Harnessing flow of water is the art of life (WANG Shucheng)
Author: 系统管理员Source: Updated: 2009-06-03


Floods, water shortage and droughts, and deterioration in the quality of water are the major hurdles on the road to China's sustainable development. Water shortage is by far the biggest of the hurdles. Water safety has become increasingly important because of climate change and freaky weather.

Though China's total water resource is 2,800 billion cubic meters, making it 6th in the world, its per capita availability of water is only 2,200 cu m, about 30 percent of the global average. And confounding matters is the uneven distribution of water across the country.

The southern part of the country has more water reserve but is home to a smaller percentage of the population, cultivable land and mineral resources. In contrast, the northern part has less water but a larger population, more arable land and mineral resources. The Yangtze River basin and its southern parts account for 36.5 percent of the national territory, but have 81 percent of nation's water resources. On the other hand, the Huai River basin and its northern parts account for 63.5 percent of the country's territory but have only 19 percent of the country's water resources.

Rainfall is unevenly distributed in the country because of the monsoon. Rainfall during the four monsoon months accounts for about 70 percent of total precipitation in the country. But two-thirds of that is lost in floods. Besides, precipitation varies dramatically from year to year.

Climate change and extensive economic development have changed the structure of water resources. The latest water resources evaluation shows that the precipitation of the basins of Yellow, Huai, Hai and Liao rivers has decreased by 6 percent on average compared with hydrological data collected between 1980-2000 and 1956-1979. Surface water resources of the four river basins have fallen by 17 percent on average, with surface water of the Hai River basin dropping by 41 percent.

Water shortfall in the country is 40 billion cu m a year. Two-thirds of China's cities are facing shortage of various degrees, and an average 230 million mu of irrigated area is affected by drought every year.

Low per capita availability of water and its uneven distribution has made China vulnerable to frequent floods and droughts. These cause more water shortage and pollution and confound the problem of a fragile environment.

Human beings' demand for water is different during different periods of economic and social development. Therefore, water development needs to be continued to satisfy the changing demands of humans. Their demand can be generally divided into five categories: safe drinking water, water supply safety, flood control safety, food security and environmental safety.

Safe drinking water: In September 2000, the UN Millennium Development Goals (UNMDG) proposed to reduce by half the population of people without sustainable access to safe drinking water by 2015.

China made a commitment to fulfill the target, and implemented the Plan of Drinking Water Safety Project in Rural Areas. In 2000, there were 379 million people without sustainable access to safe drinking water in the country's rural areas. From 2001 to 2008, 65.6 billion yuan was allocated for the project, with 35.5 billion yuan coming from the central government and 30.1 billion yuan from local governments. The project helped 175.66 million people get safe drinking water.

It looks certain that China will meet the UNMDG goal six years before schedule (i.e. in 2009). The government is determined, too, to provide safe drinking water to all rural residents by 2013.

Flood control safety: The devastating floods of 1998 taught the government two important things. The first was that dikes and embankments have to be built along the Yangtze, Huai, Hai, Songhua and Neng rivers to control floods. Apart from that, the Three Georges project has reduced the possibility of a flood in the Jingjiang River belt to once in 100 years. The possibility of a flood in the area below the Xiaolangdi Reservoir in the Yellow River basin is even less: once in 1,000 years. Also, 19 key projects along the Huai River have been completed on schedule, building a flood control system in the river's basin, which is regarded as a milestone.

The second thing the 1998 floods taught was that the threat posed by hazardous reservoirs had to be eliminated by reinforcing them.

In 2000, the first-phase of the project with 1,346 reservoirs was initiated. Three years later, the second-phase with 2,300 reservoirs was started. And in 2006, a special plan added another 6,240 hazardous reservoirs to the project. The central government subsidized the project, and according to plan, reinforcement of mid- and large-sized hazardous reservoirs and some highly hazardous small reservoirs will be completed by 2010.

 
 
But the overall flood control capacity is still poor and throws up two outstanding issues. First, some tributaries of big rivers have a relatively poor capacity of withstanding floods because of their small flood retention basins. Plus, the flood control standard is relatively poor in most of the small- and mid-sized rivers. Second, extreme weather caused by climate change is becoming more common, as a result torrential rain and cloudbursts are causing more disasters and accidents.

To face such emergencies and disasters, we have to make better preparations.

Food security: The country's grain production has increased for five consecutive years. It reached a record 528.50 million tons in 2008. Food security has always been an important part of China's policy because of its large population. It is important, too, for stable development of the economy and society.

But farmers still depend on the weather gods for their crops. We have to add more muscle to our drought relief mechanism and provide irrigated water to more areas to ensure food security.

The farming sector accounts for 64 percent of the total water consumption in China. The imbalance between demand and supply for water has become more evident with population increase, shrinking of arable land and water shortage.

Irrigation and drainage facilities have been built at a fast pace since the establishment of the People's Republic of China. The area of irrigated land has effectively reached 625 million hectares, accounting for 46 percent of the total arable land. And irrigated areas equipped with water-saving facilities have reached 387 million hectares, or 62 percent of the total.

In the 30 years since the reform and opening up, water use coefficient of irrigated agriculture has increased from 0.35 to 0.46. Taking the growth of water consumption as zero, grain yield has increased by nearly 50 percent. By 2030, China's population will reach 1.6 billion, so the water use coefficient of irrigated agriculture has to rise to 0.55 (it's about 0.70 in developed countries) to ensure food security in the future.

Here, I would like to emphasize that more attention should be paid - especially in the major grain production areas- to improving drought relief in natural disaster prevention and control programs, and drought relief should be made the top priority in waterworks construction in rural areas.

Water supply safety: China has scarce water resources. The per capita water availability of 2,200 cubic m will drop to 1,700 cubic m in 2030 when the population reaches 1.6 billion. That figure would be lower than the globally accepted stress line of 1,800 cu m. The country has a water shortfall of 40 billion cu m in a normal year. More than 400 of its cities are facing water shortage, with 110 of them facing a severe shortfall.

Three measures can ensure water supply security: water conservation, new water projects and unconventional sources of water.

We need to build a society that conserves water and increases the efficiency level of its use. Great achievements have been made in water conservation in recent years. According to comparable price in 2005, water consumption per 10,000 yuan GDP decreased from 2,489 cu m in the 1980s to 254 cu m in 2007, water consumption per 10,000 yuan industrial value-added decreased, too, from 828 cu m to 142 cu m. By 2020, water consumption per 10,000 yuan GDP will fall further, to less than 125 cu m, and water consumption per 10,000 yuan industrial value-added will drop below 65 cu m - nearly level with that of developed countries.

New water projects are being constructed for big cities such as Harbin, Changchun, Shenyang, Dalian and Xi'an. And the completion of middle and eastern route schemes of South-North Water Diversion Project will safeguard the water supply for 44 cities, including Beijing and Tianjin.

Unconventional water sources are being tapped. For example, experiments are continuing on the use of recycled and storm water, as well as on desalinization of seawater.


Source: China Daily
 
The author is Wang Shucheng, former Minister of Water Resources. The article is first part of his keynote speech at an international symposium on water security held by China Institute for International Strategic Studies.


 

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