Last Thursday people in Songjiang district reported seeing dead pigs floating in the upper reaches of the Huangpu River. By Tuesday, nearly 6,000 pig carcasses had been salvaged from the river and salvaging was continuing at the time of going to press.

"This wasn't the first time that I had seen dead pigs floating in the river. They have done this for years. But never like this - so many and all at once. It's disgusting," a man surnamed Huang who lives near the river told the Global Times.

Huang said he first saw pig carcasses in Hengliaojing Creek in the district. He took pictures of them and called the local authorities. He also posted the pictures on Sina Weibo, China's twitter-like social media outlet, which soon attracted public and media attention.

Authority spokesmen said that judging from the levels of decomposition, some of the pigs might have been in the river for more than a month. "According to the ear tags on the pigs, they were dumped in the river in Jiaxing, Zhejiang Province, where pig farming is a major industry," Xu Rong, the director of the Shanghai Songjiang District Environmental Protection Bureau, told the Global Times.

Safety concerns

The incident has aroused concerns about the safety of the city's water supply after an animal disease control center laboratory with the Shanghai Municipal Agricultural Commission announced on Monday that tests on the pig carcasses had revealed the presence of porcine circovirus, a virus that affects pigs but not humans.

The area where the carcasses were found is close to a water resource for millions of people living in the city's Jinshan, Songjiang, Fengxian and Minhang districts. Although the city water authority said tap water in the area had passed quality tests, it had increased the frequency of testing to once every four hours to reassure the public. But some experts say there is still a possibility that there is a risk.

Yang Haizhen is a professor of water resources study at Tongji University. He told the Global Times: "The problem is who should be held responsible for such large-scale dumping of carcasses and how it can be prevented from happening again? And what if the pigs were carrying other diseases that can be transmitted to humans?"

Under the Animal Epidemic Prevention Law, farmers have to dispose of dead animals properly. When an animal dies of an unexplained cause, a farmer should contact a veterinarian to ensure that the cause of death is not a contagious disease. Animals that die from anthrax cannot be buried but must be burned to prevent soil contamination. Investigations into the Huangpu River incident are continuing.

Response questioned

Although the authorities stated that the water was safe, the public has been expressing doubt and questioning the official response.

"Did the government know about this problem a long time ago? Why they didn't take action in time to prevent it worsening until we reported it?" asked Huang from Songjiang district.

This was not the first time that Songjiang district tap water safety had been threatened this year. One month ago a Songjiang district factory making Apple products was found to be discharging industrial waste into local rivers.

On February 10, residents reported that a local river had turned white for several days in a row. The Shanghai Songjiang District Environmental Protection Bureau investigated and confirmed that the Shanghai RiTeng Computer Accessory Co factory was the source of the pollution and ordered it to stop operating until it could meet the environmental standards required.

When the Global Times approached the company, Zhong Yuanwen, the assistant general manager, explained that the incident occurred accidentally when the factory discharged waste water into the rainwater drains instead of the sewerage system as they were cleaning equipment during the Spring Festival.

Although the company was fined the maximum 200,000 yuan ($32,174) for the incident, it seems it could not guarantee that similar accidents would not happen again.

In January 2011, a report published by five non-governmental environmental protection organizations named 27 Apple product suppliers across the country as having serious environmental issues. Many of them had a bad record like the factory in Songjiang.

"We called it the 'poison Apple' because it threatened people's health. As one of the best-known companies in the world, we wonder if Apple is aware of the pollution that these factories have created or if it just chose not to push its suppliers to solve these problems," said Ma Jun, the director of the Institute of Public and Environmental Affairs, one of the five participating NGOs.

Another incident

In January there was another serious water pollution incident on the border of Songjiang and Jinshan districts. This interrupted the water supply for some 30,000 people in the area. 

According to the Oriental Morning Post, the incident occurred when a truck delivering hazardous materials illegally discharged waste into a major river on January 10. This caused the levels of the harmful chemical, styrene, to exceed the permissible level. The toxic waste went on to pollute a water source and caused the suspension of supplies from two water treatment plants for two days.  

The incident saw residents stampeding to supermarkets to buy bottled water. Within half a day there was no bottled water available in the area. Schools were closed and fire trucks were dispatched to deliver water to some villages. The crisis lasted two days while the water plants purified their pipes to ensure all pollutants had been removed.

Although Shanghai had started to shift its major water resources from the Huangpu River to the Yangtze River after the Qingcaosha Reservoir officially opened in 2011, pollution concerns remain. Nowadays 30 percent of the city's drinking water comes from the Huangpu River.

"The recent incidents show we haven't yet built an effective and comprehensive monitoring and early warning system to protect the water resources in Shanghai, especially when it involves incidents in other provinces," Dai Xingyi, a professor from the Urban Environment Management Center at Fudan University, told the Global Times.

Dai said the incidents revealed loopholes in the current monitoring system and suggested the authorities should learn from these lessons and immediately work to improve regional cooperation against pollution. 

"It's a joint project. No one can protect himself alone from pollution. No matter how much you spend on protection, this will be pointless if there is pollution in the upper reaches," said Xu Xuehong, the deputy director of the Water Resources Protection Bureau for the Taihu Basin. She admitted that an effective water protection system among cities in the Yangtze River Delta was yet to be implemented.

"To prevent similar water accidents in Shanghai, businesses, government, and individuals should all increase environmental protection awareness and comprehensive laws should be introduced to crack down on any violations," said Sun Congjun, a senior researcher from the Shanghai Academy of Environmental Sciences.

Factory discharges

In a Global Times report in 2011, Professor Chen Zhenlou from the School of Resources and Environment from East China Normal University said the biggest threat for Shanghai's water resources was pollution from the upper reaches of the Yangtze River, most of which was caused by illegal factory discharges and domestic sewage.

Chen said that even though Shanghai has done a fine job of protecting and managing the Qingcaosha Reservoir, pollution from upstream is like a sword of Damocles threatening the water supplies for the city.

A Ministry of Environmental Protection survey in December, 2010, showed that 81 percent of some 7,555 chemical and petrochemical industry projects under construction were being built beside rivers or in densely-populated areas. Forty-five percent of these projects were considered high risks.

According to the survey, along the Yangtze River there were some 400,000 chemical plants, five major iron and steel plants and seven major refineries. It pointed out that the threat from the chemical industry was especially obvious in the lower reaches of the Yangtze River. Along the Yangtze River from Nanjing to Shanghai, there were eight major chemical industrial zones which were all "time bombs" for Shanghai's water.

"The recent incidents in the Huangpu River which affected people's everyday lives should make us aware of the problems before it is too late. No one can promise this will not happen again. If this happened in the Yangtze River, which is now the major drinking water resource for Shanghai, it could lead to a disaster," Chen said.

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