Water-receiving Areas Research Articles

The unintended effects of inter-basin water transfer policies on corporate research and development activities

Abstract Inter-basin water transfer (IBWT) policies alter the spatial distribution of water endowments and trigger changes in environmental regulation policies, which may unintentionally impact the research and development (R&D) activities in IBWT water-receiving areas. However, the existing studies failed to examine the relationship between IBWT policies and corporate R&D activities, and lacked the exploration of the micro-mechanism of IBWT's unintended impact on corporate R&D activities. Through the water delivery of China's South-North Water Transfer Project as a quasi-natural experiment, this study adopts a difference-in-differences approach to scrutinise the unintended impact of IBWT policies on corporate R&D activities. The findings show that IBWT policies can make the water a ‘resource blessing’ by directly improving the water endowment in water-receiving areas, thereby promoting corporate R&D activities. In addition, IBWT policies can also indirectly encourage local governments in water-receiving areas to strengthen the intensity of environmental regulations, ultimately promoting companies to improve R&D activities. Finally, the impacts of IBWT policies on corporate R&D activities in water-receiving areas are heterogeneous. Overall, this study contributes to understanding the complicated relationship between IBWT policies and corporate R&D activities, and provides insights into how IBWT policies affect corporate R&D activities.

Integrated modeling framework to evaluate the impacts of multi-source water replenishment on lacustrine phytoplankton communities

An extensive artificial water diversion project aimed at alleviating the shortage of ecological water in lakes can change the original hydrological and physicochemical states and further affect the structure and distribution of phytoplankton communities. Therefore, it is important to fully evaluate the ecological restoration effect of the water diversion project on the water-receiving area before implementing water replenishment. For this purpose, we developed an integrated model framework based on the Environmental Fluid Dynamics Code (EFDC) and Random Forest (RF). We adopted a probability distribution method to address the uncertainty during model coupling. This framework was implemented to simulate and predict the evolution of phytoplankton diversity in Baiyangdian Lake (BL) in China. To solve the problem that the phytoplankton biodiversity in BL decreased especially in summer due to human activity, the Yellow River into BL, the south-to-north water diversion project, and joint replenishment of upstream reservoirs have been implemented in recent years. Our framework was used to analyze the biodiversity restoration effects of multi-source water replenishment through different routings. The results show that spatiotemporal coverage should be considered to reduce uncertainty during model coupling. Water replenishment has a positive impact on the biodiversity of BL; however, there are effective areas for phytoplankton diversity restoration, which are related to water quality and quantity, water replenishment routing and internal hydrological connectivity. The Xiaobai River has the most significant water ecological restoration potential among the routings, compared with that of the Baigou and Fu Rivers. Appropriate water replenishment in spring will play a vital role in alleviating the decrease in phytoplankton biodiversity in summer owing to flood control.

Slight flow volume rises increase nitrogen loading to nitrogen-rich river, while dramatic flow volume rises promote nitrogen consumption

Concentrated rainfall and water transfer projects result in slight and dramatic increases in flow volume over short periods of time, causing nitrogen recontamination in the water-receiving areas of nitrogen-rich rivers. This study coupled hydrodynamic and biochemical reaction models to construct a model for quantifying diffusive transport and transformation fluxes of nitrogen across the water-sediment interface and analysed possible changes in the relative abundance of microbial functional genes using high-throughput sequencing techniques. In this study, the processes of ammonium (NH4+–N) and nitrate (NO3−–N) nitrogen release and sedimentation with resuspended particles, as well as mineralisation, nitrification, and denitrification processes were investigated at the water-sediment interface in the Fu River during slight and dramatic increases in flow volume caused by concentrated rainfall and water diversion projects. Specifically, a slight flow volume rise increased the release of NH4+–N from the sediment, inhibited sedimentation of NO3−–N, decreased the mineralisation rate, increased the nitrification rate, and had little effect on the denitrification process, ultimately increasing the nitrogen load to the river water. A dramatic increase in flow volume simultaneously increased NH4+–N and NO3−–N exchange fluxes, inhibited the mineralisation process, promoted nitrification-denitrification processes, and increased inorganic nitrogen consumption in the river. This study provides a solution for the re-pollution of rivers that occurs during the implementation of reservoir management and water diversion projects. Furthermore, these results indicate a potential global nitrogen sink that may have been overlooked.

Online Public Opinion Mining for Large Cross-Regional Projects: Case Study of the South-to-North Water Diversion Project in China

Public perspective has long been ignored in ex-post evaluation of large cross-regional projects (LCPs), and the emergence of online public participation affords the opportunity to obtain and analyze public opinions from a wide range. Taking the South-to-North Water Diversion Project (SNWDP) as a typical LCP case, this study explored in depth the diverse and regionalized impacts of the project as reflected in online public opinion by developing an evaluation framework integrating post intensity, sentiment, and topic analyses. Leveraging lexicon-based sentiment analysis and latent Dirichlet allocation–based topic modeling technologies, patterns of public sentiments and topics were identified from spatial and temporal perspectives. The results showed that post intensity and public sentiment were significantly affected by project-related major events. A comparison of the water-donating and -receiving areas suggested that people in the water-receiving area had a more attentive and active attitude toward the project, and those in the water-donating area were predisposed to be more vigilant to negative events. Moreover, the variation of public sentiment across regions was found to largely depend on local social context. With regard to topic analysis, people in the water-donating and -receiving areas were more likely to focus on topics directly associated with their own interests, while the feasibility of the SNWDP garnered attention from both areas. In addition, project functions and significance as well as topical issues related to engineering corruption, water pollution, and security aroused widespread attention in all the areas under study. This study contributes to the literature on ex-post evaluation and public participation in the context of LCPs by incorporating online public opinion into the evaluation framework. The findings provide valuable insights for developing policies and strategies to improve the management of projects and to achieve an inclusive development process for projects of this type.

Monitoring Large-Scale Hydraulic Engineering Using Sentinel-1 InSAR: A Case Study of China's South-to-North Water Diversion Middle Route Project

The Middle Route of South-to-North Water Diversion (SNWD) Project,known as one of the greatest hydraulic projects of China, undertakes most of domestic and industrial water use in the Beijing&#x2013;Tianjin area, as well as a part of ecological water use. The whole canal should be monitored to ensure a continuous water supply for water-receiving areas. Compared with traditional ground-based monitoring tools limited by the low distribution density, intensive labor force, and huge cost, the satellite synthetic aperture radar interferometry (InSAR) with wide coverage, high-frequency revisiting, and low cost is more suitable for monitoring large-scale infrastructures. In this study, we employed the Sentinel-1 data to monitor the canal of the Middle Route of the SNWD Project within Henan Province. The deformation rates along the canal were obtained by using persistent scatterer InSAR, from which a total of 20 deformed canal sections and seven suspected deformed canal sections were identified. Among them, the Shahe aqueduct is overall stable except for the Shahe Beam Aqueduct and Lushanpo Landing Aqueduct. The Yuzhou-Changge canal passes through a subsidence funnel with a maximum deformation rate of about &#x2013;20 mm&#x002F;year. The InSAR-derived deformation coincides well with the <i>in-situ</i> leveling measurements over the Yuzhou-Changge canal. Their correlation is 0.95 and the root mean square error of their differences is 2.41 mm&#x002F;year. The results demonstrate the effectiveness of satellite InSAR for monitoring large-scale hydraulic engineering. It can be combined with ground leveling to achieve overall investigations and detailed monitoring, largely improving the efficiency and cost of the current ground monitoring system.

Environmental implications from the priority pollutants screening in impoundment reservoir along the eastern route of China's South-to-North Water Diversion Project

Screening priority pollutants from vast anthropogenic contaminants discharged into aquatic environment is urgent for protecting water quality definitely. The multi-criteria scoring method involved in the occurrence (O), persistence (P), bioaccumulation (B), ecological risk (Eco-T), and human health risk (Hum-T), was established for pollutants prioritization in waters and applied in Dongping Lake, the final impoundment reservoir along the eastern route of China's South-to-North Water Diversion Project (SNWDP). A total of 170 chemicals including heavy metals (HMs), volatile organic chemicals (VOCs), polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), phthalate esters (PAEs), and antibiotics (ANTs) were investigated as the candidates. Accordingly, 42 chemicals including 8 PAEs, 7 OCPs, 7 PCBs, 5 PAHs, 13 HMs, and 2 VOCs were made up the list of priority pollutants for Dongping Lake, suggesting the necessity of routine monitoring high priority groups and revising the existing list. Multiple risk assessment indicated higher ecological and human health risks induced by HMs than by organic pollutants. Spatial distribution of risks stressed the retention of toxic organic chemicals by the lake body and the accumulation of HMs along the transfer route, respectively, thus triggering ecosystem responses and potential effects on the water-receiving areas as expected.

Efficiency analysis of metacoupling of water transfer based on the parallel data envelopment analysis model: A case of the South–North Water Transfer Project-Middle Route in China

The deepening of globalization and the rapid socio-economic development have contributed to the increasing demand for water resources, which intensified the problem of water shortage. Cross-regional water transfer is an effective measure to alleviate the contradiction between the supply and demand of regional water resources. However, due to the strong interaction among the water source area, water-receiving area and the downstream of the water source area in the water transfer project, how to measure the impact of metacoupling of water transfer remains to be explored. Firstly, this study constructs the input and output indicators of the model. The input indicators are mainly based on Water Transfer, while the output indicators emphasize the economic, social and ecological benefits of water used by provinces and cities, which facilitates the measurement of the metacoupling. Secondly, the evaluation framework for the parallel data envelopment analysis (DEA) model of metacoupling of water transfer was built from the perspective of efficiency. This framework divides the metacoupling of the water transfer project into intracoupling, pericoupling and telecoupling, and opens the internal structure of the traditional DEA system. By calculating the efficiency of each system and using the weighted average method, the overall efficiency and the efficiency of each part of water transfer can be evaluated. In addition, the overall efficiency can be optimized by adjusting the proportion of water resources. The main results are: (Ⅰ) The overall water efficiency of the Middle Route of China's South-North Water Transfer Project is high, at above 0.7, with intracoupling(0.605)<pericoupling(0.818)<telecoupling(1.088). (II) The water source area and the downstream area have the most obvious improvement in water consumption efficiency, while the northern water-receiving areas have shown small improvement. The evaluation of water utilization efficiency can help to identify problems such as irrational water use structure, inefficient water consumption and water waste, and the water utilization efficiency can be improved by optimizing the proportion of water transfer.

Determination of the optimal ecological water conveyance volume for vegetation restoration in an arid inland river basin, northwestern China

Overexploitation of water resources has led to severe ecological degradation and even desertification in some arid inland river basins, northwestern China. To alleviate or restore the degraded vegetation ecosystem, ecological water conveyance (EWC) has become an important and effective measure. Scientific assessment of the impact of EWC on vegetation restoration and determination of the corresponding optimal EWC volume (EWCV) are important to formulate rational ecological water management. In this study, long time series normalized difference vegetation index (NDVI) was used to extract the restored vegetation area in Qingtu Lake area, a terminal lake in inland Shiyang River basin, northwestern China. The relationship between restored vegetation coverage and EWC was explored to determine the optimal EWCV. The restored vegetation area (RVA) increased dramatically in the first five years and became stable from 2016. The time lag of the response of RVA increase to EWC was about 2 years. A bell-shaped function between RVA and groundwater depth was obtained based on the results from Unmanned Aerial Vehicle (UAV) and micro terrain of the lake area. Based on the fitted function, five groundwater depth thresholds were obtained. The optimal groundwater depth in the hydrometric station was 2.91 ± 0.09 m for the maximal RVA (17.08 ± 3.25 km2). A polynomial function between the yearly EWCV and groundwater depth was developed and the EWCV thresholds corresponding to the groundwater depth thresholds were estimated. The optimal EWCV into Qingtu Lake was 2224.4 × 104 m3 for the maximal RVA. The correspondingly optimal EWCV from Hongyashan Reservoir was 3271.4 × 104 m3. The spatial distribution patterns of remotely sensed water surface and NDVI suggested that expanding the water-receiving area of conveyed water was useful to improve the vegetation growth. This study provides a reference for assessing the impact of EWC on vegetation restoration and determining the correspondingly optimal EWCV in arid inland river basins.

Ecological Compensation Standard of a Water-Receiving Area in an Inter-Basin Water Diversion Based on Ecosystem Service Value and Public Willingness: A Case Study of Beijing

Ecological compensation has recently gained significant attention as an economic incentive promoting natural resource management. However, there remain several challenges to its application. A key issue is the lack of a method clearly define the standard of ecological compensation. This study established an accounting methodology for the ecological compensation standard for the water-receiving area in an inter-basin water diversion in China. Beijing, a major water-receiving area of the South-to-North Water Diversion Project, was used as an example of the application of this approach. First, the evaluation index of ecosystem service value of the water-receiving area was selected, then, emergy theory was used to calculate the increment of ecological service value based on the characteristics of each indicator. The ecological service value due to the project was calculated to be 3.898 billion RMB, while the willingness-to-pay by the public was estimated at 915 million RMB. Therefore, the increment of ecological service value was the highest standard of compensation, and the public’s willingness-to-pay was the lower limit of ecological compensation. The final compensation standard can be determined through negotiation between suppliers and beneficiaries under the leadership of relevant governments and water-transfer authorities. Thus, this study aimed to provide a scientific basis for the construction of diversified ecological compensation mechanisms and promote sustainable development of the region.

Optioning Water Rights: A Potential Alternative to the Hanjiang-Weihe River Water Transfer Project, China

China has started shifting from relying on supply management to demand management strategy in addressing its water shortage problems. Water option, a financial derivative for water commodity, has been utilized to manage water demands in the United States and Europe since the 1990s but is still novel to China. In this study we analyzed the pros and cons of China’s existing system for water rights transfers and proposed an alternative, flexible trading instrument-water options for China. Incorporating the uncertainty to water option pricing, this study first conducted an empirical analysis of the water option in the water-receiving area of the Hanjiang-Weihe River Transfer Project of China, and then evaluated the benefits of the water option applications. Results show that water option trading can bring water cost saving and increase the potential industrially added value for industrial enterprises in the receiving area, and trading of short-and-medium term water options is more favorable than the long-term water options trading. The novel water option trading proposed in this study, once verified through pilot studies, will be helpful in addressing water shortage problems in China.

Research on water resources dispatch model based on improved genetic algorithm – water resources dispatch model

Abstract According to the research on reservoir water resources scheduling and distribution, the aim is to balance the water supply and demand in each period, and consider the total water supply and the annual external water withdrawal of the reservoir in each period as water rights. The decision-making variables are provided for the water supply of the reservoir in this paper, so that water demand of the water-receiving area can be better met to alleviate the water shortage at various stages and realize the effective use of water resources. Moreover, through the constraints of reservoir operation rules and other constraints, a mathematical model is established for optimal operation of water resources in the reservoir system. Meanwhile, optimized genetic algorithms are applied to solve the model according to the characteristics of the model. After simulation tests, compared with the traditional linear binary algorithm used in the reservoir, the improved genetic algorithm studied in the paper improves the accuracy of data calculation and data convergence, which proves that the research results of the paper provide theoretical and practical significance for improving the level of reservoir water resources management and solving the problem of optimal water resources scheduling.

Coincidence probability of streamflow in water resources area, water receiving area and impacted area: implications for water supply risk and potential impact of water transfer

Abstract Under changing environment, the feasibility and potential impact of an inter-basin water transfer project can be evaluated by employing the coincidence probability of runoff in water sources area (WSA), water receiving area (WRA), and the downstream impacted area (DIA). Using the Han River to Wei River Water Transfer Project (HWWTP) in China as an example, this paper computed the coincidence probability and conditional probability of runoff in WSA, WRA and DIA with the copula-based multivariate joint distribution and quantified their acceptable and unfavorable encounter probabilities for evaluating the water supply risk of the water transfer project and exploring its potential impact on DIA. Results demonstrated that the most adverse encounter probability (dry–dry–dry) was 26.09%, illustrating that this adverse situation could appear about every 4 years. The acceptable and unfavorable probabilities in all encounters were 44.83 and 55.17%, respectively, that is the unfavorable situation would be dominant, implying flood and drought risk management should be paid greater attention in project operation. The conditional coincidence probability (dry WRA &amp; dry DIA if dry WSA) was close to 70%, indicating a requirement for an emergency plan and management to deal with potential drought risk.

Occurrence and distribution of antibiotic resistance genes in lakes and reservoirs from water-receiving area of Eastern Route of the South-to-North Water Diversion Project, Northern China

Abstract To characterize antibiotic resistance genes (ARGs) in surface waterbodies in Shandong Province, and to understand the occurrence, diversity and resistance mechanism of ARGs, nine aquatic ecosystems were selected and evaluated regarding occurrence of ARGs in the period from 2018 to 2019. Thirty-three types and 242 subtypes of ARGs were detected in the nine waterbodies with the most subtypes in Wohushan (242) and Jihongtan (235), and the fewest ARGs in Datun (213) and Mishan (221). Among the top nine ARG types, MacB, BcrA, CarA and TetW were the dominant ARGs in these samples. Four groups of the study sites were distinguished by cluster analysis, indicating different distribution characteristics of ARGs in these waterbodies, and regional differences in ARG contamination. Efflux pumps were the predominant resistance mechanism in all the waterbodies in terms of both subtype number (49.2%) and abundance (70.4%), followed by operon, antibiotic inactivation and others. Our findings provide comprehensive information to better understand the contamination level of ARGs on a local level as well as for global considerations, and may be practically helpful for the prevention and control of ARG pollution.

Water transfer imposes hydrochemical impacts on groundwater by altering the interaction of groundwater and surface water

How the water transfer imposes impacts on the groundwater in the water-receiving area is still unknown. Here, we employed hydrometric observations, hydrogeochemical analyses and data analysis methods to address this issue, taking one of the Yellow River water transfer project of China for example. We found that the interaction between river and groundwater is totally changed by the water transfer and the impact of the water transfer on groundwater is confined by the high stream gradient. With the water transfer, the natural annual pattern of rainy-season high river flow is inversed with low flow in rainy seasons and high flow during the water transfer. Moreover, the river stage is always higher than the groundwater level throughout the year. The usual bidirectional river–groundwater hydraulic gradient is altered to be a gradient always away from the river. The groundwater directly connects with the river water. The regime of groundwater level follows the change of the river stage, even in the valley side. A long-term standing groundwater mound is formed within the riparian zone due to the continuous recharge from the water-receiving river. The transferred Yellow River water is hydrochemically featured by high EC value and concentrations of Na+ and Cl−. The hydrochemical features of the water-receiving river are obviously changed by the transferred Yellow River water. The hydrochemical impact of the river on the groundwater is mainly confined to the riparian zone and some low-reach transections, despite of the dominated control of the river on the valley groundwater table. The high stream gradient trends to produce the downstream groundwater flow and hinder the lateral groundwater flow from river to valley sides in the upper reaches, responsible for the confined impact on groundwater. Our study highlights that the stream gradient could obviously influence the river water and groundwater interaction promoting or confining the impact of river water on groundwater.

Variations in stable carbon and nitrogen isotopes of particulate organic matter in surface waters of water-receiving area of Eastern Route of South-to-North Water Transfer Project, China.

The purpose of this study was to assess the water quality and variations in stable carbon and nitrogen isotopes of particulate organic matter (δ13CPOM and δ15NPOM), as well as to evaluate the sources of carbon and nitrogen that contribute to the POM pools in lakes and reservoirs located in the water-receiving area of the Eastern Route of South-to-North Water Transfer Project (SNWTP) in Northern China. During each season from October 2013 to July 2014, samples of POM from 14 lakes and reservoirs in Northern China were collected. The lakes and reservoirs were meso-eutrophic with considerably high brackish ions (SO42-, 173mg/L; Cl-, 296mg/L) in Yangtze River lake, and high total nitrogen: total phosphorus ratio (averaged with 772) or dissolved inorganic nitrogen: soluble reactive phosphorus molar ratios (averaged with 1077) in mountainous reservoirs. The δ13CPOM, δ15NPOM, carbon to nitrogen (C/N) ratios showed significant seasonal variation, with ranges of - 32.5 to - 17.4‰, - 3.6 to 13.5‰, and 5.1-13.2, respectively, while they were hard to be distinguished among types of water sources. Principal component analysis (PCA) indicated that brackish ions, nutrients, and their molar ratios were the main factors influencing variations in δ13CPOM and δ15NPOM. δ13CPOM and C/N ratios suggested autochthonous primary production mainly contributed to POM during from April to October, while exogenous organic matter might mainly contribute these carbon pools in January. The low values of δ15NPOM (< 0‰) and negative correlation between δ15NPOM and TN suggested discharge of agricultural waste water (e.g., fertilizers, irrigation tailwater) in Bailanghe, Xinan, and Taihe Reservoir during the fertilization season, while higher values indicated domestic sewage input to waterbodies (e.g., Mishan, Gengjing, Donghai Reservoir). Our results suggested that the aquatic ecosystem in water-receiving area of SNWTP would be potentially affected by the inter-basin water diversion, and thus, ecosystem-based strategies were also presented accordingly.

Assessment of the Socio-Economic Impact of a Water Diversion Project for a Water-Receiving Area

Assessment of the Socio-Economic Impact of a Water Diversion Project for a Water-Receiving Area

A multi-objective water trading optimization model for Henan Province's water-receiving area in the Middle Route of China's South-to-North Water Diversion Project

Abstract Water trading is an effective method for solving regional water shortage problems and addressing the uneven spatiotemporal distribution of water resources. Therefore, taking the Middle Route of China's South-to-North Water Diversion Project (MR-SNWDP) as the research object, we present a study on a feasible water trading scheme in the water-receiving area of Henan Province. First, the tradable water of each calculation unit in the water-receiving area was calculated by analyzing the water-saving potential of different industries. Second, a multi-objective optimization model for trading water between different regions was developed, taking the largest social and economic benefits of the water-receiving area as the objective function. Finally, non-dominated sorting genetic algorithms were used to solve this optimization model, and an optimal scheme for water trading was proposed. The simulated results of the optimal scheme indicate that the total water shortage of the water-receiving areas will decrease by 650.69 million m3, and there will be a surplus of 14.98 million m3 of water, and the gross national product will increase by RMB 130.5 billion at a rate of 5.2%. This demonstrates that the water-receiving areas of Henan Province can effectively alleviate local water shortages by trading water without increasing external water supplies.

Effects of the South-North Water Diversion Project on the Water Dispatching Pattern and Ecological Environment in the Water Receiving Area: A Case Study of the Fuyang River Basin in Handan, China

Inter-basin water transfer projects are widely used in water-stressed areas. North China is facing severe imbalance between water demand and water supply. The South-to-North Water Diversion (SNWD) Project was built to transfer water from the Yangtze River Basin to the Hai River Basin. The Fuyang River Basin in the southern part of the Hai River Basin, passing through the Handan city, was chosen as the study area. To identify the effects of the SNWD Project on the water-receiving area, this paper used the decision support system AQUATOOL to simulate the water-dispatching scheme while using the water from the SNWD Project for domestic need in different level years. The results indicate that the SNWD Project provided 128.32 × 106 m3 of water in a wet year, 109.88 × 106 m3 in a normal year and 135.14 × 106 m3 in a dry year to this area. The added quantity of recycled water is 56.75 × 106 m3, 50.59 × 106 m3 and 57.52 × 106 m3, respectively. The water shortage in normal years was covered by the SNWD Project and the water shortage in dry years was reduced by 62.4%. Local environment was improved because of the SNWD Project, i.e., the SNWD water replaced and reduced the use of groundwater and increased the inflow to the Fuyang River and the Yongnian Wetland by increasing the recycled water. This research has demonstrated the SNWD Project has started to play a key role in securing water use and improving the environment in the water-receiving area since its completion in 2014.

Impacts of the eastern route of the South-to-North Water Diversion Project emergency operation on flooding and drainage in water-receiving areas: an empirical case in China

Abstract. The water levels of lakes along the eastern route of the South-to-North Water Diversion Project (ER-SNWDP) are expected to rise significantly and subsequently affect the processes of flood control and drainage in corresponding lake basins. However, few studies have focused on the impacts of inter-basin water diversion on the flood control and drainage of water-receiving areas at the lake basin scale. Using MIKE software, this paper builds a coupled hydrodynamic model to address the existing literature gap regarding the impacts of inter-basin water diversion on the processes of flood control and drainage in a water-receiving lake basin, and it considers the many types of hydraulic structures in the model. First, a flood simulation model was constructed to simulate the complex movement of water transferred by the ER-SNWDP, by waterlogging in the lakeside area around Nansi Lake (NL), and water in NL and its tributaries. The ER-SNWDP was also considered in the model. Second, the model was calibrated and verified with measurement data, and the results showed that the model was efficient and presented a Nash–Sutcliffe efficiency coefficient (NSE) between 0.65 and 0.99. Third, the processes of flooding and draining in the lakeside area of NL were simulated under different water diversion and precipitation values. Finally, the impacts of the emergency operations of the ER-SNWDP on flood control and waterlogging drainage in the lakeside area of NL were analysed based on the results from the proposed model, and some implications are presented for the integrated management of inter-basin water diversion and affected lakes.

Reservoir Operation Policy based on Joint Hedging Rules

When the water supply capacity of the reservoir is small, hedge rule (HR) can be applied to reduce the risk of unacceptably large damage from water shortage during drought. Moreover, in water-receiving areas of water diversion project, it is important to reduce transfer based on HR when the water-receiving area is in a wet period so as to reduce the water transfer cost. This paper improved the traditional HR and proposed a new kind of hedging rule named joint hedging rule (JHR). JHR was applied to Yuqiao Reservoir of Tianjin in China and was compared with HR and standard operation policy (SOP) as two control groups. The result indicates that JHR performs better than HR and SOP, which cannot only mitigate the risk of unacceptably large damage from water shortage by one hedge process but also reduce the transferred water by another hedge process. In addition, the number of days of different water shortage, the storage ratio at the end of the year, and transferred water result indicates that JHR is of high reliability and practicability.