkable, according to a newly released report on Yellow River Water Resources.

Only 33.3 percent of the water is category 3 -- ok for drinking, aquatic breeding, fisheries or swimming, down from 40 percent in the 1990s, according to the report, which is presented annually by the Yellow River Water Resources Committee to reflect the overall situation of the river, including water resources and water quality.

More than 4.35 billion tons of waste water were dumped into the Yellow River in 2005, about 88 million tons more than last year, according to the report.

More than 73 percent of the waste water was discharged from factories, 298 million tons more than last year, 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 5,464-km Yellow River originates in Qinghai Province in the country's northwest and flows through Gansu, Ningxia, Inner Mongolia, Shaanxi, Shanxi and Henan, 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.

In recent years, central and local governments have taken measures to curb pollution of the river, including huge investments in the construction of waste treatment plants and the forced closure of heavily polluting factories along the river.

Six more automatic water quality monitoring stations will be added to the existing two by 2010 along the Yellow River to help control the worsening pollution situation.

(Xinhua News Agency December 13, 2006)