Shanghai's troubled waters

By Liu Dong Source:Global Times Published: 2011-12-5 16:16:00

Qingcaosha reservoir sits at the mouth of the Yangtze River on Shanghai's Changxing Island. Photo: CFP

One of the highlights of the year for 65-year-old Shanghai man Ruan Kangcheng was turning on the tap and being able to drink water that was cleaner and tastier than ever before.

"Now whenever I have a shower, the water in the tub is so much cleaner," said Ruan, who has been living in downtown Xuhui district for the past half century.

What changed for Ruan and many other Shanghai residents was the introduction of the Qingcaosha raw water resource project that sources water from the Yangtze River. It officially came on line in December 2010, after 15 years of planning and three years of construction.

Although Shanghai is located at the mouth of the Yangtze River, it lacks quality fresh water - the city's primary water source, the Huangpu River, has been seriously polluted since the 1980s, according to the Xinhua News Agency. By 2012, the city is expected to be collecting up to 70 percent of its tap water from the Yangtze River to improve its water quality. But it seems the Qingcaosha project will not solve all of the city's water supply problems.

A huge project

The Qingcaosha raw water resource project included building a major water reservoir and connecting pipe lines and pumping stations. The massive 17-billion-yuan ($2.67 billion) 70-square-kilometer facility is found at the mouth of the Yangtze River on Shanghai's Changxing Island. Its reservoir has a storage capacity of 438 million cubic meters of water and from this October has been providing water for nearly half of the city's population. 

"It covers an area almost equal to 10 West Lakes," said Lu Xiaoru, the general manager of the Shanghai Qingcaosha Raw Water Engineering Company, which oversaw the project's construction.

The deputy director of the Shanghai Water Authority, Chen Yuanming, told the Global Times that the water from the Yangtze River was of a much higher quality than that from the Huangpu River.

However doubts about the water quality from the Qingcaosha project have now emerged. According to the Beijing-based Economy & Nation Weekly, the Shanghai Water Authority said that the raw water quality from Qingcaosha reservoir met the class two standard, the national standard for major drinking water supplies. But this ignored two vital measurements: the amounts of nitrogen and phosphorus in the water. These can affect the quality of water as an oversupply of nitrogen and phosphorus artificially causes nutrient growth and thus pollution.

The report said if these two elements were taken into consideration, the water quality from Qingcaosha would fall to a class five level, the lowest possible score according to the environmental quality for surface water standards published by the Ministry of Environmental Protection and the General Administration of Quality Supervision in 2002.

The report said removing some of the "less important" indicators to make water quality measurements meet national standards has become a common, if undercover, practice in many Chinese cities.

The chief engineer of the water supply management department at Shanghai Water Authority, Chen Guoguang, said the levels of nitrogen and phosphorus in the Qingcaosha reservoir were respectively 1.40 milligram/liter and 0.08 milligram/liter, both within the class four level.

"But it has not been necessary to check nitrogen and phosphorus levels, which are relevant when the water source is an area like a lake but not when it is a free flowing source like the mouth of the Yangtze River," Chen Guoguang told the Global Times.

A Shanghai Water Authority internal report seen by the Global Times, however, noted that the Qingcaosha reservoir faced problems with high levels of nitrogen and phosphorus, which can cause the growth of harmful algae.

A worker at the Qingcaosha reservoir in Changxing Island told the Global Times that they had been releasing fish to eat the algae and using other chemicals to control algae outbreaks. "So far the situation is under control."

 

A man checks readings in the control room of the Qingcaosha reservoir.
A man checks readings in the control room of the Qingcaosha reservoir.

 

An ongoing problem

The lack of good-quality fresh water has been a problem for the city for a long time. Before the Qingcaosha reservoir was completed in 2010, the water supply changed sources several times.

In 1911, the initial major drinking water resource in Shanghai was Suzhou Creek when the first water works were built in today's Zhabei district. Later, because of the pollution in Suzhou Creek, the water intake was moved to downstream Huangpu River. By 1978, the Huangpu River was also seriously polluted and the intake was moved again and again over the next 20 years along the upper sections of Huangpu River.

Before the establishment of the Qingcaosha reservoir, the city relied on Huangpu River for 70 percent of its water with the other 30 percent coming from the Yangtze River.

But the source of the Huangpu River, Taihu Lake, was also becoming polluted by eutrophication (an oversupply of nitrogen and phosphorus) and this pushed authorities to find a new water supply.

Xu Xuehong, the deputy director of the Water Resources Protection Bureau for the Taihu Basin, told the Global Times that if Shanghai continued to take water from the Huangpu River, the entire river ecosystem would face a crisis.  

Last month, Shanghai's neighbor city, Hangzhou, moved to improve its water supply. Because of growing pollution in the Qiantang River, the current water source for Hangzhou, the city authorities plan to draw water from Qiandao Lake to guarantee a water supply for the city's 8.7 million people.

However the plan has been heavily criticized by experts and citizens for its expense with many arguing that the government should use such a large amount of money to fight pollution rather than to import water from hundreds of kilometers away.

The biggest threat

According to Professor Chen Zhenlou, with the School of Resources and Environment at East China Normal University, the biggest threat for Shanghai's water resources was pollution from the upper reaches of the Yangtze River, mostly caused by illegal factory discharges and domestic sewage.

"Even though Shanghai has done a perfect job in protecting and managing the Qingcaosha reservoir, the pollution coming from the upper stream is like the sword of Damocles threatening water supplies in Shanghai," Chen told the Economy & Nation Weekly.

Chen was not being paranoid. A survey conducted by the Ministry of Environmental Protection in December last year revealed that 81 percent of some 7,555 chemical and petrochemical industry projects under construction were being sited by rivers or in densely-populated areas. Forty-five percent of these projects were considered high risks.

Along the Yangtze River there are some 400,000 chemical plants, five major iron and steel plants and seven major refineries. The threat from the chemical industry is especially obvious in lower reaches of the Yangtze River, according to experts. From Nanjing to Shanghai, eight major chemical industrial zones spread along the banks of the Yangtze River.

"They are time bombs. If anything happens to these chemical factories, it could be a disaster for Shanghai," said Shen Jianhua, a senior researcher with the Shanghai Institute for Biological Sciences.

Officials from Shanghai Water Authority admitted at a government meeting recently that the security measures in place at the Qingcaosha reservoir are probably inadequate in the case of a major pollution threat upstream. Chief engineer Chen Guoguang said that the authority was working hard to improve methods of handling emergencies.

 

A resident in Pudong New Area pours tap water from the Qingcaosha reservoir.
A resident in Pudong New Area pours tap water from the Qingcaosha reservoir.

The last resource

The deputy director of the Shanghai Municipal Engineering Design Institute, Wang Yu, said the authorities should never treat this last water resource for Shanghai lightly.

"Even though the quality of water from the Yangtze River is better than the Huangpu River, it has gone thousands of miles and past hundreds of cities before arriving in Shanghai. It could contain many complex pollutants from all kinds of sources, which are not easily detected and countered. I suggest that all city drinking water undergo deep purification technology, which adds another stage to the purification process and can remove nitrogen and phosphorus and some other trace elements."

Wang added that the city was still using relatively low-quality water compared to other cities along the upper reaches of the Yangtze River. "Improving water quality should always be our goal."

The Water Resources Protection Bureau's Xu Xuehong said that protection of water resources relied not just on one city but on cooperation.

"It's a joint project. No one can protect themselves alone against pollution. No matter how much you spend on protection, it is in vain if there is still pollution in the upper reaches. It is a matter of urgency that we introduce and enforce adequate laws for water pollution," she said. "When the problem with the source is solved, it will be easier to guarantee the safety of our drinking water."


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