Improving Performance Criteria in the Water Resource Systems Based on Fuzzy Approach

Water Resources Management - Reliability, resilience, and vulnerability (RRV) have been widely used as the performance criteria of a water supply system in the studies conducted over the last three...     

A Scenario-Based Management of Water Resources and Supply Systems Using a Combined System Dynamics and Compromise Programming Approach

Water Resources Management - Long-term sustainability in water supply systems is a major challenge due to water resources depletion, climate change and population growth. This paper presents a...     

Exploring the Mechanism of Surface and Ground Water through Data-Driven Techniques with Sensitivity Analysis for Water Resources Management

The over extraction of groundwater in central-western and southwestern Taiwan has resulted in serious land subsidence for decades. For making countermeasures in response to land subsidence, this study collects long-term hydrological data to explore the relationships between surface water and groundwater in various monitoring stations, and then constructs one-month-ahead forecast models by using data-driven techniques for the water resources management of the Zhuoshui River basin in Taiwan. The results demonstrate that the constructed models can accurately forecast monthly groundwater levels. The sensitivity analysis is next conducted on the input variables of the constructed models by using the partial derivative method. The analysis results reveal that streamflow is a predominant factor for groundwater level variation, and therefore streamflow management made by the upstream weir of the river would influence groundwater level variations. This study further implements several scenario analyses based on the interactive mechanism between groundwater and surface water in response to future climatic conditions and weir discharge management, respectively. The results of scenario analyses indicate that the groundwater recharge zone spreads along the Zhuoshui River while lateral and vertical recharge sources would cause different quantities and distribution patterns of groundwater recharge. Besides, an increase in weir discharge would improve groundwater recharge quantities with groundwater level variations at 0.12 m and 0.06 m in wet and dry seasons, respectively. As a consequence, the operation of weir discharge would play an import role in sustainable development of water resources management in the study area.     

Valuating the Receiving Waters of Urban Wastewater Systems through a Stakeholder-based Approach

The valuation of ecological services in European aquatic ecosystems is increasingly deemed to be an essential element for the integrated management concept pursued by the Water Framework Directive (2000/60/EC). However, the assessment methods are often doubted for their objectivity and transparency when based on the elicitation of stated preferences. The current research attempted to explicitly focus on the biases linked with the stakeholders participating in assessing methods operating with stated preferences. The most significant stakeholder groups were classified in three broad teams of Experts, Decision Makers and Affected Professions. The three teams' preferences were in turn assessed in economic and non-economic terms for the accentuation of the high fluctuation among the findings, and the threatening biases emerged in the sourcing of stated preference methods. The wastewater treatment plant in Athens, Greece and Saronikos Bay offered a sound case study.     

Water Costs Allocation in Complex Systems Using a Cooperative Game Theory Approach

The management of complex water resource systems that address water service recovery costs and consider adequate contributions and priorities require methods that integrate technical, economic, environmental, social and legal aspects into a comprehensive framework. In Europe, the Water Framework Directive (WFD) 2000/60/EC recommends that the pricing politics in a river basin take into account the cost recovery and the economic sustainability of the water use. However, the current cost allocation methods do not consider the user’s willingness to pay and often do not permit a total cost recovery. Thus, a new approach is required that includes these requirements when defining water rates. This article presents a methodology to allocate water service costs in a water resource system among different users that attempts to fulfil the WFD requirements. The methodology is based on Cooperative Game Theory (CGT) techniques and on the definition of the related characteristic function using a mathematical optimisation approach. The CGT provides the instruments that are necessary to analyse situations that require a cost-sharing rule. The CGT approach can define efficient and fair solutions that provide the appropriate incentives among the parties involved. Therefore, the water system cost allocation has been valued as a game in which it is necessary to determine the right payoff for each player that is, in this case, a water user. To apply the CGT principles in a water resources system, the characteristic function needs to be defined and evaluated using an adequate modelling approach; in this study, it is evaluated using the optimisation model WARGI. (Sechi and Zuddas 2000). The so-called “core” represents the game-solution set. It represents the area of the admissible cost allocation values from which the boundaries on the cost values for each player can be supplied. Within the core lie all of the allocations that satisfy the principles of equity, fairness, justice, efficiency and that guarantee cost recovery. The core of a cooperative game can represent a useful instrument to define the water cost rates. Furthermore, it can be used as a valid support in water resource management to achieve the economic analysis required by the WFD. The methodology was applied to a multi-reservoir and multi-demand water system in Sardinia, Italy.     

基于系统动力学的水资源承载力模拟研究

基于系统动力学建立了区域水资源承载力预测模型,通过区域未来经济社会发展情况,该模型可对区域未来的水资源承载力状况进行模拟预测。以广东省粤北某市为例,结合当地发展目标,利用系统动力学的水资源承载力模型对该市"十三五"期间的水资源承载力状况进行分析预测,并通过敏感性分析得到了对水资源承载力影响较大的因素,最后为该市未来水资源的开发与利用提出了几点建议。     

Towards Adaptation of Water Resource Systems to Climatic and Socio-Economic Change

Climate change is viewed as the major threat to the security of water supplies in most parts of the world in the coming decades, and the water resources literature continues to be dominated by impact and risk assessments based on the latest climate projections from General Circulation Models (GCMs). However, the evidence for anthropogenic changes in precipitation and streamflow records continues to be elusive which, together with the known high uncertainty in GCM ensemble projections, has led to the development of risk assessment methods which are not driven exclusively by GCMs. It is argued that a baseline risk assessment should retain the assumption of climatic stationarity, and be based on the modelling of observed interannual variability as a dominant process in determining water resource system reliability, augmented where justifiable by reliable information from GCMs. However, irrespective of what the climate does in the future, globalization and socio-economic changes are the major drivers for increases in water demand and threats to water security, as exemplified by the burgeoning economies of the BRIC and MINT countries, and the large population increases and economic growth seen in many developing countries. It is suggested that more attention needs to be paid to adaptation to socio-economic change which is arguably more predictable than climatic change, based on what is already known about population and economic growth, lifestyle changes and human choices. More focus is needed on economic analyses that can inform the major investments in water use efficiency measures which can deliver the water savings needed to avert widespread water scarcity. The effectiveness of water use efficiency measures is largely determined by (a) the potential of modern information technology to achieve more efficient water resources management and water use and (b) human responses and choices in the uptake of measures. To assess the potential efficiency gains, it is argued that water resource systems modelling needs to evolve to incorporate the human dimension more explicitly, through Coupled Human and Natural Systems (CHANS) modelling. A CHANS modelling framework is outlined which incorporates agent-based modelling to represent individual choices within the human system, and prospects for assessing the effectiveness of efficiency measures involving individual human responses are discussed.     

Optimal Localization of Pressure Reducing Valves in Water Distribution Systems by a Reformulation Approach

Leakage reduction represents one of the most challenging tasks in managing water distribution systems (WDSs). An effective way to leakage reduction is to carry out network operational pressure management through optimizing locations and regulations for pressure reducing valves (PRVs) and system pressures. This leads to a mixed-integer nonlinear program (MINLP) with a large number of binary variables which make it difficult to solve by an available software package. In this study, instead of directly solving the MINLP problem, we reformulate it to a mathematical program with complementarity constraints which can be efficiently solved by available NLP algorithms. The binary variables are replaced by continuous ones with complementarity constraints to be satisfied by a penalization scheme. To improve the quality of the solution and also to accelerate the convergence, in each relaxed NLP the results of the binary variables are rounded to binary values with which the NLP problem is solved again to achieve a MINLP solution. The final solution will be determined by the best one among the MINLP solutions. The results from two case studies reveal new and better combinations of PRVs as compared with those given in the literature.     

An Efficient Approach for Nodal Water Demand Estimation in Large-scale Water Distribution Systems

Water Resources Management - Real-time modeling of a water distribution system (WDS) is a critical step for the control and operation of such systems. The nodal water demand, as the most important...     

基于循环经济的水资源可持续发展新模式

针对我国水资源短缺及水环境污染的现状,指出了以高效利用水资源和保护水环境为基础的循环经济是实现我国水资源可持续发展的必然选择,并积极探讨了以循环经济为核心理念的水资源可持续发展新模式。通过采取基于循环经济各种切实可行的有利措施和先进技术,可以实现水资源可持续发展,从而有效地解决水环境污染及水资源供需矛盾等问题。     

Optimization Approach to Designing Water Supply Systems in Non-Coastal Areas Suffering from Water Scarcity

This article presents a novel optimization approach to designing water supply systems in non-coastal areas with water scarcity. In such areas, high water demand caused by population increases and economic development can only be satisfied with seawater supply. Furthermore, most of the non-coastal users are located at long distances and sometimes at altitudes very diverse from the coastline, meaning long pipelines and several pumping stations will be required to effectively supply water. The proposed optimization approach based on a mixed integer nonlinear programming model offers optimal designs of water supply systems from an economic and technical perspective. It determines the location and size of desalination plants and the design of the water transport network including pipelines of specified length and diameter and pumping stations that minimize capital and operational costs of the whole system. A case study in a hyper-arid region of Chile was used to validate the applicability of the proposed model and the results show its aptitude for determining global optimal solutions to real-scale problems.     

Sustainability Analysis for Yellow River Water Resources Using the System Dynamics Approach

The water resource issue is one of the most significant problemsthat the Yellow River basin will face this century, and one which has received much attention by public and government for several years. Water authorities will face great challenges in meeting the in-stream flow requirements and providing more water for growing populations, industry and agriculture. In order toevaluate the sustainability of the water resource system inthe study area, an object-oriented system dynamics approachhas been used to develop a model for the water resourcessystem in the Yellow River basin, which is referred to asthe Water Resources System Dynamics (WRSD) model. It hasbeen developed for simulating a water resource system andcapturing the dynamic character of the main elements affectingwater demand and supply in the study area. For thebusiness-as-usual (BaU) scenario, the water demands in theYellow River basin are estimated 50.9, 56.5, and 59.5billion m³ for 2010, 2020, and 2030. The existing andpotential water supplies from surface water, aquifers andtreated waste-water are estimated, and potential waterdemands for domestic, industrial and agricultural uses areprojected. Various water supply and demand scenarios havethen been explored by changing variables and parameters,and the sustainability index of the water supply system isestimated for different sub-regions over various periods.     

水能资源系统与生态系统互动关系的理论分析

在对水能资源系统与生态系统相互关系分析的基础上,分别从生态系统角度、水能资源系统角度提出了水能资源系统与生态系统互动关系的表现层面。从生态系统角度来看,生态系统对水能资源系统起到要素限定、功能保障、价值引导、生态约束等效应;从水能资源系统来看,水能资源的开发对生态系统起到景观改造、空间阻隔、效应干扰效应。以这些功能和效应为基础,水能资源与生态系统的协调应从要素层面、功能层面、效应层面及价值层面进行,综合协调体系的构建是提高二者协调度的重要保障。     

水能资源系统与生态系统互动关系的理论分析

在对水能资源系统与生态系统相互关系分析的基础上,分别从生态系统角度、水能资源系统角度提出了水能资源系统与生态系统互动关系的表现层面。从生态系统角度来看,生态系统对水能资源系统起到要素限定、功能保障、价值引导、生态约束等效应;从水能资源系统来看,水能资源的开发对生态系统起到景观改造、空间阻隔、效应干扰效应。以这些功能和效应为基础,水能资源与生态系统的协调应从要素层面、功能层面、效应层面及价值层面进行,综合协调体系的构建是提高二者协调度的重要保障。     

Modeling Effects of Land use and Vegetation Density on Soil Water Dynamics: Implications on Water Resource Management

Vegetation restoration is helpful in preventing soil erosion but aggravates water scarcity, thus resulting in soil desiccation on the wind–water erosion crisscross region (WWECR) of the Loess Plateau in Northwestern China. However, no guideline currently exists on the selection of plant species and density for restoration purposes. Based on the process model of soil water-carrying capacity for vegetation (SWCCV) originally developed in this region, this study validated the model under a broad range of weather regimes, soil types, and land uses. The SWCCV model was applied as a diagnostic tool to obtain insights into the separate effects of vegetation density and land use on soil water dynamics on the WWECR of the Loess Plateau. Results showed that the total water loss at semi-natural grasslands was close to rainfall while significantly decreasing runoffs, thus indicating that semi-natural grass was suitable for vegetation restoration on the WWECR. If Caragana korshinskii is planted for agronomic and economic benefits, a density of 3,400 trees ha^?1 will yield the most optimal soil water conservation benefits at study site. Our recommended land use and vegetation density were directive and instructional for vegetation restoration on the WWECR and that our modeling approach could be extended to applications in other arid and semi-arid regions.     

Multi-Directional Maximum-Entropy Approach to the Evolutionary Design Optimization of Water Distribution Systems

A new multi-directional search approach that aims at maximizing the flow entropy of water distribution systems is investigated. The aim is to develop an efficient and practical maximum entropy based approach. The resulting optimization problem has four objectives, and the merits of objective reduction in the computational solution of the problem are investigated also. The relationship between statistical flow entropy and hydraulic reliability/failure tolerance is not monotonic. Consequently, a large number of maximum flow entropy solutions must be investigated to strike a balance between cost and hydraulic reliability. A multi-objective evolutionary optimization model is developed that generates simultaneously a wide range of maximum entropy values along with clusters of maximum and near-maximum entropy solutions. Results for a benchmark network and a real network in the literature are included that demonstrate the effectiveness of the procedure.     

Analysis of Water Quantity and Quality Trade-Offs to Inform Selective Harvesting of Inflows in Complex Water Resource Systems

Water Resources Management - Challenges faced by water resource systems are multi-faceted. The problem can be even more pronounced in a dry continent like Australia where the water resources can...     

抓水是个大战略

对晋中市水资源状况及开发利用中存在的问题作了深入的分析研究，提出了解决晋中市水资源问题应着重处理抓大与放小，更新与改造，开发与保护三方面的问题，并结合当前晋中市水利改革实际提出了今后水利发展的目标。     

A Daily Water Balance Modelling Approach for Simulating Performance of Tank-Based Irrigation Systems

Tanks are small reservoirs, which are widely distributed in South India and Sri Lanka, where they represent an important water resource for people, crops, livestock and fish. Considerable efforts have been made to rehabilitate tank irrigation systems in recent decades, but there have been few studies carried out to improve understanding of their hydrology. This paper presents a daily water balance approach, which aims to simulate the dynamic behaviour of tank storage. The model was validated over four seasons for two representative tanks within Mahaweli System H, a major irrigation system in the dry zone of Sri Lanka. Use of the model to evaluate current performance and scope for improvement is demonstrated.