Wednesday, November 21, 2012

Fresh water environment in China: an overall grim situation with apparent slight amelioration on lakes from a poorly documented report

Figure 1 : Siberian and White-naped Cranes near Poyang Lake from

Main information discussed in this Post are issued from the 2011 State of the Environment Report (SOE) published on 25th of May 2012 by the Ministry of Environmental Protection. The 2011 SOE is less detailed as the previous 2009 & 2010  issues and is not published in English. This makes comparisons more arduous.
Water resource has always been a problem in China particularly in the region north from the Yangtze River where only 19.1% of  resource from rain is falling. In the past 50 years, water overexploitation has almost dried up the Yellow River's valley. In 1997, the lower Yellow River did not flow during 230 days. Increased erosion and sedimentation, especially on the Loess Plateau, have made the river much less navigable.

Figure 2 : China main rivers 
Continuous emissions from manufacturing industries and industrial spill hazards are the largest contributor to lowered drinking water quality across the People’s Republic; introduction of poorly treated sewage and extensive use of agricultural fertilizers and pesticides have proven to be major contributors as well.
These water quality issues coupled with seasonal scarcity of water may spark endemic water shortages, which frequently affect millions of people.

Main river systems

China uses a six-grade classification scheme for water quality. Grade I & II are the best. Water no worse than grade III can be used for drinking, although sometimes treatment is required. Grade V can be used for irrigation. Water less than grade V cannot be used for irrigation. Nevertheless according to criteria used by the UN Environment Program, both grade V and less than V are unfit for drinking, aquaculture, industrial use and even agriculture.

The 2011 State of the Environment Report (SOE) underlines that the quality of specific rivers systems is deteriorating from South to North as follows (see Figure 3):
  • The Pearl River and the Yangtze River systems have "good water quality";
  • The Huaihe River, and the Yellow River systems have “ poor water quality";
  • Both the Haihe River flowing through Beijing and Tianjin and the Liaohe River systems are "badly polluted".
  • The Songhua River is "moderately polluted".
In order to appreciate variation from the previous 2 years we have dismissed additional river systems   (Zhejiang and Fujia, Southwest and Inland river systems). Figures 3 & 4 concentrate on the major systems which were already in the 2009-2010 review.
Figure 3 : Quality grading of the seven major river systems in 2011
The Yellow River Conservancy Committee, which surveyed more than 8,384 miles of the river in 2007, said 33.8% of the river system registered worse than grade V. The report said waste and sewage discharged into the system totaled 4.29 bil tons. Industry and manufacturing provided 70% of the discharge into the river, with households accounting for 23% and just over 6% coming from other sources.
The 2005 Jilin chemical plant explosions in Jilin City caused a large discharge of nitrobenzene into the Songhua River and the entire water supply to Harbin city  was cut off for five days though it was only after 3 days that officials admitted that a severe pollution incident was the reason for the cutoff.

Figure 4 : Variation of major river system water overall quality from 2009 to 2011

As it can be seen on Figure 4, for all major river systems across around 400 river sections under national monitoring, overall river quality does not really improve over the last 3 years. 

It should be noted that grade V is not documented in the current SOE report and was around 25% of Grade IV-V in 2009-2010 and even more for the Yellow River. 

As a result  we can presume under UN Environment criteria that grade V or less unfit even for agriculture and industrial use which registered  around 33% in 2007 are still currently around 22-24% which is a very grim water quality.

Lakes and fresh water reservoirs

Among the 26 key lakes and reservoirs under national monitoring program, quality ranged as shown in Figure 5. Apparently the quality has improved from the previous 2009-2010 years with a two fold increase of grade I-III.  But it should be noted that no detailed documentation was provided in 2011 on each lake or reservoir quality as it was the case in the previous two years. This lack of detailed information- as data are improving much- is extremely worrying.

The main pollution indicators were total phosphorus, and chemical oxygen demand (total Nitrogen does not participate in water quality evaluation).
Figure 5 : Overall quality grading of major lakes and reservoirs 2009-2010-2011

Addition of nutrients such as nitrogen and phosphorus through fertilizer or sewage discharges are the determinant of the eutrophic state of a reservoir. The increase of nutrients causes the proliferation of plants and living organisms such as algae or phytoplankton

Lakes are usually classified as being in one of three possible classes: 
  • oligotrophic  (little or no aquatic vegetation) , 
  • mesotrophic (commonly clear water)
  • eutrophic (large quantities of organisms, including algal blooms)  

Figure 6:  Trophic state index (TSI) of major lakes and reservoirs in 2011

Among the 26 lakes and reservoirs (see TSI in Figures 6 & 7) a majority of lakes or reservoirs are under eutrophic state: 8-11% under heavy (HE) or intermediate (IE) and 42-46% under slight (SE) eutrophic state. Only 46% are posting mesotrophic (ME) level in 2010-2011 in reduction from 2009.  Currently only a minority of lake have clear water with little or no aquatic vegetation.

Figure 7 : Overall TSI of major lakes and reservoirs 2009-2011

Compared during the previous years the TSI shows a variation among the monitored water bodies:
  • Reduction of eutrophic state: Dianchi Lake improved from heawy  to intermediate,  Donghu  Lake from Intermediate to slight  eutrophication. 
  • Raising of state: from slight to intermediate both Yuqiao  and Songhua reservoirs.
There have been a high number of river pollution incidents in recent years in China, such as drinking water source pollution by algae in the Taihu Lake  in May 2007. It was reported that a "bloom of blue-green algae that gave off a rotten smell" shutting off the main water supply to 5.8 mil people. By October 2007 the Chinese government told it had ordered 1,300 factories around the lake to shut down. However, Wu Lihong, one of the leading environmentalists alleged in 2010 that not a single factory was closed. Jiangsu province planned to clean up the lake and chaired by Wen Jiabao the State Council set a target to clean Taihu lake  by 2012.  However, in 2010 The Economist reported that a fresh pollution outbreak had occurred, and that Wu, released from prison in April, was claiming that the government was trying to suppress news of it, all the while switching to other supplies in place of lake water.

Ground water quality in Cities

Ground water as opposed to surface water (river and lakes) is located beneath the earth in aquifer. Ground water in cities is more affected by pollution than China’s rivers and lakes.

In 2010-2011, 182-200 cities across the country had been carrying out a ground water quality monitoring on a total of 4100-4700 points. The drink water classification is organized with the following 5 levels: excellent, good, almost good (to a better level…), poor, very poor. 

National groundwater quality situation is stable at a very alarming level with a majority of monitored points which have poor or very poor levels: together 57% on 2010 and 55% on 2011.  
Water quality is excellent - good – almost good (to be better…) only for 43% in 2010 and 45% in 2011. The odd level almost good (to be better…) is around 5% on both years.

Deteriorated water quality in the city are mainly concentrated in the north, northeast and northwest regions.

Figure 8 : Quality level of underground water in Chinese cities

Chinese environmental activist and journalist Ma Jun warned in 2006 "In the north, due to the drying up of the surface water, the underground water has been over-extracted. The water shortage in the north could have drastic affects because almost half of China’s population lives on only 15 percent of its water. The situation is not sustainable. Though the south has abundant water, there is a lack of clean water due to serious water pollution. Even water-abundant deltas like the Yangtze and the Pearl River suffer from water shortage”.
According to an article in the Guardian, in 2005, Pan Yue, deputy director of the state environment protection agency, warned that economic growth was unsustainable due to the water problems. In 2004 the World Bank warned that the scarcity of the resource would lead to "a fight between rural interests, urban interests and industrial interests on who gets water in China."

Water conservation and transfer projects

Three Gorge 22,500MW power dam, by reducing coal consumption, increasing Yangtze's barge capacity avoids tons of Green house gas. An important function of the dam is also to control flooding major problem of Yangtze River and thus increase the water available during the dry season. The reservoir's flood storage capacity is 22 km3 which is almost 50% of all major and key lakes discussed above. 

But the mere size of the reservoir -660 km length x1.12 km width- implies a huge ecological and human cost:  

  • The land in the area is experiencing erosion, absence of silt downstream will cause riverbanks to become more vulnerable to flooding including Wuhan, Nanjing & Shanghai more than 1,600 km away. 
  • Much of this Yangtze sediment is now settling in the dam instead of flowing downstream; less benthic sediment downstream will cause biological damage and reduce aquatic biodiversity.
  • The region is home to 6,388 species of plants of which 57% are endangered. Around  361 different fish species are living in the Yangtze River basin accounting for 27% of all endangered freshwater fish species in China. The dam contributed to functional extinction of the Baiji Yangtze river dolphin. From the 3,000 to 4,000 remaining critically endangered Siberian Cranes, a large number currently spend the winter in wetlands destroyed by the Three Gorges Dam. As of June 2008, China relocated 1.24 mil residents about 1.5% of the province and Chongqing Municipality population on which about 140,000 were relocated to other provinces. The 600km long reservoir flooded some 1,300 archaeological sites and altered the appearance of the Three Gorges as the water level rose over 91 m; heritage relics are being moved to higher ground as they are uncovered, but the flooding inevitably covered undiscovered relics. Some sites could not be moved because of their location, size, or design.

As concerns the ecological cost only, the question is whether the reduction of footprint (less CO2 released and more fresh water available) resulting from Three Gorge Dam are greater than the cost in biocapacity reduction resulting  from endangered wetlands, biological damage, plant and animal wildlife extinction. The only fact that the cost of the loss of ecological capital that can never be replaced is beyong assessment provides some clue.

South North Water Transfer Project (SNWTP): Large-scale water transfers have long been discussed by Chinese authorities as a solution to the country's water shortage. The South-North Water Transfer Project- the Eastern Route or Grand Canal revamping-  is being developed primarily to divert water from the Yangtze River into the Yellow River and Beijing.
The development or diversion of major rivers originating from China but flowing mostly across Chinese boundaries, such as the Brahmaputra River and the Mekong River, could be a source of tension with Vietnam South North Water Transfer Project and Thailand. In a book titled "Tibet's Waters Will Save China" a group of Chinese ex-officials have championed the northward rerouting of the waters of the Brahmaputra as an important lifeline for China in a future phase of South-North Water Transfer Project. Such a diversion could fuel tension with India and Bangladesh, if no prior agreement would be reached on sharing the river's water.