Spill adds to problems of beleaguered Yellow River

The leak is the latest environmental disaster to affect China’s waterways, considered among the world’s most heavily polluted.

The diesel spilled from a broken pipeline on Wednesday into the Wei River, which feeds into the Yellow River, a water source for millions of Chinese.

Three counties and an industrial zone in western Shanxi province have been ordered to halt their use of river water, according to a notice issued by the local government. The areas have a combined population of about 850,000 people.

The warning contradicted earlier reports that the contaminated water had been contained after workers dug diversion channels and used floating dams and solidifying agents to try to stop the diesel spill.

“Relevant departments remind those living along the river that for the sake of safety, both people and livestock should suspend use of Yellow River water for drinking,’’ said the notice from the region’s Yuncheng city government publicity office.

Yuncheng is 720 miles southwest of Beijing.

The notice did not say how much of the slick had made it into the river, saying only that tests showed the leak “could create an impact on the water quality of the Yellow River.’’

China’s second-longest river has already seen its water quality deteriorate rapidly in recent years as discharge from factories has increased and water levels have dropped because of diversion for booming cities.

The pipeline’s owner, China National Petroleum Corp., said last week that it had plugged the leak and had removed a “large amount’’ of contaminated water, mud, and sand.

There was no immediate word on disruption of supplies from the pipeline, a key fuel conduit which links the capitals of northwest Gansu province and central Henan province. CNPC is China’s largest producer of oil and gas.

More than 20 percent of water tested in nearly 200 Chinese rivers was considered unsafe for use, according to a report by the Ministry of Environmental Protection on the state of the environment in 2007.

China’s Environmental Ministry has tried to shut down polluting factories along main waterways, but its power is limited because local environmental protection bureaus are under the control of local governments.

In 2005, carcinogenic chemicals, including benzene, spilled into the Songhua River, forcing the northeastern city of Harbin to sever water supplies to 3.8 million people for five days. The accident also strained relations with Russia, into which the poisoned waters flowed.