Inter-basin Water Transfer Projects Research Articles

A nature-based reservoir optimization model for resolving the conflict in human water demand and riverine ecosystem protection

Although construction of reservoirs and dams is one of the most common approaches to satisfy water demand and alleviate water scarcity, this approach severely affects river ecosystems. The most direct impact of human activities on rivers, for instance, regulating river can lead to degraded riverine ecosystems as part of the hydrological alteration. This paper determines the available ratio of water resource of natural or semi-natural rivers for ecological feasible regions using a method that transcends the traditional perspective of designed environmental flow. Our framework involves a modified percent of flow approach to identify the ecological feasible region of water resources utilization, which sequentially acts as a constraint for a reservoir optimization model based on the Cuckoo Search algorithm to obtain an optimal diversion process. Indicators of the hydrological alteration statistical method and the histogram matching approach are used to examine the framework's performance. The Han to Wei inter-basin water transfer project of China is selected as a case study. Results indicate that: (1) the allowable diversion rate with this modified percent of flow approach is more effective for reducing interference of diversion on the ecosystems than the conventional planned diversion rule; water demand, however, cannot be satisfied by the allowable diversion rate; (2) ecological feasible region is an accessible constraint for reservoir operation model, and the optimal diversion rate of such model is a trade-off output between the human water demand and the riverine ecosystems protection; and (3) increased allowable diversion rates alter flow indicators including the February flow, 30-day minimum flow, and low pulse count more appreciably than does the optimal diversion rate. This study provides key insights on how to achieve a trade-off between human water demand and riverine ecosystems protection, therefore contributing to the local sustainable development of social economy and ecological environment.

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 Inter-Basin Water Transfer Projects on Optimal Water Resources Allocation in the Hanjiang River Basin, China

Inter-basin water transfer project is an effective engineering countermeasure to alleviate the pressure of water supply in water-deficient areas and balance the uneven distribution of water resources. To assess the impacts of inter-basin water transfer projects on optimal water resources allocation, an integrated water resources management framework is proposed, and is applied to the middle and lower reaches of the Hanjiang River Basin in China. Firstly, future water demands are analyzed as inputs. Then, a multi-objective water resources allocation model is formulated mitigating the negative impacts of water transfer projects on downstream water quantity and quality by using the non-dominated sorting genetic algorithm-II (NSGA-II). Finally, the indicators of water supply reliability, vulnerability and resilience are evaluated under different scenarios of inter-basin water transfer projects. The results indicate that: (1) the reliability and resilience of the water donor system will be gradually reduced while the vulnerability will be increased with the expansion of water transfer projects and the increase of water demand, (2) water supply risk is likely to increase in all zones (because zones at the boundary cannot obtain sufficient water due to limitations of local inflow and reservoir operation, while the amount of water available in the zones along the mainstream river is directly decreased by the water transfer projects), (3) more water supply measures and compensation measures will need to be implemented in the water donor areas. The framework proposed in this study to evaluate the comprehensive impact of inter-basin water transfer projects is conducive to water resources management.

Environmental Flow Assessment Considering Inter- and Intra-Annual Streamflow Variability under the Context of Non-Stationarity

A key challenge to environmental flow assessment in many rivers is to evaluate how much of the discharge flow should be retained in the river in order to maintain the integrity and valued features of riverine ecosystems. With the increasing impact of climate change and human activities on riverine ecosystems, the natural flow regime paradigm in many rivers has become non-stationary conditions, which is a new challenge to the assessment of environmental flow. This study presents a useful framework to (1) detect change points in runoff time series using two statistical methods (Mann-Kendall test method and heuristic segmentation method), (2) adjust data of the changed period against the original flow series into a stationary condition using a procedure of reconstruction; and (3) incorporate inter- and intra-annual streamflow variability with adjusted streamflow to evaluate environmental flow. The Jialing to Han inter-basin water transfer project was selected as the case study. Results indicate that a change point of 1994 was identified, revealing that the stationarity of annual streamflow series is invalid. The variations of reconstructed streamflow series are roughly consistent with original streamflow series, especially in the maximum/minimum values and rise/fall rates, but the mean value of reconstructed streamflow series is increased. The reconstructed streamflow series would further serve to eliminate the non-stationary of original streamflow, and incorporating the inter- and intra-annual variability would upgrade the ecosystem fitness. Selecting different criteria for the conservation of riverine ecosystems can have significantly different consequences, and we should not focus on the protection of specific objectives that will inevitably affect other aspects. This study provides a useful framework for environmental flow assessment and can be applied to a wide range of instream flow management approaches to protect the riverine ecosystem.

Hydrochemical characteristics and quality evaluation of groundwater in terms of health risks in Luohe aquifer in Wuqi County of the Chinese Loess Plateau, northwest China

Groundwater is the main source of water for domestic and agricultural purposes in Wuqi County on the Loess Plateau. The present study was carried out to assess the hydrochemical characteristics and quality of groundwater in the Luohe aquifer, which is a crucial aquifer for water supply. For this study, 22 groundwater samples and 6 surface water samples were collected for analysis. Hydrochemistry and hydrochemical facies of groundwater were analyzed using statistical analysis and Tri-linear diagram. Gibbs diagram, correlation analysis and bivariate plots were used to investigate the natural evolution mechanisms of groundwater and surface water. Potential health risks of nitrate and Cr6+ through drinking water ingestion for adults and children were estimated. The results show that the major hydrochemical facies is Cl·SO4-Na, mixed Cl·SO4·HCO3-Na and SO4·Cl-Mg·Na types, and high concentration of Na+ is a remarkable feature of groundwater in the study area. Groundwater chemistry evolution is affected by rock weathering and evaporation. The high concentrations of Na+, SO42- and TDS suggest that groundwater is not suitable for irrigation purposes. According to WQI values, above 80% of the groundwater samples are fair quality water. It is also found that the groundwater of the study area is contaminated with nitrate and Cr6+. Children are at higher health risk than adults. Multiple measures such as establishing new centralized water supply sources and inter-basin water transfer projects have also been proposed in this study to guarantee the safety of sustainable groundwater supply.

Determination of drought limit water level of importing reservoir in inter-basin water transfer project under changing environment

Drought occurrence and its related impacts are a major concern in many basins throughout the world. Reservoirs play a very important role in drought resistance. Compared with the reservoir flood limit water level, the drought limit water level belongs to a new concept. This paper took the Yuqiao reservoir as the study area and proposed a new method to determine the drought limit water level under changing environment. Firstly, the Mann-Kendall (M-K) method and cluster analysis method were employed to test the trend and change point of the series based on the runoff series of Yuqiao reservoir. On this basis, the runoff frequency curve and design runoff process under current condition were obtained by Pearson-III frequency analysis. Secondly, copula function was used to analyze the synchronous-asynchronous encounter probability of rich-poor runoff of Yuqiao reservoir and Panjiakou reservoir. The available transferred volume of Yuqiao reservoir in dry year was analyzed. Finally, according to the runoff and available transferred volume, the total inflow of Yuqiao reservoir in dry season was calculated. Combining water demand and total inflow of Yuqiao reservoir, the drought limit water level was calculated by month to month. The study results can provide necessary technique support for reservoir drought emergency management.

Stability Analysis of Stakeholders’ Cooperation in Inter-Basin Water Transfer Projects: a Case Study

This study investigates the conflict resolution among different stakeholders in a water transfer project. The portion of the Beheshtabad Water Transfer Project in Iran which aims to convey water from the Karun Basin to the Gavkhuni Basin is used as a case study. In this process, the initial water allocation scheme is initially determined through simulation in MODSIM ignoring the water transfer project. Then, the concepts of cooperative and non-cooperative games are used to resolve the conflict among the stakeholders. The profits of water transfer project and the payoffs for each player are calculated using an optimization model that optimizes the allocation of the conveyed water. The results of the conflict resolution model show that bilateral cooperation is the best strategy the players may adopt. In the non-cooperative model, it is found that a water transfer agreement that is incentivized by an average payment of 250.66 million US$ as compensation from the Gavkhuni basin to the Karun basin puts both basins at equilibrium with a Pareto optimal condition; in this case, none of the players will be willing to abandon the cooperation without regret. In the cooperative approach, cooperation is found to be beneficial to all the players involved.

An Optimal Model for Water Resources Risk Hedging Based on Water Option Trading

The uncertainty of forecasted runoffs brings risks of water shortages to water users in the intake area of long-distance water transfer projects, and the uncertainty of spot market prices may cause them to buy water at high prices. In order to hedge these risks, this paper proposes a risk hedging model for decision-making in water option trading from the viewpoint of water users. With the objective of maximizing the expected revenue of water users, the proposed model was solved by an analytical method and an optimal water option strategy was obtained for the users. The proposed model is applied to an intake area of an inter-basin water transfer project in China. The results show that the proposed water option trading model can provide water users with an optimal option strategy. The optimal options trading strategy can effectively reduce the risk caused by the uncertainties of forecasted runoffs and water prices. We also explored the influence of the uncertainty degree of the forecasted runoffs and water price on the option trading strategy. The results show that the expected revenue of water users increases as the variances of the errors of forecasted runoffs and water prices increase.

Environmental flow modelling of the Chalakkudi Sub-basin using ‘Flow Health’

Ecohydrological modelling and prescribing environmental flows (e-flows) is significant in the Integrated Water Resources Management (IWRM) practice. However, for many river basins, there is lack of data on ecosystems and on the relationships between e-flows and ecosystem functioning. This lack of sufficient ecosystem data is mostly addressed in ecohydrological modelling by using hydrological metrics as surrogates of river ecosystem. In this study, we are demonstrating how it helps e-flows modelling and real-life management decisions underway with respect to Inter-basin Water Transfer (IBWT) projects. Desktop model ‘Flow Health’ is used here to design e-flows regime for Chalakkudi Sub-basin in Southern Peninsular India. Chalakkudi Sub-basin is over abstracted with six large dams built as components of the Parambikulam Aliyar Project (PAP), Asia's largest IBWT network. The monthly e-flow regimes required to maintain alternate levels of ecosystem conservation are estimated in this paper. The additional flood flow volume required for these alternate levels is also discussed. The results are useful in the stakeholder engagement process for informed decision-making on e-flows and redefining the IBWT operations within a broad framework of IWRM.

Quantitative assessment of the impact of an inter-basin surface-water transfer project on the groundwater flow and groundwater-dependent eco-environment in an oasis in arid northwestern China

Inter-basin water transfer projects (IBWTPs) can involve basins as water donors and water receivers. In contrast to most studies on IBWTPs, which mainly impact the surface-water eco-environment, this study focuses on the impacts of an IBWTP on groundwater and its eco-environment in a water donor basin in an arid area, where surface water and groundwater are exchanged. Surface water is assumed to recharge groundwater and a groundwater numerical simulation model was constructed using MODFLOW. The model was used to quantitatively evaluate the impact of an IBWTP located in the upstream portion of Nalenggele River (the biggest river in the Qaidam basin, Northwest China). The impact involved decrease in spring flow, drawdown of groundwater, reduction in oasis area, and an increase in species replacement of oasis vegetation in the midstream and downstream of the river. Results show that the emergence sites of springs at the front of the oasis will move 2–5 km downstream, and the outflow of springs will decrease by 42 million m3/a. The maximum drawdown of groundwater level at the front of the oasis will be 3.6 m and the area across which groundwater drawdown exceeds 2.0 m will be about 59.02 km2, accounting for 2.71% of the total area of the oasis. Under such conditions, reeds will gradually be replaced by Tamarix, shrubs, and other alternative plant species. These findings have important implications for the optimization of water resource allocation and protection of the eco-environment in arid regions.

Inter-Basin Water Transfer Green Supply Chain Equilibrium and Coordination under Social Welfare Maximization

The inter-basin water transfer (IBWT) projects have quasi-public-welfare characteristics, whose operations should take into account the water green level (WGL) and social welfare maximization (SWM). This paper explores the interactions between multiple stakeholders of an IBWT green supply chain through the game-theoretic and coordination research approaches considering the government’s subsidy to the WGL improvement under the SWM. The study and its findings complement the IBWT literature in the area of the green supply chain and social welfare maximization modeling. The analytical modeling results with and without considering the SWM are compared. A numerical analysis for a hypothetical IBWT green supply chain is conducted to draw strategic insights from this study. The research results indicate that (1) If the SWM is not considered, coordination strategy could effectively improve the operations performances of the IBWT supply chain and its members, the consumers’ surplus, and the social welfare when compared with the equilibrium strategy; (2) If the SWM is considered, the IBWT green supply chain and its members have a strong intention to adopt the equilibrium strategy to gain more profits, while the government has a strong intention to encourage the IBWT green supply chain and its members to adopt the coordination strategy to maximize social welfare with a smaller public subsidy; (3) The government’s subsidy policy should be designed and provided to encourage the IBWT green supply chain and its members to improve WGL and pursue the SWM, and a subsidy threshold policy can be designed to maximize social welfare with a lower subsidy budget: only when the IBWT green supply chain and its members adopt the coordination strategy can they get a subsidy from the government.

Decline of N and P Uptake in the Inner Protection Zone of a Terminal Reservoir during Inter-Basin Water Transfers

Inter-basin water transfer projects are designed to relieve water scarcity around the world. However, ecological problems relating to reductions in protection zone functions can occur during inter-basin transfers. This paper uses the largest inter-basin water transfer project in the world, namely, the South-to-North Water Transfer Project (SNWTP) in China, as an example to analyze the variation of Miyun Reservoir’s inner protection zone functions when water is transferred. Specifically, a riparian model (RIPAM) coupled with remote sensing data were used to calculate the nitrogen (N) and phosphorus (P) losses due to plant uptake, and these results were validated by in situ survey data. Then, correlations between water levels and N and P removal were analyzed. The results show that water table disturbances resulting from elevated water levels strongly influence the growth of plants and have obvious negative impacts on N and P removal in the inner protection zone. With the implementation of the middle route of the SNWTP, the water level of Miyun will rise to 150 m in 2020, and subsequently, the total net primary productivity (NPP) could decline by more than 40.90% from the level in 2015, while the N and P uptake could decline by more than 53.03% and 43.49%, respectively, from the levels in 2015, according to the modeling results. This will lead to declines in the inner protection zone’s defense effectiveness for N and P interception and increases in risks to the security of water resources. The results of this study provide useful knowledge for managing the defense function of the terminal reservoir’s inner protection zone and for ensuring that water quality is maintained during the diversion process.

Study on Long-term Water Quality Protection Mechanism Framework of Inter-basin Water Diversion Protect

With the increasing and complicated contradiction between the supply and demand of water resources in recent years, a number of inter-basin water diversion projects have been built in various places in China. The water supply objects of the inter-basin water diversion projects are mostly industrial and domestic water, and the water quality is closely related to the success or failure of the water transfer project, which makes it necessary to establish a long-term water quality protection mechanism. On the basis of analyzing major issues in water quality protection in inter-basin water transfer projects, a long-term mechanism framework for water quality protection was established and elaborated from the aspects of institutional system, water quality goals, risk management, guarantee conditions, feedback mechanism, technical evaluation, administrative assessment, public participation, incentive measures, aiming to provides reference for the water quality safety inter-basin water diversion projects.

跨流域调水工程绿色供应链管理：动因、内涵、要素与机制

跨流域调水工程绿色供应链管理：动因、内涵、要素与机制

Impact on operation of the Middle Route Project of South-to-North Water Diversion

The inter-basin water transfer project is one of the most important means to solve the uneven distribution of water resources in time and space, rationally allocate water resources, and promote the construction of water ecological civilization. Research on the operation impact and channel hydraulic response is meaning for the safe operation of long-distance water conveyance canals. Taking the Middle Route Project (MRP) of South-to-North Water Diversion (SNWD) as example, this paper built the onedimensional steady and unsteady flow model and investigated the impact of roughness change, emergency rescue technology and equipment, and sluice control failure. Results showed that increased roughness decreased the water diversion efficiency of MRP to some degree. The emergency rescue technology and equipment occupied the channel section and declined flow capacity. The occurrence of sluice control failure relatively played an increasing impact on upstream water level and a decreasing impact downstream water level and flow discharge. The impact of the above scenarios on the scheduling operation can be reduced to a certain extent by regular cleaning and maintenance, development of rational water emergency rescue project, development of staff skill, etc. This research can provide support for safe operation and regulation of the MRP of SNWD.

Study on water resources optimal regulation of inter-basin water transfer project

Water resources optimal regulation is an important means to mitigate the shortage of water resources and promote social and economic sustainable development in regions or watershed. With the rapid development of urban population and industrial and agricultural production in recent years, the shortage of water is becoming more and more serious in Jiaodong area. The four regions with serious water shortage including Weifang, Qingdao, Yantai and Weihai in Jiaodong area are the typical research areas. In combination with the water transfer project of Yellow river to Qingdao and the south-to-north water transfer project, the water diversion is carried out to alleviate the contradiction between water supply and demand of Jiaodong area. The year of 2014 deemed as the base year and the years of 2020 and 2025 are the planning years. Based on the supply and demand analysis of water resources, an optimal regulation model is built with the minimum total water shortage considering the constraints of water supply capacity of project, water distribution capacity and minimum water supply of bleeds and so on. The optimal regulation schemes are obtained by solution model using MATLAB programming. The results show that water shortage rate of the four cities decreases significantly in annual regulation. For different planning years, guarantee rate of 50%, 75% and 95%,the total water shortage rate will be reduced by 15.35%、15.75% and 16.85% respectively in 2020, and in 2025the total water shortage rate will be reduced by 13.27%、13.26% and 14.19% respectively. Therefore the water resources optimal regulation of inter-basin water transfer project can effectively mitigate water scarcity and the contradiction between water supply and demand in Jiaodong area.

Calculation of Thallium's toxicity coefficient in the evaluation of potential ecological risk index: A case study

As a common pollutive metal element, Tl is very biotoxic. The potential ecological risk index (RI) proposed by Håkanson is one of the commonest methods for evaluation of ecological risk of a metal in sedimentary environment of a water body. According to the calculation principle proposed by Håkanson, the toxicity coefficient of Tl was calculated, and determined as 10 in this paper. In addition, the environmental risk of Tl in the surface sediment of the Beijing-Hangzhou Grand Canal (Zaozhuang Section) was evaluated by RI method, enrichment factor method, etc. The South-to-North Water Diversion Project which benefits four billion people is the largest inter-basin water transfer project in China. The Zaozhuang Section is a significant water conveyance line of this project. We found that the Tl concentrations were 0.46–0.70 μg g−1 with the mean value of 0.61 μg g−1 and were higher than the local background value. The highest contents of Tl occurred in the middle of Zaozhuang section and Tai'erzhuang District, but the enrichment degree of it was much higher in the entrance of Nansihu Lake. The grain size and Al oxides/hydroxides were main factors which controlled the distribution of Tl. Analysis of enrichment factors indicated that Tl in sediments possessed obvious source of human activities which were mainly from combustion of fossil fuels such as coal and mining of mineral resources. As a whole, however, the research region has low Tl content, so Tl has a small probability of environmental pollution.

Research on the Comprehensive Effect of Ecological Regulation in the Mainstream of Weihe Basin

The Weihe River is the largest tributary of Yellow River in China. Due to the decrease in water resources and social-economic development, water resources situation in the Weihe River Basin is more serious now than ever before. Water use for the hydro-ecological system has been obviously decreased because of the reduction in water resources and the increase in social-economic water consumption. Reservoir ecological regulation is an effective measure to preserve river health and to realize man-water harmonization. Based on ecological regulation theory, principles of ecological regulation were presented according to the different levels of social-economic development in the Weihe River Basin. The regulation approaches for ecological water use were analyzed in terms of water saving, recycled water reuse, joint regulation of reservoirs, conjunctive operation of surface water and groundwater, controlling intake of hydropower and inter-basin water transfer project. Water regulation model of Weihe River Basin was constructed. Water regulation scenarios were set. With the ecological basic flow (EBF) targets of the key sections on the mainstream, the balance of water supply-demand, water supply for important reservoirs and the monthly guarantee rate of ecological flow were analyzed. Although further study is desired, the results are believed to be of great referential value to sustainable development in the basin.

The assessment of the changes of biomass and riparian buffer width in the terminal reservoir under the impact of the South-to-North Water Diversion Project in China

Reservoir and lake levels are susceptible to interference from inter-basin water transfer projects that are intended to alleviate increasing serious water resource crises. However, the impact of these transfers on riparian buffers as well as to water security is not clear. This paper considers the world’s largest inter-basin water transfer, the South-to-North Water Diversion (SNWD), as an example for assessing changes in riparian buffer width and biomass in order to indicate the influence of the project on the ecological system of the receiving reservoir. The riparian buffer width is determined by Landsat NDWI. Basing on in situ survey, the method that combing unmanned aircraft vehicle (UAV) and remote sensing (Landsat) was employed to calculate riparian biomass. Resultsshow that water arriving from the SNWD directly decrease the existing buffer width due to the rising water level, and riparian biomass shows a negative response to elevated water levels. Therefore, the transferred water will impair the ecological functions of that buffer and increase risk to the security of the water resource. The vegetation cover in extant riparian buffer zones should be restored if the buffers are to be effective as usual. This study provides information useful to assess riparian impact from artificial inter-basin water projects prior to implementation.

Watershed prioritization in the upper Han River basin for soil and water conservation in the South-to-North Water Transfer Project (middle route) of China.

Watershed prioritization with the objective of identifying critical areas to undertake soil and water conservation measures was conducted in the upper Han River basin, the water source area of approximately 95,000km2 for the middle route of China's South-to-North Water Transfer Project. Based on the estimated soil erosion intensity in uplands and clustering analysis of measured nutrient concentrations in rivers, the basin was grouped into very-high-, high-, moderate-, and low-priority regions for water and soil conservation, respectively. The results indicated that soil erosion was primarily controlled by topography, and nutrients in rivers were associated with land use and land cover in uplands. Also, there was large spatial disparity between soil erosion intensity in the uplands and nutrient concentrations in the rivers across the basin. Analysis was then performed to prioritize the basin by the integration of the soil erosion intensity and water quality on a GIS platform in order to identify critical areas for water and soil conservation in the basin. The identified high-priority regions which occupy 5.74% of the drainage areas need immediate attention for soil and water conservation treatments, of which 5.28% is critical for soil erosion prevention and 0.46% for water conservation. Understandings of the basin environment and pollutant loading with spatial explicit are critical to the soil and water resource conservation for the interbasin water transfer project.