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Sustainable Development and Management of Water Resources in China. Yongqin David Chen Department of Geography and Resource Management The Chinese University of Hong Kong Shatin, NT, Hong Kong Tel: 2609-6539 Fax: 2603-5006 Email: ydavidchen@cuhk.edu.hk. World Water
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Sustainable Development and Management of Water Resources in China Yongqin David Chen Department of Geography and Resource Management The Chinese University of Hong Kong Shatin, NT, Hong Kong Tel: 2609-6539 Fax: 2603-5006 Email: ydavidchen@cuhk.edu.hk
World Water Development Report
今年3月22日是第十一屆“世界水日”,3月22-28日是第十六屆“中國水周”。聯合國確定今年“世界水日”的主題是“未來之水”。今年3月22日是第十一屆“世界水日”,3月22-28日是第十六屆“中國水周”。聯合國確定今年“世界水日”的主題是“未來之水”。 水利部办公厅文件 (办政法〔2003〕23号)
Presentation Outline • Spatial and temporal characteristics of water resources in China • Water problems and challenges • Mega water resources projects in the new millennium
Why does the Yangtze River have flooding almost every year? Why does the Yellow River dry up in the middle and lower reaches in sequential years? Why has the groundwater table in the northern plain been dropping to a lower and lower level? Why have Liaohe, Haihe and Huihe almost become “sewage drainage channels”? Why does the fisheries suffer from red tides so often in the Pearl River Estuary? Why have the lakes on the Qinhai-Xizang Plateau been disappearing?
Relatively large total but small per-capita amount • Total annual renewable water resources: 2812.4 billion m3 (streamflow 2711.5 Bm3, groundwater 828.8 Bm3, duplication subtracted) • Total amount - No. 6 after Brazil, Russian Federation, Canada, US, Indonesia in the world • Per-capita amount - 2200 m3, only about 1/4 of the world average, ranked 109 in 149 countries and one of the 13 countries in severe shortage of water resources • Water per unit area of farmland - 1888 m3/mu, about 80% of the world’s average
Highly uneven temporal and spatial distribution • Monsoon-dominated climate causes very distinctive wet (Apr - Sep) and dry (Oct - Mar) seasons in a Water Year • Seasonal variation of streamflow: 60% from April to July in the South and over 80% from June to September in the North • Interannual variation of streamflow: ratio of maximum over minimum greater 10 in the North and less than 5 in the South • From humid to arid: a gradient from SE to NW
Spatial distribution of water resources does not match with that of population, farmland and mineral resources
Water problems and challenges • Flood and waterlogging hazards - too much water • Droughts and shortage of water - too little water • Water pollution and degradation of aquatic ecosystems - too dirty the water
In the 2155 years from 206 B.C. to 1949, there were 1092 large-scale flood events and 1056 major droughts, i.e., one flood and one drought every two years on the average. • 1/3 of farmland and 2/3 of cities are under the threats of floods. Flood prevention standards are still low and therefore the economic lose caused by floods are enormous (800 billion yuan or 1/5 of the revenue from 1993 to 1997) • From 1949 to 1993, drought was the natural hazard that caused the biggest damages to agriculture nationwide. • More than 300 of China’s 600 cities experience water shortages totaling about 6 billion m3 a year and causing 120 billion yuan a year in lost industrial output.
Three Types of Water Shortage • Water scarcity - northern and northwestern China • Lack of engineering works and water supply systems - southwestern China • Water quality constraints - most common in southern China
Streamflow dry-up episodes in the lower reach of the Yellow River • At the Lijin station, the dry-up episodes occurred in 20 years of the 26 years from 1972 to 1997, i.e., averagely 3 out of every 4 years. • The length of dry-up reaches and number of days have been increasing over the past three decades. • Before 1990, the dry-up episodes occurred mainly in early summer (May, June and July). Since the 1990s, the river dried up for varying numbers of days in almost every month. Human activities have been the key causes of dry-up events.
Temporal coincidence of rainfall and warm temperature • Advantage: beneficial to the growth of plants • Disadvantage: large demand for irrigation in winter and especially in spring during and immediately after sowing
Water quality of major rivers is generally better in the south than in the north because of the differences in assimilative capacities of waterbodies and wastewater-runoff ratios. • By 1995 industrial water pollution in the Huai River Basin was nearly disaster level, prompting the central government to adopt drastic measures to control wastewater discharges along the river. • Urban bodies of water are among the most polluted because they receive large amounts of untreated industrial and municipal wastewater. • Urban sections of rivers are polluted mainly by organic matter. Major pollution includes petroleum, COD/BOD, ammonia nitrogen, volatile phenols, and mercury.
Mega water resources projects in the new millennium • Quantity and quality of water are potentially renewable resources or resources with limited renewability. • China will continue to be a country in water shortage, especially as its population continues to grow. The per-capita amount of water will be only 1760 m3 in 2030 when the population will reach and hopefully stabilize at 1.6 billion. • Engineering and non-engineering measures to prevent floods and droughts, as well as to improve water environment
Three Gorges Dam Project • Location: Sandouping, Yichang, Hubei province • Dam: 1,600 m long, 185 m high, normal water level 135 m by 2003 and 175 m by 2009 • Reservoir: 600 km long, inundate 632 km2, flood control storage of 22.15 billion cubic meter • Expected investment: 203.9 billion renminbi (US$24.65 billion) • Number of migrants: 1.13 million • Installed power generation capacity: 18.2 million kilowatts
Three Gorges Dam Project (cont’d) • Construction timetable: • 1993-1997: The Yangtze River was diverted in November 1997 • 1998-2003: The first batch of generators will begin to generate power in 2003 and a permanent ship lock is scheduled to open for navigation the same year. • 2004-2009: The entire project is to be completed by 2009 when all 26 generators will be able to generate power. • Fund sources: • The Three Gorges Dam Construction Fund • Revenue from Gezhouba Power Plant • Policy loans from the China Development Bank • Loans from domestic and foreign commercial banks • Corporate bonds
Three Major Functions of TGD Project • Flood control – increase flood control capability from 10-year to 100-year event • Power generation – one-nineth of national total electricity • Improved navigation – fleets of 10,000 tons can go to Chongqing … China's most ambitious construction project since the Great Wall.
Arguments in favor of and against the TGD Cost • The dam is within budget, and updating the transmission grid will increase demand for its electricity and allow the dam to pay for itself. • The dam will far exceed the official cost estimate, and the investment will be unrecoverable as cheaper power sources become available and lure away ratepayers. Flood control • The huge flood storage capacity will lessen the frequency of major floods. The risk that the dam will increase flooding is remote. • Siltation will decrease flood storage capacity, the dam will not prevent floods on tributaries, and more effective flood control solutions are available.
Reduction in the lake storage of flood water - total area of lakes in the Jiang Han region has decreased from 3915 km2 to 2623 km2 from 1954 to 1995. • The Dong Ting Lake, the largest freshwater lake in China in the 1950s, has lost over 40% of its area and become the second largest freshwater lake (after the Po Yang Lake). Reduction of storage volume of the Dong Ting Lake
Power generation • The alternatives are not viable yet and there is a huge potential demand for the relatively cheap hydroelectricity. • Technological advancements have made hydrodams obsolete, and a decentralized energy market will allow ratepayers to switch to cheaper, cleaner power supplies.
Resettlement • 15 million people downstream will be better off due to electricity and flood control. • Relocated people are worse off than before and their human rights are being violated.
Environment • Hydroelectric power is cleaner than coal burning and safer than nuclear plants, and steps will be taken to protect the environment. • Water pollution and deforestation will increase, the coastline will be eroded and the altered ecosystem will further endanger many species. Navigation • Shipping will become faster, cheaper and safer as the rapid waters are tamed and ship locks are installed. • Heavy siltation will clog ports within a few years and negate improvements to navigation.
Local culture and natural beauty • Many historical relics are being moved, and the scenery will not change that much. • The reservoir will flood many historical sites and ruin the legendary scenery of the gorges and the local tourism industry.
西线工程在最高一级的青藏高原上,地形上可以控制整个西北和华北,因长江上游水量有限,只能为黄河上中游的西北地区和华北部分地区补水。西线工程在最高一级的青藏高原上,地形上可以控制整个西北和华北,因长江上游水量有限,只能为黄河上中游的西北地区和华北部分地区补水。 中线工程从第三阶梯西侧通过,从长江中游及其支流汉江引水,可自流供水给黄淮海平原大部分地区。 东线工程位于第三阶梯东部,因地势低需抽水北送。 东线、中线、西线三项工程的年调水总规模约380~480亿m3,相当于黄淮海平原和西北地区增加一条黄河的水量,可基本缓解我国北方地区水资源严重短缺状况,这个总体布局是合理的。
Non-engineering Measures • Water resources and environmental legislation, regulation and management • Water and climate simulation, forecasting and decision-support systems • Integrated watershed management for land use planning and ecosystem protection • Financial investment, insurance protection and education • Research and advancement in hydrological sciences
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