Water Conservancy: South-to-North Water Transfer Project
Planning
China possesses the total water resources of 2800 billion m3, ranking the sixth in the world. But in respect of water volume commanded by per capita, its place comes down to the eighty-eighth, that is, the available water for every Chinese people amounts to one fourth of average amount of the world. So China is a country in shortage of water.
China has a much disproportionate distribution of water and soil resources. Changjiang (Yangtze) River Basin and those rivers situated to the south of it yield a runoff accounting for more than 80% of the nation's total, while they have a cultivated land of less than 40% of the nation's total, known as water surplus area. On the contrary, Huanghe (Yellow) River, Huaihe River, Haihe River basins and northwest inland have a half of nationa1total area and 45% of total cultivated land and 36% of the total population, but possess only 12% of the total water resources, as water deficient area. The Northwest and North China have rich land and mineral resources, and are production base of energy, grain, cotton and edible oil, and play an important role in national economy. In particular, Huang-Huai-Hai Plain and Jiaodong Peninsula are areas with dense population, more cultivated land and developed economy. In these areas, poorer water has been a factor restricting economic development, and causes biological environment deteriorated. The problems are awaiting immediate solution through water transferring.
General Layout
Since the earlier study on South-to-North Water Transfers started in the 1950s, the following general layout of South-to-North Water Transfers has been worked out: three water transfer projects, i.e. Western Route Project (WRP) and Middle Route Project (MRP) and Eastern Route Project (ERP) will divert water from upper, middle, and lower reaches of Changjiang River respectively, to meet the developing requirements of Northwest and North China.
The layout is suited to three topographic terraces of the continent of China. Situated in highest Qinghai-Tibet Plateau, WRP can control whole Northwest and North China, but only divert water for Northwest in upper and middle reaches of Huanghe River due to the limited water quantity in the upper reach of Chmgjiang River. Passing the west of the third terrace, MRP will divert water from middle reach of Changjiang River and its tributary, Hanjimg River, and the water can now by gravity to the most parts of Huang-Huai-Hai plain. Passing the east of the third terrace, ERP will pump water north due to its lower diversion location.
I . Western Route Project (WRP)
As the strategic project to solve the problem of poorer water resources in Northwest and North China, WRP will divert water from the upper reach of Changjimg River into Huanghe River.
Since 1952 when an investigation team was organized by Yellow River Conservancy Commission (YRCC), the relative units have done a great number of investigation and plan and research works for more than 40 years. In 1987, State planning Commission classified WRP as a project of pre-earlier-stage study, and asked to make a 10-year study to provide the possibi1ity and reasonableness of WRP. Since then, YRCC and other relative units have done a lot of basic works in transfer district and nearby located in remote and cold and oxygen-lackings area, and submitted Preliminary Report on Western Route Project for South-to-North Water Transfer and Findings Report on Yalongjiang Water Transfer Project to State Planning Commission and Ministry of Water Resources for examination. Up to now, the findings on Tongtianhe River and Daduhe River Water Transfer Projects have almost been completed. It was planned that Comprehensive Findings Report on Western Route Project for South-to-North Water Transfer would be submitted in1996.
Transferable water quantity and scope of water supply
In the 1950s and 1960s, it was considered to divert water from Tongtianhe, Yalongjiang, Daduhe, Lancangjiang, Nujiang Rivers. But these considerations could be the long-range plans due to the large projects 'engineering scale.
In the last decade, YRCC has focused on studying water transfers from Tongtianhe, Yalongjiang, Daduhe Rivers. In accordance with the initial study results, from those three rivers, the maximum transferable water quantity about 20 billion m3, including 10 billion m3 from Tongtianhe River, upper reach of Changjiang River, and about 5 billion m3 from Yalongjiang, a tributary of Changjiang River, and 5 billion m3 from Daduhe River. The water diverted will be supplied for Qinghai, Gansu, Shannxi, Shanxi Provinces, and the Ningxia Hui Autonomous Region and the Nei Mongol Autonomous Region.
Layout of WRP
Bayankala Mountain lies between Huanghe River and Changjiang River. The elevation of the bed of the Huanghe River is higher than that of the correspondent section of Changjiang by 80-450 m. It is necessary for the water transfer project that a high dam will be constructed for damming water or some pumping stations be set up for lifting water, and some long tunnels will be driven through Bayankala Mountain. Two methods of water diversion, flowing by gravity and by pumping were considered. But for each of them, a high dam in height of 200 m or so will have to be constructed and some long tunnels over 100 km in length to be driven.
Preliminary study on water diversion route is as follows.
(1) Yalongjimg Diversion Route:
A diversion route by gravity was selected. The Hydraulic Project will be constructed on Changxu Reach of Yalongjiang River, the water will be diverted from Changxu to Qiaqeinong Ditch, a tributary of Huanghe River. The height of the dam is 175 m, the diversion route is a tunnel, which is 131 km in total length.
(2) Tongtianhe Diversion Route:
This is a combining development scenario of the Yalongjiang and Tongtianhe diversion routes. The condition is that Yalongjiang diversion route must be the priority construction.
The Hydraulic Project will be constructed on Tongjia Reach of Tongtianhe, the water by gravity will be diverted from Tongtianhe Project to Yalongjimg River, then, to Qiaqeinong Ditch. The height of the dam is 302 m. The Diversion Route is in fact a tunnel, 289 km in total length, including 158 km from Tongjia Dam to Yalongjimg River and 131 km from Yalongjiang River to Qiaqeinong Ditch, a tributary of Huanghe.
(3) Daduhe Diversion Route:
A diversion route by pumping was elected. The Hydraulic Project will be constructed on Xierga Reach of Zumuzu River, a tributary of the upper reach of Daduhe, the height of the dam is 296 m. The water by pumping wi1lbe diverted from Xierga Hydraulic Project to Jiaqu River, a tributary of Huanghe, total length of the diversion route is 3O km, including a 28.5 km tunnel. The lifting height of the pumping station is 458 m, the mean annual power consumption is 7.1 billion kwh.
Benefits of project
20 billion m3 water from three rivers will be diverted by WRP to increase the irrigated area by 30 million mu and to supply living and industrial water by 9 billion m3 for Qinghai and Gansu and Shanxi and Shanxi Provinces, and Ningxia Hui and Nei Mongol Autonomous Regions, consequently promoting the economic development of Northwest and inland areas, and improving the biological environment of Northwest Loess Plateau.
Technical feasibility
WRP will be located in Qinghai-Tibet Plateau, with an elevation of 3000-5000 m. For WRP, a high dam with the height of 200 m or so will be constructed, and some long tunnels over 100 km with the burden of hundreds meters will be driven in this very cold area which is also the one of areas with the most complex geological structure. The earthquake intensity of most parts of this area is over 6-7 degrees with the max intensity of 8-9 degrees on the modified-Mercalli scale. The construction of WRP with complex technology will must be faced with many difficulties of environment. Therefore, it is required to strengthen earlier-stage studies and scientific research to solve the above problems.
II. Middle Route Project (MRP)
The middle Route Project (MRP) for South-to-North Water Transfer will divert water, in the near future, from Danjiangkou Reservoir on the Haijiang, a tributary of Changjiang River, to Beijing City through Canals to be built along Funiu and Taihang Mountains. In the far future, additional water is due to be obtained from Three Gorges Reservoir or the downstream of the dam on main Changjiang. The advantages of this project lie mainly in good quality of the water to be diverted, greater water-supply coverage available, that water can be conveyed by gravity. The project will be an important and basic facility for mitigating the existing crisis of water resources in North China.
It has been already 40 years since the earlier stage study on the MRP started in the early 1950s. In these years, Changjiang Water Resources Commission, and other relative provinces, cities, and departments have performed a lot of investigation, plan, design and research works.
In January 1994, Ministry of Water Resources examined and adopted "Feasibility Study Report on MRP for South-to-North Water Transfer" made out by Changjiang Water Resources Commission, and gave a proposal to build this project to State Planning Commission.
Transferable water quantity and scope of water supply
Based on the completion of Danjiangkou Reservoir extending, mean annual water quantity to be diverted will be 14.14 billion m3, and 11 billion m3 for the dry year (75% guarantee rate). The normal water level of Danjiangkou Reservoir will be at 170.0 m. In accordance with the development level in 2020, some compensative projects will be built on the middle and lower Hanjiang to ensure the development of industry and agriculture, and the navigation and the environment of the water exporting region.
MRP will supply water for Tang bai he Plain, middle and western parts of Huang-Huai-Hai Plain, with a total area of about 155,000 km2. Since the limitation of water quantity in Hanjiang River, MRP cannot meet all the requirements of planned water supply areas, only provide water for municipal and industrial use in Beijing, Tianjin Municipalities, and Hebei, Henan, Hubei Provinces, and give consideration to the agriculture and other use of water in some partial areas.
Layout of MRP
The main works of MRP will be composed of two major parts: the engineering structures in water source region and the water conveyance systems. The former includes Danjiangkou Dam Extension Project on the Hanjiang and compensative projects for its middle and lower reaches, and latter includes the main trunk canal for diverting Hanjiang and Tianjin main canal.
1.Engineertng structures in water source region
(1) Danjiangkou Dam Extension Project
Controlling 60% of the total drainage area of Hanjiang River basin, Danjiangkou Reservoir has a mean annual natural runoff of 40.85 billion m3. Taking account of the development of upper reach, the reservoir was expected to receive a mean annual inflow of 38.54 billion m3.
Based on the engineering scale already in place, it is planned to continue to complete Danjiangkou Project to its final scale, namely, to heighten the dam from its existing crest elevation of 162 m up to176.6 m, with the design storage level raised from 157 m to 170 m and the total storage capacity consequently increased to 29.05 bi1lion m3. This means to gain, as against the initial figures, an additional reservoir storage capacity of 11.6 billion m3, an increased available regulation storage capacity of 8.8 billion m3 and an extra flood control storage capacity of 3.3 billion m3.
The normal storage water level of Danjiangkou Reservoir will be at 170 m in its final configuration, with the additional inundated area of 370 km2. In accordance with the investigation in 1992, the main inundation indices are as follows:
· population: 224 thousand people.
· houses: 4.794 million m2.
· cultivated land: 0.235 million mu.
· industrial and mining enterprises: 120 (including the rural and township ones)
· fixed assets inundated in original value: 120 million yuan.
(2) Compensative projects for middle and lower Hanjiang
To transfer water of more than 14 billion m3 in near future and avoid the available harmful effects on water use for industry, agriculture and navigation in the middle and 1ower Hanjiang Basin, it is required to newly construct Xinglong or NianpanShan Hydraulic Project on Hanjiang as part of the proposed main river canalization project and a water compensating project diverting water from Changjiang to Dongjianghe, and to modify or extend part of the existing sluices and pumping stations, and to build some additional navigation regulating works as well.
2.Water conveyance systems
(1) Main trunk canal
Since the limitation of the location of the existing canal head, Fangcheng Saddle on the watershed between Changjiang and Huaihe Rivers, the range of passing Huanghe, the line of main trunk canal of MRP in the south of Hulanghe is clear. As to the main trunk canal in the north of Huanghe, two alternatives have been compared, utilizing the existing river channels or excavating new canals. In accordance with ensuring water quality and realizing of flowing by gravity in the whole route, the later, excavating new canals, was selected.
The main trunk canal, started at Taocha canal head, passing the 8 km existing channel, northeast along the south side of Funiu Mountain, going through NanYang City and crossing Bait1e River, will enter Huaihe Basin by passing FangCheng saddle on the watershed. Then, through Baofeng County, Yuzhou County, and the west of Xinzheng, the main trunk canal will cross Huanghe at Gubaizui in the northwest of Zhengzhou City, the capital of Henan Province, and extend on the North China Plain between the eastern Taihang Mountain and the western Beijing-Guangzhou Railway, and enter hilly area in Tangxian, and enter Beijing Metropolis by crossing the northern Juma River, and enter Beijing urban district by crossing Yongding River, and terminate at Yuyuan Pool. The total length of the trunk canal is 1241.2 km.
Tianjin main canal is 142 km in total length, from the diversion spot on the main trunk canal in the north of Xiheishan in Xushui County, Hebei Province, to Xihe Sluice of Tianjin.
The design water level at the head of main trunk canal is 147.2 m, and that at termination is 49.5 m. The water diverted can now by gravity along the whole main trunk canal. The water levels and flows at main control points are as follows:
The longitudinal gradient of the canal is 1/25000 for the sections in the south of Huanghe and 1/30000-1/15000 for those in the north of Huanghe. For the purpose of seepage control and roughness-reducing, the whole canal will be full section lined all along the route with concrete, cement-treated soil, shotcrete facing and the like in accordance with the foundation conditions.
The design now for the canal is progressively reduced from the south to the north, with water depth decreased from 9.5 m to 3.5 m, and bottom width changed in the range of 56-7 m.
The engineering geologic conditions and major geologic problems along the main trunk canal have been mainly made clear. As for some local engineering geologic troubles relative to bentonite and loess, such as canal slope stability, shock-induced liquefaction failure of sandy soils, earthquake resistance in high earthquake intensity region, subsiding of underlying coal and mined hollow zones, they all can be readily solved and treated by adopting corresponding measures.
Linking up four major river valleys, Changjiang, Huaihe, Huanghe and Haihe, the main trunk canal will have to run across 219 rivers, medium or small, each covering a drainage area of over 10 km2, inclusive of the main Huanghe, and 44 railways. It is thus required to build, on the main trunk canal, various structures, large-or small-size, totalling936, such as regulating, diversion and tailrace structures as well as tunnels and closed conduits, including 571 canal-crossing highway bridges, the largest in scale of which is Huanghe-crossing Project. On Tianjin main canal across 48 rivers, there will be a total of 119 such hci11ties.
(2) Huanghe-crossing Project
The main trunk canal will cross Huanghe in Taohuayu Reservoir under the comprehensive planning of Huanghe Basin. Since its complex problems and large scale and investment, the Huanghe-crossing project will be the most critical structure on the trunk canal. Based on the comprehensive Study and comparison among the many alternatives, the aqueduct and the tunnel siphon are technically feasible. Since the tunnelling method can avoid the contradiction to the water conditions and the plan of Huanghe, and the tunnelling method with shield have been a successful experience in domestic and overseas, it was recommended that the alternative of tunnelling at Gubaizui would be adopted in accordance with the canals on both banks.
The tunnels crossing Huanghe will be 7.2 km in total length. For it, the design water diversion now is 500 m3/s. The project includes two tunnels with the internal diameter of 8.5 m.
3. Main engineering quantities and investment
· Earth excavation: 0.6 billion m3
· Rock excavation: 0.06 billion m3
· Earth/rock fill: 0.23 billion m3
· Concrete: 15.83 billion m3
· Cement-modified soil for lining: 7.18 billion m3
· Steel: 0.7 billion m3
· Permanent requisition land: 0.422 billion mu including inundated area of 0.235 billion mu
· Temporari1y occupied area: 0.11 billion mu
There are two key factors controlling the construction schedule of MRP. They are Danjiangkou Reservoir resettlement and Huanghe-crossing Project on the main trunk canal. In accordance with driving tunnel by slurry shield machines, the Huanghe-crossing project will require a construction period lasting about six years and some preparatory time.
In accordance with the price level by the end of 1993, the total static investment for MRP equals to about 40 billion yuan.
Benefits of project
MRP will mitigate the crisis of water resources in Beijing Tianjin and North China, and increase irrigated area by 9 million mu, 6.4 billion m3 for municipal and industrial water supply, 3.0 billion m3 for agriculture, for Beijing, Tianjin, Hebei and Henan, and significantly improve the biological environment and investment environment of receiving areas, and boost the economic development in Middle China.
Heightening Danjiangkou Dam will increase the ability for flood control of middle and lower Hanjiang and assure the safety of Wuhan City and the plain in the north of Hanjiang.
III. Eastern Route Project (ERP)
This project will divert water from the lower reach of Changjiang north to supply water for the eastern Huang-Huai-Hai Plain with the termination in Tianjin City by raising water in stages through Beijing-Hangzhou Grand Canal.
ERP was initially considered in the early 1950s. Since the heavy drought of North China in 1972, under the leadership of then Ministry of Water Resources and Electric Power, Planning Office of South-to-North Water Transfer has organized Huaihe Water Resources Commission, Haihe Water Resources Commission, Tianjin Hydroelectric Investigation and Design Institute, relative provinces and cities and agencies, to do a great number of investigation, design and research works for more than 20 years. In 1976, the Planning Report on Project in Near Future for South-to-North Water Transfer was submitted to the State Council for preliminary examination. In March 1983, the State Council approved the Feasibility Study Report on First-stage Engineering of ERP for South-to-North Water Transfer issued by Ministry of Water Resources and Electric Power. In September 1993, Ministry of Water Resources, jointly with some provinces and cities concerned, examined and adopted the Revised punning Report on ERP for South-to-North Water Transfer and Revised Feasibi11ty Study Report on First -stage Engineering of ERP for South-to-North Water Transfer.
Scale of ERP and water quantity to be diverted
There is the richer water in the lower reach of Changjiang River, with mean annual water of 956 million m3 entering sea, and more than 600 billion m3 even in extreme dry year. Therefore, ERP will have enough water to be pumped north, and the water quantity to be diverted is based on the scale of ERP.
The rational final engineering scale of ERP was considered in planning. The development level in 2020 was taken as the objective planning scale and the successfully diverting water into North China as the first-stage objective. The water quantities to be diverted in various stages are listed in the following table:
ERP will supply water for Jiangsu, Anhui, Shandong, Hebei Provinces and Tianjin Municipality. In details, the receiving areas will include, the plain on the lower Huaihe except the hinterland and its east of Lixiahe Region and the northern plateaus in Northern Jiangsu, the areas on both banks of lower Huaihe River from Bengbu City and on both banks of Xinbian River in the east of Huaibei City and parts of Tianchang County in Anhui Province; the areas along Nansi Lakes and Hanzhuang Canal and Liangji Canal, parts of eastern Jiaodong Peninsula, and northern area which cannot be irrigated by the water of Huanghe in Shandong Province; Heilonggangang and Yundong regions in Hebei Province; Tianjin City and its suburbs.
Layout of ERP
ERP will be built on the basis of the existing water diversion project from Changjiang in Jiangsu Province, Beijing-Hangzhou Grand Canal, Huaihe harnessing projects and the other relative projects. ERP will consist of water conveyance system, impounding project, power supply system.
1.Water conveyance system
Water conveyance system will include the main diversion channel, pumping station, Huanghe-crossing project and the relative treatment projects.
(1) Diversion channel
There will be two diversion spots, Sanjiangying where Huaihe River enters Changjimg and Liuwei where Beijing-Hangzhou Grand Canal crosses Changjiang. The diversion channel will be 1150 km in total length from Changjiang to Tianjin trunk route, including 651 km section in the south of Huanghe, 9 km Huanghe-crossing section, 490 km section in the north of Huanghe. There will be 740 km in a total length of subsidiary routes including 665 km in the south of Huanghe. 90% of the diversion channel will be made for use of the existing river channels.
Beijing-Hangzhou Grand Canal will be the trunk diversion channel. Some subsidiary diversion routes will be added to partial diversion channel sections.
(2) Pumping station
The topography along Huanghe River is of the higher center. The diversion spot will be lower than the surface near Huanghe by more than 40 m. It is needed to construct 13 pumping stations to pump water from Changjiang to southern bank of Huanghe with the total lifting height of 65 m. The water crossing Huanghe can now by gravity to Tianjin. In the south of Huanghe, there will be a stage for Nansi Lakes section, and three stages for each of other sections. There will be 30 pumping stations including 13 on the trunk and 17 on the subsidiary ones, with the total design pumping capacity of 10200 m3/s and the total installed capacity of 1017.7 MW. Seven existing pumping stations with the design pumping capacity of 1100 m3/s and the installed capacity of 110.5 MW wi11 be modified for the use of ERP.
In the first-stage engineering of 13 stages, 23 pumping stations with the installed capacity of 453.7 MW will be built.
In the north of Huanghe there will be 5 pumping stations for impounding pools with the design pumping capacity of 326 m3/s and the installed capacity of 14.6 MW.
The characteristics of the pumping station of ERP will include low lifting height (2-6 m), large now (15-40m3/s for each unit), long operating time (5000 hours/year for the stations in the south of Huanghe). Some pumping stations responsible for waterlogging drainage wil1 have to be of operating mobility and high efficiency.
(3) Huanghe-crossing project
The alternative of tunnelling under Huanghe between Dongping County and Dong'e County of Shandong Province was selected. On the basis of long-term geological investigation and the Huanghe-crossing exploratory tunnel excavation, the relative units have found out the foundation structure and the karst development in the riverbed under Huanghe, and solved successfully the problem of leekage control for excavation under the riverbed.
Huanghe-crossing section is 8.67 km in total length from the outlet of Dongping Lake to the inlet of Weilin Canal, including siphon section of 634 m. The two horizontal tunnels with the diameter of 9.3 m will be located 70 m under the riverbed of Huanghe. For the first stage engineering, one of the two tunnels will be driven.
2.Impounding projects
The impounding projects are the necessary measures of long-distance water transfer. Along ERP in the south of Huanghe, there are some lakes such as Hongze Lake, Luoma Lake, Nansi Lakes, Dongping Lake, that can be as the impounding projects for ERP with the total regulating storage capacity of 7.57 billion m3 by repairing slightly. No new impounding project will be needed. In the north of Huanghe, Beidagang Reservoir in Tianjin City can be continuously used, and Tuanbowa in Tianjin City and Qianqingwa in Hebei Province will be extended for use, and Dalangdian and Langwa in Hebei Province will be newly built. So there will be 5 impounding projects with the total storage capacity of 1.49 billion m3 in the north of Huanghe.
3.Power supply system
There will be 30 pumping stations with the new installed capacity of 887.7 MW and the mean annual power consumption of 3.82 billion kWh and the annual maximum 5.75 billion kWh. For the first stage engineering, there will be 23 pumping stations with the new installed capacity of 343.2 MW and the mean annual power consumption of 1.9 billion kWh.
4.Main engineering quantities and investment
· Earth/rock volume (106 m3): 776/304
· Engineering in the south of Huanghe (106 m3): 533/176
· Concrete (106 m3): 5.29/1.43
· Installed capacity to be increased for pumping stations (MW): 921.8/344.1
· Power commission line's to be erected (km): 1326/1282
· Permanent and temporarily occupied land (mu): 339100/302100
· Relocation of houses (room): 76000/76000
In accordance with the price level in 1993, the total investment for ERP equals to about 20 billion yuan. For the first stage engineering, some 9.4 billion yuan will be required.
Benefits of Project
ERP will increase supply Jiangsu, Anhui, Shandong, Hebei and Tianjin with 14.33 billion m3 water, including 6.656 billion m3 of living, industry and navigation, and 7.676 billion m3 of agriculture.
The ERP completed will basically solve the problems in shortage of water resources in Tianjin Municipality, Heilonggang and Yundong regions in Hebei Province, north and southwest and part of Jiaodong Peninsula of Shandong Province, and make the supplying water for Beijing available, consequently prompting economic development of Bohai Sea area and eastern Hulang-Huai-Hai Plain, and improving the environment deteriorated from the shortage of water.
ERP will ensure the annual navigation from Jining to xuzhou on Beijing-Hangzhou Grand Canal, and make two commodity grain bases in Western Shandong and Northern Jiangsu strong and developed.
Conclusion
The South-to-North Water Transfers is an important strategic measure in the optimization of water resources distribution of China. As the specific geographic location and the limited water quantity of the water providing area, each of the West Route, the Middle Route and East Route has its own rational scope of irreplaceable water supply area, according to the requirement of relative regional economic development, the preparation of pre-construction and the ability of the state finance and other conditions. The South-to-North Water Transfers Project will be carried out in steps.
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