A clean water supply returned on Monday to a part of a northeastern China county where thousands of people had suffered from polluted tap water during the weekend, local authorities said.

A woman takes care of her baby, who fell sick after drinking tap water contaminated by e-coli bacteria, at the people's hospital in Yilan county, Heilongjiang Province, on Sunday. [China Daily]

By Sunday afternoon, 2,675 households in seven residential areas in Yilan, Heilongjiang Province, had been affected by the contaminated water, according to an announcement on the county government's website.

As a result, about 9,000 people found themselves lining up in front of temporary water stations to get drinking water, Xinhua News Agency reported on Sunday. The consequences of not getting clean water were dire.

According to reports, many local residents had come down with intestinal illnesses.

"My baby, an 18-month-old, began to vomit and had diarrhea a few days ago," a female resident told the Heilongjiang Morning News on Monday.

"I sent him to the hospital yesterday, since he did not improve after he had taken medicine. Fortunately, his situation is taking a turn for the better now.

"I have now bought a lot of bottled water for my family, because I'm really worried."

The county government confirmed that excessive amounts of e-coli bacteria had been found in the water.

Zhang Wen, a county official, told Xinhua on Sunday that some of the underground water pipes there are old and cracked, allowing pollutants to enter the water stream.

By Monday afternoon, two of the seven affected residential areas had seen their water supplies restored, local authorities said.

Work to repair and disinfect the water supply system is still under way and is expected to be finished in the next two days, a staff member with the county government told China Daily on Monday.

Analysts said health emergencies resulting from polluted water have become more and more common in recent years. They said most of the emergencies can be traced back to discharges of industrial and sanitary wastewater.

In the latest such case, the drinking water going to nearly 300 rural households in Dafeng, a city of Jiangsu province, was infected with wastewater from a nearby chemical plant.

Jiangsu TV broadcast footage on Sunday showing muddy and yellowish water.

Since early April, hundreds of Dafeng residents have suffered from diarrhea and have sought treatment in hospitals, a local villager was quoted as saying.

The local government began to send clean water to the endangered households on April 20. As for the chemical plant blamed for the pollution, it has not issued a statement about the case, the report said.

Ma Jun, director of the Institute of Public and Environmental Affairs, a non-governmental group based in Beijing, told China Daily on Monday that water pollution can be prevented.

"For instance, sewer pipes in some cities are old," he said. "But local governments rarely pay much attention to such matters, which causes cities to be faced with greater risks of water pollution in the future."

Businesses in China have not been asked to give the public information about their discharges of toxic substances. That too has contributed to the harm done by the pollution emergencies, he said.

"The central government needs to urge its branches at all levels to strengthen their daily monitoring of water," he said. "Also, the punishments meted out to individuals and companies responsible for the pollution should be stricter."

So far, 320 million rural residents in China do not have access to safe drinking water. Among them, 190 million use drinking water that contains excessive levels of hazardous substances, according to the latest statistics from the Ministry of Environmental Protection.