CHINA admitted yesterday that toxic contamination from a petrochemical plant accident was the reason for cutting the water supply to millions of people in a frozen northern city. The pollution of a major river was 100 times above safety levels, officials said.

Frightened residents of Harbin jammed airports and stations, trying to escape the city after officials cut off the water for at least four days from midnight on Tuesday. The authorities put on extra flights out of the city. One factory manager said: “Everyone wants to leave Harbin and it is very difficult to buy tickets.”

Supermarket shelves in the city were swept bare of bottled water and soft drinks as panicking citizens stocked up for the shortage. Schools cancelled classes until next week.

The Government finally disclosed the reason for halting the water supply to 3.8 million of the 9 million residents of the municipality to try to stop rumours that fuelled the panic buying. Du Yuxin, the Harbin Communist Party Secretary, said: “The recent explosion of two benzene processing towers at PetroChina’s Jilin Petroleum and Chemical Company could end up polluting waters in the Songhua river.”

Confusion remained over when water supplies would restart after officials withdrew a notice announcing that the stoppage would last four days. The State Environmental Protection Administration said that water in some parts of the Songhua river had recorded benzene more than 100 times above safety levels. Residents reported seeing dead fish on the river’s banks. The Songhua river flows north from Jilin province, through Harbin, the capital of Heilongjiang province, and into Russia.

Contamination was estimated at 29 times safety levels as the polluted water approached Harbin. The Foreign Ministry said that China had notified Russia of the problem on Tuesday and the two countries were in frequent contact.

Officials estimated that the worst of the pollution would flow through Harbin in the early hours of this morning. Fifteen hospitals in the city have been put on alert to handle contamination cases.

Benzene, a toxic industrial solvent and component of petrol, can be lethal in high doses, the US National Library of Medicine’s website says.

More than 16,000 tonnes of bottled water was being transported to Harbin from nearby cities. Residents had filled baths and buckets and many said they had enough water for four days, but they were worried that they could run out if the stoppage lasted longer. One restaurant owner said: “Today is only the first day and I have no confidence that the water supply will restart in four days. The Government did not tell us the real reason so there are lots of rumours and fears. I hope the Government will just tell us what they know.”

Companies that supply steam heat to buildings have been ordered to ensure that they have adequate water supplies from wells. Harbin is one of the coldest places in China, with overnight temperatures this week of -12C (10F).

The ordeal of Harbin’s residents highlights the precarious state of China’s water supplies. The country’s 1.3 billion people and the factories and farms of its booming economy compete for scarce supplies, and the Government says that all major rivers are dangerously polluted.

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