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Yellow River, China's second longest, was the country's most polluted river in the first half of this year, due to a lack of water flow, said the State Environmental Protection Administration (SEPA) in Beijing Tuesday.

In a report on the water quality of China's major rivers, SEPA said that of the Yellow River was poor, with 39.5 percent lower than Grade 5, the lowest grade.

 

According to the report, one of the major pollution indexes is COD, or Chemical Oxygen Demand, a measure of pollutants in natural and waste water to assess the strength of waste such as sewage and industrial discharge.

 

The report ranked the seven major rivers in China in terms of pollution degree in the first six months of this year. The Yellow River took first place and China's longest river, the Yangtze, sixth place.

 

The report said that the poor quality of the Yellow River water resulted from the reduction of water flow this year, which dropped 32-50 percent from the average of previous years.

 

Earlier statistics from the Ministry of Water Resources indicated an unusually severe drought in the Yellow River Valleys and water flow in its tributaries was down to the lowest level in 50 years.

 

The 5,464-km Yellow River originates in the Qinghai-Tibet Plateau and winds its way through eight provinces and autonomous regions before reaching the Bohai Sea in east China. It provides water to 12 percent of China's population and irrigates 12 percent of all its arable land.

 

The latest monthly report showed that the water quality of the Yellow River improved in July, but the tributary water quality was still in bad condition.

 

The report also said that nitrogen and phosphorus pollution was serious in China's major lakes including Taihu, Dianchi and Chaohu lakes, with the water quality lower than Grade 5.

 

(Xinhua News Agency August 19, 2003)