Starting from noon today, the city's water supply will be cut off for four days, said a statement issued by the municipal government of the capital of Northeast China's Heilongjiang Province.
It is the first time that water supply will be cut off citywide for so long.
"To ensure the safety of water, the municipal government has decided to thoroughly check the city's water supply system and cut off supply temporarily," it said.
The lack of details led to swirling rumours that the water in Songhua River, which supplies the city, was contaminated as a result of a chemical-plant blast on November 13.
The common refrain was that the explosion at Jilin city of neighbouring Jilin Province on the upper reaches of Songhua River may have caused a leakage of poisonous substances into the river as it is only a few hundred metres away from the plant. Harbin is located at the middle reaches of the river.
But an official with the Harbin municipal government, who did not want to be named, dismissed the assumption as "just a rumour."
Harbin Water Supply Company refused to comment but sources at the municipal environment bureau said that there was nothing abnormal with the quality of water in the river.
In corroboration, Jilin said that the local environment bureau found that the water quality was barely affected after the blast.
Water supply to some parts of Harbin was already cut off at around 4 pm yesterday and anxious residents thronged supermarkets and shops to buy whatever they could lay their hands on.
Bottled mineral water, beverages, and even milk were sold out in big supermarkets such as WalMart and Carrefour.
"People started to pour in from 1 pm," said Zhang Ping, an employee at Century Mart, a chain supermarket. "By 3 or 4 pm, all the drinks were sold out," she said.
"I heard the news from a friend, so I hurried here," said Zhang Xiaoming, a saleswoman, who was carrying three boxes of bottled water in her cart. "But I don't think there are enough."
Prices of bottled water have risen sharply. For example, the wholesale price for Chunzhongchun, a local brand, has doubled from 0.5 yuan (6 US cents) to 1 yuan (12 US cents) a bottle.
The municipal government has ordered all bathhouses and car-wash facilities to stop operations during the four days.
It also ordered the city's administration of industry and commerce, the price bureau and police to strengthen surveillance over the market and maintain social order.
