Water quality further deteriorated in the Huaihe River, China's most polluted river, in November, with only 57.8 percent of the water considered safe for domestic, industrial or agricultural use.

The figure is about 15.5 percent points less than last year, according to the environment surveillance center on the Huaihe River.

The center carried out tests at 45 places along the river across Henan, Anhui, Jiangsu, Shandong and Hubei provinces, involving 20 indices including permanganate number index, ammonia and nitrogen content.

Chinese experts divide water quality into five grades. Grade I is the least polluted, while grade V water cannot even be used for irrigation.

The tests show only 35.5 percent of the water can be used as domestic water, 17.8 percent in industry, 11.1 percent in irrigation and 35.6 percent in none of the above.

Experts attribute the degeneration to scarce rainfall in the Huaihe River basin recently, preventing fresh water from diluting pollutants, which the towns and cities continue to discharge pollutants into the river.

The Huaihe River has suffered a drought since October and the rainfall has halved from last year, according to local observatory.

The Huaihe is one of China's major rivers, running through the country's east between the Yangtze and Yellow rivers.

In 1994, China launched campaign to clean the river, which has been heavily polluted since the 1980s, but recent media reports show the pollution remains unchecked despite a decade of expensive control efforts.

(Xinhua News Agency December 20, 2004)