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
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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 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
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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.
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).
- 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
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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.
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:
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.
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