Managing Water Resources to Adapt to Climate Change: Facing Uncertainty and Scarcity in a Changing Context

Some of the most significant future efforts in water resources management will be devoted to climate change adaptation. Climate change adaptation is of special concern in regions facing water scarcity where water management is already challenged by many problems. This paper is a review of current knowledge on approaches to address water issues under uncertainty in water-scarce regions, identifying specific policy actions for climate change adaptation. The focus is on regions, like the Mediterranean, California or Australia, where water resources are well developed and have become an essential part of socioeconomic activities but are currently facing significant challenges due to their dependence on water availability to maintain living standards. We provide an overview of the expected impacts of climate change on water resources and discuss management responses based on peer-reviewed studies published over the past three decades. The adaptation choices cover a wide range of options, from adaptive demand management to utilization of remaining marginal water sources. The intensification of successful measures already applied in the past is still viewed as a solution to reduce climate impacts. However, the emphasis is progressively being placed on sustainability, developing and extending the water management paradigm to include not only technical and economic criteria, but also ecological and social considerations.     

Managing Water as a Critical Component of a Changing World

It once seemed that all water managers had to do was to develop and manage infrastructure necessary to convert the natural spatial and temporal distributions of water and its quality to that desired by we humans at acceptable levels of reliability and cost. We are increasingly learning there are limits to achieving such goals, and the consequences can impact just about every component in our economy and society. We’re having to conserve, treat, reuse, find alternatives for and generally get smarter about how we develop and manage our natural resources. Furthermore, we must do it in a political environment of conflicting stakeholder expectations and in ways that minimize the damage to our natural environment as well. No one wants their behavior or life style to contribute to an environment of climatic extremes and regional conflicts that are outside the ranges we and our ecosystems can thrive, or even survive. If we who are in the business of developing and applying models for identifying and evaluating ways of improving how we plan, design, and operate water resources infrastructure systems do not address these broader global environmental and social issues, even partially, and in ways that lead to beneficial impacts, and reduced risks to health and economic security risks, what’s our value? Our literature, including this journal, is full of novel and often useful modeling approaches for identifying and evaluating alternative environmental resource systems designs, plans and policies. Is this enough? This paper addresses ways we might, and in my opinion should, as a discipline, extend our planning and management modeling expertise to address a wider range of societal concerns that stem from the impact water has on almost all human activities. How can we better provide and manage water to better serve society? In short how can we water systems analysts, planners and managers better serve humankind as we manage a critical resource everyone and every economy needs?     

Re-Framing Environmental Social Science Research for Sustainable Water Management in a Changing Climate

This paper considers aspects of environmental social science research in the UK and explores an obvious bias towards the development of instruments to manage demand as an adaptation to climate change, and consequently the predominance of interest in the customer from a demand-side perspective. In the case of water, this has resulted in an inappropriate mixing of individualist research methods designed to measure public perceptions of risk and water-based practices, with mass consumption data that cannot be specifically linked to the individual. This mixing has a tendency to reinforce a long-standing blame culture that drives interest in the development of behaviour change initiatives while the relatively unchallenged hydraulic mission to provide safe drinking water and sanitation progresses. With this in mind this paper reviews examples of water use research from California, Australia, and the UK and highlights the more effective routes to understanding water customers and developing behaviour change initiatives that utilise stages of change models and grounded techniques incorporating qualitative and quantitative data from individual sources. A secondary aim is to argue for re-framing the relations between various actors in a changing climate to allow the development of new policy approaches, learning, and openness, from industry, regulators, and customers, based on new theories from the field.     

Assessment of Water Resources Vulnerability and Adaptation to Climate Change

This paper provides an overview of the 'standard' methodology developed for the United States Country Studies Program on the Assessment of Water Resources Vulnerability and Adaptation to Clim ate Change. The methodology is described in more detail in accompanying articles in this issue. A standard methodology was developed for two reasons. First, for countries with little or no experience in hydrologic and water resources modelling, it provided a simple, yet appropriate set of modelling tools that could be quickly learned and applied with a limited data set. Second, it provided a consistent methodology for synthesizing results for regional and global assessments as well as cross-country and cross-regional comparisons.     

Decision Support for Mainstreaming Climate Change Adaptation in Water Resources Management

Climate change adaptation (CCA) has recently emerged as a new fundamental dimension to be considered in the planning and management of water resources. Because of the need to consider the already perceived changes in climate trends, variability and extremes, and their interactions with evolving social and ecological systems, water management is now facing new challenges. The research community is expected to contribute with innovative methods and tools to support to decision- and policy-makers. Decision Support Systems (DSSs), have a relatively long history in the water management sector. They are usually developed upon pre-existing hydrologic simulation models, providing interfaces for facilitated use beyond the limited group of model developers, and specific routines for decision making (e.g. optimization methods). In recent years, the traditional focus of DSS research has shifted away from the software component, towards the process of structuring problems and aiding decisions, thus including in particular robust methods for stakeholders’ participation. The paper analyses the scientific literature, identifies the main open issues, and proposes an innovative operational approach for the implementation of participatory planning and decision-making processes for CCA in the water domain.     

Integrated Water Management Approach for Adaptation to Climate Change in Highly Water Stressed Basins

Water Resources Management - Adaptation aims at increasing the resilience of natural and human systems to current and future impacts of climate change. The main objective of the current research is...     

Sustainability Assessment of Urban Water Distribution Systems

A methodology is presented for determining sustainability indices for pressure and water age in water distribution systems (WDSs). These sustainability indices are based upon performance criteria including reliability, resiliency, and vulnerability. Pressure and water age are determined for a WDS as a function of operation time using the U.S. Environmental Protection Agency EPANET model. The values of pressure and water age are used to determine reliability, resiliency, and vulnerability performance criteria, which are then combined into the nodal sustainability indices for water age and pressure. In addition, the sustainability index (SI) computations are performed for zones to define the SI for water age and SI for pressure. A combined SI calculation is performed to produce an overall sustainability score for the entire zone in the water distribution network. The proposed methodology can be used to monitor the sustainability of existing WDSs and to help define alternative solutions including changes in pump operation and modifications to WDS to increase the sustainability.     

Measuring Progress on Climate Change Adaptation Policy by Dutch Water Boards

The Netherlands is particularly vulnerable for the impacts of climate change on the water system. Regional water authorities, or water boards, are given an important role to design and implement specific adaptation policies and measures to manage these impacts. From the early 2000s onwards water boards are starting to adapt to climate change impacts, yet no systematic assessments exist to assess whether or not progress is being made and what explains similarities and differences across water boards. This paper aims to address these critical questions by analyzing the progress of all Dutch water boards for the period 2005–2016. We systematically collected and analyzed three consecutive water management plans for all 23 water boards in the Netherlands. We use content analysis methods to analyze progress by looking into their vulnerability and three levels of adaptation: recognition, groundwork and adaptation action. The results show that over time the number of reported climate change adaptation initiatives by the water boards is increasing, but most climate change adaptation is still at the recognition or groundwork level. Our findings reveal a diversity of efforts to adapt to climate change among Dutch water boards. We conclude that while (inter)national water and climate change adaptation policies have called for more adaptation action at regional levels, the unequal progress across the Netherlands suggests that existing ‘soft’ policy measures to push for adaptation might not be sufficient to ensure progress on adaptation across all water boards.     

Quantifying the Urban Water Supply Impacts of Climate Change

The difference in timing between water supply and urban water demand necessitates water storage. Existing reservoirs were designed based upon hydrologic data from a given historical period, and, given recent evidence for climatic change, may be insufficient to meet demand under future climate change scenarios. The focus of this study is to present a generally applicable methodology to assess the ability of existing storage to meet urban water demand under present and projected future climatic scenarios, and to determine the effectiveness of storage capacity expansions. Uncertainties in climatic forcing and projected demand scenarios are considered explicitly by the models. The reservoir system in San Diego, California is used as a case study. We find that the climate change scenarios will be more costly to the city than scenarios using historical hydrologic parameters. The magnitude of the expected costs and the optimal investment policy are sensitive to projected population growth and the accuracy to which our model can predict spills.     

Adaptation of Water Resources System to Water Scarcity and Climate Change in the Suburb Area of Megacities

Water Resources Management - The projection of climate change impacts can be very crucial for water resources planning and management. Hashtgerd plain is an immigrant destination due to...     

Selection of Urban Water Supply Systems For Upgrading

ABSTRACT

The Provincial Waterworks Authority of Thailand (PWA) is considering upgrading a number of their water supply schemes to improve the conditions of existing facilities and to maximize the system efficiency with minimum capital expenditures in order to postpone major investments.

The scope of the study was to review all water supply systems managed by PWA to ascertain the need for immediate action, the technical suitability and the cost effectiveness of upgrading and to set priorities among the systems proposed.

After preliminary screening, 39 systems were selected and ranked in accordance with established selection criteria. Specific recommendations were also given for future actions on the selected systems.     

气候变化下水资源适应性对策的定量评估方法

论述了气候变化背景下水资源管理所面临的主要问题和适应性管理的基本内涵,介绍了应对气候变化影响的水资源适应性管理的国内外研究进展,梳理归纳了目前分析评价适应性管理对策的几种不同方法,认为定量分析适应性对策的经济效益至为关键,成本效益分析的步骤主要包括:①点绘实物量基线曲线;②点绘经济量基线曲线;③点绘过去适应性管理变化曲线;④分析气候变化引发的变化;⑤适应性管理获得的效益变化。     

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.     

Sustainable Catchment Managing in a Climate Changing World: New Integrative Modalities for Connecting Policy Makers,Scientists and Other Stakeholders

This paper characterises some of the main issues confronting water-catchment managing in a climate-changing world and addresses wide-spread concerns about the lack of connectivity between science, policy making and implementation. The paper’s arguments are ‘framed’ within a paradigm of systemic and adaptive governing, regulating, planning and managing understood as a nested systemic hierarchy. It is argued that climate change adaptation is best understood as a coevolutionary dynamic, principally, but not exclusively between human beings and the biophysical world. Two forms of ‘knowledge brokerage’ based on mode 1 (knowledge) and mode 2 (knowing) are distinguished with practical implications. Drawing on extensive research by the authors, eight modalities for enacting ‘knowledge brokerage’ are introduced. The conditions for or against success in employing these modalities are described. Consistent with the views of the Intergovernmental Panel on Climate Change 4th Report 2007, it is argued that water managing is a paradigmatic domain for making climate change adaptation ‘real’ and a systemic issue of global concern at the core of sustainable development.     

Review on Regional Water Resources Assessment Models under Stationary and Changing Climate

A comprehensive assessment of the water resources available in a region or a river basin is essential for finding sustainable solutions for water-related problems concerning both the quantity and quality of the water resources. Research on the development and application of water balance models at different spatial and temporal scales has been carried out since later part of the 19th century. As a result, a great deal of experience on various models and methods has been gained. This paper reviews both traditional long-term water balance methods and the new generation distributed models for assessing available water resources under stationary and changing climatic conditions at different spatial and temporal scales. The applicability and limitations of the methods are addressed. Finally, current advances and challenges in regional- and large-scale assessment of water resources are presented.     

System Dynamics Evaluation of Climate Change Adaptation Strategies for Water Resources Management in Central Iran

The Zayandeh-Rud River basin, Iran, is projected to face spatiotemporally heterogeneous temperature increase and precipitation reduction that will decrease water supply by mid-century. With projected increase (0.70–1.03 °C) in spring temperature and reduction (6–55%) in winter precipitation, the upper Zayandeh-Rud sub-basin, the main source of renewable water supply, will likely become warmer and drier. In the lower sub-basin, 1.1–1.5 °C increase in temperature and 11–31% decrease in annual precipitation are likely. A system dynamics model was used to analyze adaptation strategies taking into account feedbacks between water resources development and biophysical and socioeconomic sub-systems. Results suggest that infrastructural improvements, rigorous water demand management (e.g., replacing high water demand crops such as rice, corn, and alfalfa), and ecosystem-based regulatory prioritization, complemented by supply augmentation can temporarily alleviate water stress in a basin that is essentially governed by the Limits to Growth archetype.     

城市自来水与中水系统综合规划的优化研究

面对我国许多城市用水量不断增加与原水资源短缺的现状 ,提出将中水系统纳入城市供水系统 ,统一规划 ,并提出了一套自来水与中水系统综合规划的优化方法 :根据统计回归原理 ,建立供水系统费用模型 ;按照年成本法 ,建立供水系统综合规划的优化模型。经仿真计算 ,获得了满意的结果。     

Characterisation of the Sensitivity of Water Resources Systems to Climate Change

This paper offers a methodology that enables characterisation of the behaviour of water resources systems under the impact of climate change through assessment of sensitivity patterns in a wide range of hydrologic variations produced by such change. Analysis is based on the application of two indicators that, in turn, draw on the results of a system optimisation model. Under this methodology the potential sensitivity of water resources systems in the cases of different climate projections are visualised, allowing those systems that require special attention in their adaptation to climate change to be identified. The methodology is applied to three basins located in Spain: Guadalquivir, Ebro and the Spanish part of the international basin Duero.     

Implications of Urban Form on Water Distribution Systems Performance

This paper presents the results of an investigation into the relationship between urban form and the performance of a water distribution system. The effect of new development or redevelopment on the performance of an expanded rehabilitation of the well-known Anytown water distribution system is examined to provide an insight into their interaction, which can be considered along with other aspects of renewal to achieve more sustainable urban areas. A range of urban growth rates, urban form and water efficiency strategies are studied in relation to the system’s key performance indicators of total cost, resilience and water quality. The urban forms considered in this work are compact/uniform, monocentric, polycentric and edge developments. These development patterns are representative of common development approaches widely applied in urban planning. They also correspond to future settlement patterns, based on adopting four future (socio-economic) scenarios so called Policy Reform (PR), Fortress World (FW), New Sustainability Paradigm (NSP), and Market Forces (MF) respectively. Three growth rates and two water demand efficiency levels are considered. It is concluded the rate and type of urban development has major implications for the redesign and operation of existing water infrastructure in terms of total cost, water quality and system resilience, with uniform expansion (PR) resulting in the most cost-effective system upgrade by a considerable margin. Polycentric expansion as a representative urban form for New Sustainability Paradigm is the least cost-effective if it relies on centralised water distribution system to provide service to customers. Edge expansion (MF) has both the cheapest and the most expensive expansion costs depending on location of the expansion. Monocentric urban development (FW) does not result in the most cost-effective system contrary to what has been reported in the literature. Water efficiency measures had relatively little impact on overall performance as it was balanced out with demand increase due to new growth.     

Water Management in Integrated Service Systems: Accounting for Water Flows in Urban Areas

This article focuses on studying the natural and artificial water flows of the service sector from an industrial ecology perspective. The purpose is to determine, in the area under study, the water consumption of the service sector and the most water demanding services in global and relative terms, total water consumption per year and liters per user per year (Lpu) respectively, as well as the existing and potential water flow interrelations among service facilities to reduce their water consumption. Finally we propose measures for water consumption minimization, recycling and reusability based on the results of the diagnosis. The analyzed system is Montjuïc Urban Park (Barcelona, Spain), where the economic activity is based on the service sector (about 200 service facilities and no industrial activities). In the individual study of services we found an average consumption of 75 Lpu, with a large range in the water consumption by service types (between 17 and 156 Lpu), and between facilities of the same service type (51 and 155 Lpu). These results indicate a high level and low regulation of water consumption among the service facilities. In the study of the interrelations between the services we found that a high potential for hydrological saving exists in the system (equivalent to 50% of the potable water inflow from the supply network). The results indicate a lack of ecosystemic and synergic vision in the service sector. Interrelations among water flows have to be established, by means of rainwater collection and the reuse of water flows from swimming pools and ornamental fountains. The article proposes the application of industrial ecology methods to improve water management inside Montjuïc Urban Park and, in general, within any system where the service sector is the main economic activity.