Residents queue to get drinking water from a container in Mianyang, Southwest China's Sichuan province, July 27, 2011. [Photo/Xinhua]

CHENGDU - Residents have resorted to panic buying of bottled water after authorities in the southwestern city of Mianyang announced Tuesday that the city's major water source has been contaminated by flood-washed residue from a local manganese plant.

Residents have stormed supermarkets, stores and shopping malls for bottled water, despite the government's efforts to mobilize fire engines to send 375 tonnes of water to communities from Tuesday night through Wednesday morning.

The residue of the Xichuan Minjiang Electrolytic Manganese Plant in the county of Songpan in Aba Tibetan and Qiang autonomous prefecture was washed into rivers by heavy rains last Thursday and contaminated Mianyang's water source of the Fujiang River, according to a notice posted on the city government's official website, which was repeatedly broadcast through local media.

Ye Hongjian, general manager of the Mianyang Water Group, said Fujiang River is one of the city's three major water sources, which accounts for 70 percent of the drinking-water supply for some 300,000 people living the city's urban areas.

"I was at a tea house with my friends when I suddenly heard the warning Tuesday afternoon, but when I rushed to the nearest store, I saw a long queue of water buyers, and there wasn't a bottle on the shelves," said a woman surnamed Zhou.

Sales people with several major supermarkets and shopping malls, including Walmart and Parkson, said they have ordered more bottled water from elsewhere to cope with the buying spree.

The government has also sent messages through local media that it has made purchases of bottled water from neighboring areas.

"Please don't frantically buy bottled water. The supply can be guaranteed, and the prices can remain stable," said a government notice announced via Mianyang TV Wednesday morning.

Yu Xiaofeng, an emergency response official, said by Wednesday 50,000 bottles of water had been diverted to the city from neighboring areas.

The city's environment protection bureau on Wednesday morning reported that the content of manganese per liter sampled at the Fujiang River was 1.888 milligram, and that of ammonia and nitrogen was 3.349 milligrams, compared with a state-allowed level of 0.1 milligram and 0.5 milligrams, respectively.

"The pollutant levels are going down as evident from Tuesday's sampling," the bureau said.

In Songpan, where the mine residue leaked, repairs of the dam are under way. The dam was damaged by several landslides that occurred nearby after consecutive downpours pounded the region from last Thursday.

The accidents also damaged residential roads and houses, which forced 272 people to evacuate.