Optimal Operation for Baoying Pumping Station in East Route Project of South-to-North Water Transfer

Baoying pumping station is a part of source pumping stations in East Route Project of South-to-North Water Transfer in China. Aiming at the characteristics of head varying, and making use of the function of pump adjustable blade, mathematical models of pumping station optimal operation are established and solved with genetic algorithm. For different total pumping discharge and total pumping volume of water per day, in order to minimize pumping station operation cost, the number and operation duties of running pump units are respectively determined at different periods of time in a day. The results indicate that the saving of electrical cost is significantly effected by the schemes of adjusting blade angles and time-varying electrical price when pumping certain water volume of water per day, and compared with conventional operation schemes （namely, the schemes of pumping station operation at design blade angles based on certain pumping discharge）, the electrical cost is saved by 4.73%-31.27%. Also, compared with the electrical cost of conventional operation schemes, the electrical cost is saved by 2.03%-5.79% by the schemes of adjusting blade angles when pumping certain discharge.

Research on Expansive Soils Encountered in Middle Route Project of South-to-north Water Transfer Canal

The main canal of the Middle Route Project of South-to-North Water Transfer totals more than 1 240 km in length. In Henan Province and Hebei Province, there will be a section of more than 120 km passing through an expansive soils area. Expansive soils is a special kind of tenacious clay, which swells when meeting with water and shrinks when losing water. With complicated mechanical properties, it changes with the variation of water content. As a result, expansive soils become the key object of study on unsaturated soils mechanics for the project. From the status of study on unsaturated soils at home and abroad, this paper covers an analysis on stability analysis method of expansive soils slope, determination of expansive soils strength, rational design of canal slope ratio and support, and forecast of landslide for the Middle Route Project of South-to-North Water Transfer.

Geological conditions and key rock mechanics issues in the Western Route of South-to-North Water Transfer Project

In terms of special geological conditions of the Western Route of South-to-North Water Transfer Project, the classification method for surrounding rocks is discussed by combining with the construction method of tunnel boring machine （TBM）. The classification standard of surrounding rocks is put forward on the basis of physical simulations and engineering practices. Damage, deformation and evolution of surrounding rocks induced by TBM excavation are discussed. Meanwhile, the long-term deformation mechanisms and stability of surrounding rocks are also studied. On this basis, a three-dimensional constitutive model for interbedded sandstone slate and a fiat shell-joint element-foundation system for calculating internal forces of segment lining are established. The deformation features of surrounding rocks of deep and steep interbedded sandstone slate and their influences on internal forces of segment lining are presented. Finally, the design methods of segment lining constructed in deep and steep flysch are proposed.

Forecasting Loss of Ecosystem Service Value Using a BP Network: A Case Study of the Impact of the South-to-north Water Transfer Project on the Ecological Environmental in Xiangfan, Hubei Province, China

Objective To recognize and assess the impact of the South-to-north Water Transfer Project (SNWTP) on the ecological environment of Xiangfan, Hubei Province, situated in the water-out area, and develop sound scientific countermeasures. Methods A three-layer BP network was built to simulate topology and process of the eco-economy system of Xiangfan. Historical data of ecological environmental factors and socio-economic factors as inputs, and corresponding historical data of ecosystem service value (ESV) and GDP as target outputs, were presented to train and test the network. When predicted input data after 2001 were presented to trained network as generalization sets, ESVs and GDPs of 2002, 2003, 2004... till 2050 were simulated as output in succession. Results Up to 2050, the area would have suffered an accumulative total ESV loss of RMB 104.9 billion, which accounted for 37.36% of the present ESV. The coinstantaneous GDP would change asynchronously with ESV, it would go through an up-to-down process and finally lose RMB89.3 billion, which accounted for 18.71% of 2001. Conclusions The simulation indicates that ESV loss means damage to the capability of socio-economic sustainable development, and suggests that artificial neural networks (ANNs) provide a feasible and effective method and have an important potential in ESV modeling.

Price Analysis of Water Supply for South-to-North Water Transfer Project

The factors influencing the water supply price of a hydraulic project include natural conditions and economic policies. This paper thoroughly demonstrates the water price of South-to-North Water Transfer Project from the viewpoint of economic policies. It is considered that if the project is assigned as a profitable one and built depending on commercial loan from bank completely or mostly, the water price will be too high to be undertaken by users,and if the project places the public good at first while considering the economic benefit, its investment mainly relies on the state (national or local governments) appropriation and self-raised funds and a little from the bank loan on favorable terms, the price determined according to the principle of satisfying the cost and reasonable profit will be relatively lower and can be undertaken by the users in the North China where water shortage is serious. The problem of higher water price of agricultural irrigation to the north of the Yellow River can be tackled by taking measures such as "compensating agriculture by industry" according to foreign practical experiences and relevant suggestions.

Asynchronism-synchronism of regional precipitation in South-to-North Water Transfer planned areas

This paper proposes a method on analyzing the asynchronism-synchronism of precipitation of different hydrological regions regarding the S-to-N water transfer areas of eastern China. The general process of the analysis includes three steps. Firstly, we created the rainfall series of the region concerned by calculating the regional average rainfall of the stations in the area with the help of the classical Thiessen Polygon method. Secondly, the standards of assessment indices for wetness or dryness are set according to Gamma distribution function with a certain probability P 37.5% or 62.5% given respectively. Finally, the frequency of nine combinations are counted as the quantitative feature of asynchronism and synchronism in three time scales, that is the yearly, seasonal and monthly scales. The asynchronism-synchronism of two region pairs has been estimated. The results show that the frequency of precipitation asynchronism in 1957–1998 is larger than the synchronism frequency for both the North China-middle and lower Yangtze River pair and for the North China-upper Hanjiang River pair. As for the synchronism phenomena, the frequency of Nd?Sd is rather low. As the combinations that are suitable for water transfers are Nd?Sw, Nn?Sw, Nd?Sn and Nn?Sn, the total frequency of these combinations for North China-middle and lower Yangtze River is 40% on an annual basis, but only 28% in spring when water shortages are most likely to occur. The total frequency of these combinations for North China-upper Hanjiang River is about 24% on an annual basis, but 35% in spring and winter. It should be noted that if future precipitation patterns are similar to that of the period 1957–1998, it is very important to change the natural character of asynchronism-synchronism by enhancing the capability of hydro-projects regulation and improving management of the water transfer project.

Quantitative standard of eco-compensation for the water source area in the middle route of the South-to-North Water Transfer Project in China

The Middle Route Project(MRP)of the Southto-North Water Transfer Scheme(SNWT)in China will require a very large financial expenditure to ensure the water supply and the associated water quality to northern China.An eco-compensation mechanism between the water service source areas and its beneficiaries is essential.This paper establishes an analytic framework of ecocompensation standard for the protection of the water source area,including both the calculation of ecocompensation based on opportunity cost method(OCM)and calculation of the burden sharing of eco-compensation between the water source area and the external water reception area based on the deviation square method(DSM).Taking Shiyan City,Hubei Province in China as a case study,our results show that the eco-compensation in the first-phase of MRP for the water source area in Shiyan,Hubei Province should be 1.63×10^(10) CNY,about four times of planned eco-construction investment budget(4.33×10^(9) CNY).In addition,the burden sharing of eco-compensation varied greatly in terms of different methods.It would be better to integrate the results of different single-factor burden sharing methods by determining the corresponding weighting coefficient with DSM and form one unanimous consent result by the interested parties.

Simulation of Transport Channel in China's Middle Route South-to-North Water Transfer Project

The unsteady flow in the Middle Route South-to-North Water Transfer Channel was simulated numerically using an implicit solution procedure for the Saint Venant equations. An equivalent roughness was used to simulate the effect of many transfer structures on the water levels in the main channel. Various gate operating and control methods were analyzed to study the response to disturbances produced by varying the flow rates through the Tianjin outlet. The results show that when the inflow at the head changes in the same way as the sum of the flow rates through all the outlets, the transition time and the fluctuation of the water levels using the timed gate operation method are less than when using the simultaneous gate operation method, but the variations of the gate openings and flow rates through each control gate are much larger. The flow disturbances produced by the Tianjin outlet can be rectified within several channel sections and the transition time can be greatly shortened by allowing the water levels immediately upstream of the control gates to vary within proscribed ranges, rather than being held constant.

Water transfer determines the regional spread dynamics of non-native fish species

Interbasin water transfer projects(IBWT's)have emerged as dispersal corridors for aquatic species.However,little is known about how water transfer affects regional spread dynamics,or shapes the genetic diversity patterns of non-native populations.Shimofuri Goby Tridentiger bifasciatus is a globally introduced fish species with many wellestablished populations in IBWT's.Here,we used nuclear microsatellites to assess the genetic diversity and population structure of the Shimofuri Goby in its native and introduced sites belonging to two IBWT's in China.Our objectives were to(1)reveal the genetic diversity patterns of the Shimofuri Goby during regional spread,and(2)identify its mode of spreading in water transfer systems.We observed(1)a high level of genetic diversity in non-native populations without evidence of bottleneck effects,(2)that non-native populations with a longer water transfer times had a higher private allele richness,and(3)that non-native populations showed a highly mixed genetic structure,low level of genetic differentiation,and no significant relationship between geographical and genetic distances.Our results indicate that the genetic patterns of diversity of non-native populations are mainly shaped by a linear cascade spread processes due to long-distance movement of larvae,and are probably related to propagule pressure caused by the construction of water transfer.To manage the non-native populations of T.bifasciatus,preventive actions and physical removal should be implemented in IBWT's.

Ecological assessment of lakeshore wetland rehabilitation on eastern route of South-to-North Water Transfer Project

To evaluate the ecological effects of lakeshore wetland rehabilitation on the eastern route of the Southto-NorthWater Transfer Project,species composition,coverage,height,and biomass of wetland communities at 22 sites of the study area on the shore of Nansi Lake in April and May 2007 were investigated.The wetlands under investigation were divided into platform fields,transition zones,and shallow water zones according to differences in elevations,water levels,and human activities.The species richness index,Shannon-Wiener index,Simpson index,and Pielou Evenness index were adopted to delineate and discuss the ecological effects of lakeshore wetland rehabilitation in 22 quadrates.Results showed that the species richness of the wetland areas after 2 years’rehabilitation amounted to 47 of 24 families,higher than 25 of 20 families in areas without rehabilitation.The biodiversity index and abundance index of rehabilitated areas were also higher than those of platform fields and fish ponds where there was no rehabilitation.In addition,the Shannon-Wiener index,Simpson index,and community evenness index of platform fields in rehabilitated wetland areas were 1.619,0.745,and 0.860,respectively,higher than those of the platform fields before rehabilitating.The results suggested that the constructed lakeshore wetland played an important role in protecting the diversity of species.

2-D NUMERICAL SIMULATION OF FLOODING EFFECTS CAUSED BY SOUTH-TO-NORTH WATER TRANSFER PROJECT

Since the General Channel designed for the South-to-North Water Transfer Project in China has to cross many rivers and streams flowing from west to east, there are potentially serious effects additional flooding on the western side of the project alignment. Therefore, a 2-D numerical model for forecasting basin flood disasters was established and verified using historical flood data. The model was applied to researching the interaction between the proposed Project and flooding events for 5 streams in the Anyang River reach as a representative case study. Simulated results indicate that the model could correctly forecast the flood, submerged area and depths, and water surface elevations along the left side of the channel. The discharge capacity and location of hydraulic structures in the transfer canal alignment were analyzed. Then adjustments to the dimensions and positioning of proposed hydraulic structures were recommended at intersections, especially the addition of a channel to transfer flood water from one stream to another, which can effectively limit the sluice and protect the Anyang City from flooding.

预应力矩形渡槽温度应力有限元分析

结合南水北调泲河渡槽工程实例。通过运用三维有限单元法对预应力混凝土矩形渡槽的受力性能进行数值模拟。重点分析预应力和温度荷载对渡槽应力的影响。热应力耦合采用顺序耦合法来实现。计算结果表明:渡槽内力及预应力配筋分布合理,混凝土应力满足规范要求,温度荷载对槽身应力有较大影响。

竖井投料对大伙房水库输水隧洞混凝土性能影响分析

"辽宁省大伙房水库输水(一期)工程"为长距离隧洞引输水工程,隧洞衬砌混凝土施工中应用了竖井投料方法,竖井深度从60～120m不等。通过还原试验,研究竖井投料对混凝土拌和物中粗细骨料级配及硬化后混凝土强度及耐久性指标的影响程度。通过对试验检测数据分析可知,一定深度范围内,采用适合的竖井结构,竖井投料对混凝土拌和物中粗细骨料及硬化后混凝土强度及耐久性指标影响不大。

白洋淀生态补水分析与研究

白洋淀作为华北最大的淡水湖,最近几十年连续出现干淀现象及大量污水进入白洋淀,白洋淀生态环境遭到严重破坏。分析了利用南水北调初期富余水量向白洋淀进行生态补水的可能性,并进行了输水线路的方案比选,提出了由南水北调中线总干渠蒲阳河退水闸向白洋淀输水的最优线路。

Estimating the minimum in-stream flow requirements via wetted perimeter method based on curvature and slope techniques

Under the assumptions of triangular cross section channel and uniform stable flow, an analytical solution of the minimum ecological in-stream flow requirement （MEIFR） is deduced. Based on the analytical solution, the uncertainty of the wetted perimeter method is analyzed by comparing the two techniques for the determination of the critical point on the relationship curve between wetted perimeter, P and discharge, Q. It is clearly shown that the results of MEIFR based on curvature technique （corresponding to the maximum curvature） and slope technique （slope being 1） are significantly different. On the P-Q curve, the slope of the critical point with the maximum curvature is 0.39 and the MEIFR varied prominently with the change of the slope threshold. This indicates that if a certain value of the slope threshold is not available for slope technique, curvature technique may be a better choice. By applying the analytical solution of MEIFR in the losing rivers of the Western Route South-to-North Water Transfer Project in China, the MEIFR value via curvature technique is 2.5%-23.7% of the multi-year average annual discharge, while that for slope technique is 11%-105.7%. General conclusions would rely on the more detailed research for all kinds of cross-sections.

Coupling interaction between biodiversity and aquatic habitat area in Western Route Project vicinity

The Western Route of the South-to-North Water Transfer Project will divert water from the upper Yangtze River and its tributaries, the Dadu River and Yalong River, to the upper Yellow River. The project may ease the water shortage in the Yellow River Basin. However, it may also have some effects on the ecosystem in the upper Yangtze River Basin. Benthic invertebrates play an important role in the river ecosystem, particularly in the circulation of materials and nutrition. Benthic invertebrates are widely used to quickly assess river ecosystems because of their rapid response to changes in the water environment. The diversity of benthic invertebrates is closely associated with the aquatic habitat area. This study examined this interaction by sampling the benthic invertebrates in an expanding area. The conclusions are that the diversity of benthic invertebrates begins to decrease when the aquatic habitat area is reduced to 45% of the original area, and decreases dramatically when the aquatic habitat area is reduced to 10% of the original area. The aquatic habitat area should be kept at more than 45% of the original area in order to maintain the significant diversity of benthic invertebrates.

Inferring decelerated land subsidence and groundwater storage dynamics in Tianjin–Langfang using Sentinel-1 InSAR

To meet the growing demand for socioeconomic development,a large amount of groundwater is extracted from confined aquifers worldwide.The North China Plain has experienced considerable groundwater depletion and subsidence during the past six decades.In this study,we use Sentinel-1A/B SAR images from 2015 to 2020 to map the ground subsidence of the Tianjin–Langfang area.Three subsiding zones centered at Guangyang,Wuqing–Bazhou,and Jinghai are identified with maximum subsidence rates of 98.1,121.8,and 104.7 mm/yr.Seasonal and long-term signals are separated from time series subsidence and hydraulic measurements using continuous wavelet transform to retrieve aquifer parameters.The long-term subsidence,which fits well with an exponential decaying model,remarkably slows down in our study area.The elastic skeletal storage coefficients range between 0.52×10−3 and 9.66×10−3.We then retrieve the spatial–temporal variations of total groundwater storage,recoverable groundwater storage,and irreversible groundwater storage.Groundwater storage depletion rates are apparently reducing,which benefits from the operation of the South-to-North Water Transfer Project and local groundwater management practices.

Drought analysis using multi-scale standardized precipitation index in the Han River Basin,China

Regional drought analysis provides useful information for sustainable water resources management.In this paper,a standardized precipitation index(SPI) at multiple time scales was used to investigate the spatial patterns and trends of drought in the Han River Basin,one of the largest tributaries of Yangtze River,China.It was found that,in terms of drought severity,the upper basin of the Han River is the least,while the growing trend is the most conspicuous;a less conspicuous growing trend can be observed in the middle basin;and there is an insignificant decreasing trend in the lower basin.Meanwhile,the impact of drought on the Middle Route of the South-to-North Water Transfer Project was investigated,and it is suggested that water intake must be reduced in times of drought,particularly when successive or simultaneous droughts in the upper and middle basins of the Han River Basin occur.The results can provide substantial information for future water allocation schemes of the South-to-North Water Transfer Project.