Showing papers on "Water supply published in 2015"
TL;DR: This paper found that precipitation deficits in California were more than twice as likely to yield drought years if they occurred when conditions were warm and that anthropogenic warming is increasing the probability of co-occurring warm-dry conditions like those that have created the acute human and ecosystem impacts associated with the 2012-2014 drought in California.
Abstract: California is currently in the midst of a record-setting drought. The drought began in 2012 and now includes the lowest calendar-year and 12-mo precipitation, the highest annual temperature, and the most extreme drought indicators on record. The extremely warm and dry conditions have led to acute water shortages, groundwater overdraft, critically low streamflow, and enhanced wildfire risk. Analyzing historical climate observations from California, we find that precipitation deficits in California were more than twice as likely to yield drought years if they occurred when conditions were warm. We find that although there has not been a substantial change in the probability of either negative or moderately negative precipitation anomalies in recent decades, the occurrence of drought years has been greater in the past two decades than in the preceding century. In addition, the probability that precipitation deficits co-occur with warm conditions and the probability that precipitation deficits produce drought have both increased. Climate model experiments with and without anthropogenic forcings reveal that human activities have increased the probability that dry precipitation years are also warm. Further, a large ensemble of climate model realizations reveals that additional global warming over the next few decades is very likely to create ∼100% probability that any annual-scale dry period is also extremely warm. We therefore conclude that anthropogenic warming is increasing the probability of co-occurring warm–dry conditions like those that have created the acute human and ecosystem impacts associated with the “exceptional” 2012–2014 drought in California.
980 citations
TL;DR: This study compiles a full inventory for physical water transfers at a provincial level and maps virtual water flows between Chinese provinces in 2007 and 2030 and concludes that much greater attention needs to be paid to water demand management rather than the current focus on supply-oriented management.
Abstract: Water can be redistributed through, in physical terms, water transfer projects and virtually, embodied water for the production of traded products. Here, we explore whether such water redistributions can help mitigate water stress in China. This study, for the first time to our knowledge, both compiles a full inventory for physical water transfers at a provincial level and maps virtual water flows between Chinese provinces in 2007 and 2030. Our results show that, at the national level, physical water flows because of the major water transfer projects amounted to 4.5% of national water supply, whereas virtual water flows accounted for 35% (varies between 11% and 65% at the provincial level) in 2007. Furthermore, our analysis shows that both physical and virtual water flows do not play a major role in mitigating water stress in the water-receiving regions but exacerbate water stress for the water-exporting regions of China. Future water stress in the main water-exporting provinces is likely to increase further based on our analysis of the historical trajectory of the major governing socioeconomic and technical factors and the full implementation of policy initiatives relating to water use and economic development. Improving water use efficiency is key to mitigating water stress, but the efficiency gains will be largely offset by the water demand increase caused by continued economic development. We conclude that much greater attention needs to be paid to water demand management rather than the current focus on supply-oriented management.
383 citations
TL;DR: In this paper, the authors present a comprehensive literature review of solar water pumping technology, evaluate the economic viability, identify research gaps and impediments in the widespread propagation of PV water pumping systems and technology.
Abstract: The deficit in electricity and high diesel costs affects the pumping requirements of community water supplies and irrigation; so using solar energy for water pumping is a promising alternative to conventional electricity and diesel based pumping systems. Solar water pumping is based on photovoltaic (PV) technology that converts solar energy into electrical energy to run a DC or AC motor based water pump. The main objective of the study is to present a comprehensive literature review of solar pumping technology, evaluate the economic viability, identify research gaps and impediments in the widespread propagation of solar water pumping systems and technology. The study focuses on update on solar water pumping technology, performance analysis, optimum sizing, degradation of PV generator supplying power to pump, economic and environmental aspects and advances in PV materials and efficiency improvements. An update on the current state of research and utilization of solar water pumping technology is presented. Factors affecting performance of PV water pumping system, degradation of PV modules and efficiency improving techniques of PV water pumping systems are identified. Solar water pumping is found to be economically viable in comparison to electricity or diesel based systems for irrigation and water supplies in rural, urban and remote regions. The investment payback for some PV water pumping systems is found to be 4–6 years. The recent Indian incentives for PV pumping and policy initiatives for the promotion of solar water pumping in developing countries are also discussed. Potential follow-up research areas are also identified.
383 citations
TL;DR: In this paper, the authors provide a systematic approach for integrating soil hydrology and plant physiology into the context of crop production, and derive management measures for cropping systems under specific drought conditions.
Abstract: Drought is a predominant cause of low yields worldwide. There is an urgent need for more water efficient cropping systems facing large water consumption of irrigated agriculture and high unproductive losses via runoff and evaporation. Identification of yield-limiting constraints in the plant–soil–atmosphere continuum are the key to improved management of plant water stress. Crop ecology provides a systematic approach for this purpose integrating soil hydrology and plant physiology into the context of crop production. We review main climate, soil and plant properties and processes that determine yield in different water-limited environments. From this analysis, management measures for cropping systems under specific drought conditions are derived. Major findings from literature analysis are as follows. (1) Unproductive water losses such as evaporation and runoff increase from continental in-season rainfall climates to storage-dependent winter rainfall climates. Highest losses occur under tropical residual moisture regimes with short intense rainy season. (2) Sites with a climatic dry season require adaptation via phenology and water saving to ensure stable yields. Intermittent droughts can be buffered via the root system, which is still largely underutilised for better stress resistance. (3) At short-term better management options such as mulching and date of seeding allow to adjust cropping systems to site constraints. Adapted cultivars can improve the synchronisation between crop water demand and soil supply. At long term, soil hydraulic and plant physiological constraints can be overcome by changing tillage systems and breeding new varieties with higher stress resistance. (4) Interactions between plant and soil, particularly in the rhizosphere, are a way towards better crop water supply. Targeted management of such plant–soil interactions is still at infancy. We conclude that understanding site-specific stress hydrology is imperative to select the most efficient measures to mitigate stress. Major progress in future can be expected from crop ecology focussing on the management of complex plant (root)–soil interactions.
358 citations
TL;DR: The Chemical Water and Wastewater Treatment Series provides authoritative coverage of the key current developments in the chemical treatment of water and wastewater in theory or practice and related problems such as sludge production and properties, and the reuse of chemicals and chemically-treated waters and sludges.
Abstract: In the wake of the Millennium Declaration and the Johannesburg resolutions, many countries have begun to address or re-write their policies regarding water supply and wastewater disposal. The goal is to provide high-quality drinking-water for more people and to safely dispose of spent waters from a large portion of the population than today.
This book, as its predecessors, provides information and technical solutions to accomplish this mammoth task. It is the outcome of collective experience and know-how exchanged between experts in the field of water technology from all over the world: from the Americas, from central and southern Africa, from Europe and from different parts of Asia.
The Chemical Water and Wastewater Treatment Series provides authoritative coverage of the key current developments in the chemical treatment of water and wastewater in theory or practice and related problems such as sludge production and properties, and the reuse of chemicals and chemically-treated waters and sludges.
Chemical Water and Wastewater Treatment VIII is a valuable resource for managers, scientists, plant operators and others interested in chemical water and wastewater treatment technology.
This title belongs to Chemical Water & Wastewater Treatment Series
ISBN: 9781843391456 (Print)
ISBN: 9781780402840 (eBook)
337 citations
TL;DR: The human health risk assessment performed showed that appreciable risks to the consumer's health arising from exposure to trace levels of pharmaceuticals in drinking water are extremely unlikely, as RQs values were all below 0.001.
289 citations
TL;DR: In this article, the authors present the energy and water needs for water supply, wastewater treatment, and power generation systems and critically examine the potential opportunities for achieving energy or water autarky in these systems.
Abstract: The energy-water nexus of the water supply, wastewater treatment and power generation systems has been well discussed. It is very clear that one source cannot be produced or supplied without involving the other source. Since the two systems are intertwined with mutual needs, it is difficult to resolve the issues associated with them in isolation. However, combined solutions through integrated approaches may not be feasible in all situations. Therefore, it is important to consider the energy or water autarky (self-sufficiency) of these systems. If these systems can achieve autarky for the energy and water needs independently, such configurations can be considered sustainable. This review paper presents the energy and water needs for water supply, wastewater treatment, and power generation systems and critically examines the potential opportunities for achieving energy and water autarky in these systems. A detailed view of the water supply and wastewater treatment systems’ energy footprint was presented and similarly the water footprint of various power plants. Different approaches for achieving energy autarky in the wastewater treatment systems as well as approaches for water autarky in the power generation systems were discussed. It is imperative that future developments should consider an integrated design approach to improve the overall system autarky by communicating between the two individual systems, by considering synergistic energy-water production, by collaborating resources planning and energy-water infrastructure synergies supported by science and system-based natural resource policies and regulations.
247 citations
TL;DR: This manuscript is the first comprehensive review of the literature in this quickly evolving water research domain and contributes a general framework for the classification of residential water demand modeling studies, which allows revising consolidated approaches, describing emerging trends, and identifying potential future developments.
Abstract: Over the last two decades, water smart metering programs have been launched in a number of medium to large cities worldwide to nearly continuously monitor water consumption at the single household level. The availability of data at such very high spatial and temporal resolution advanced the ability in characterizing, modeling, and, ultimately, designing user-oriented residential water demand management strategies. Research to date has been focusing on one or more of these aspects but with limited integration between the specialized methodologies developed so far. This manuscript is the first comprehensive review of the literature in this quickly evolving water research domain. The paper contributes a general framework for the classification of residential water demand modeling studies, which allows revising consolidated approaches, describing emerging trends, and identifying potential future developments. In particular, the future challenges posed by growing population demands, constrained sources of water supply and climate change impacts are expected to require more and more integrated procedures for effectively supporting residential water demand modeling and management in several countries across the world. We review high resolution residential water demand modeling studies.We provide a classification of existing technologies and methodologies.We identify current trends, challenges and opportunities for future development.
205 citations
Spanish National Research Council1, Catalan Institute for Water Research2, University of Trento3, University of Padua4, Claude Bernard University Lyon 15, University of the Basque Country6, University of Tübingen7, Swedish Meteorological and Hydrological Institute8, Wageningen University and Research Centre9, Athens University of Economics and Business10, London School of Economics and Political Science11, Ludwig Maximilian University of Munich12, Helmholtz Centre for Environmental Research - UFZ13, Jožef Stefan Institute14, University of Barcelona15, Institut national de la recherche scientifique16, University of Belgrade17, Catalan Institution for Research and Advanced Studies18, University of Girona19, Netherlands Organisation for Applied Scientific Research20, Imperial College London21
TL;DR: The EU-FP7 project GLOBAQUA studies six river basins affected by water scarcity, and aims to answer the following questions: how does water scarcity interact with other existing stressors in the study river Basins?
180 citations
TL;DR: International, multidisciplinary cooperation and collaboration will be needed to promote global water security and to protect human health, particularly in low-income countries that do not have the resources necessary to adapt on their own.
Abstract: Background Climate change is expected to bring increases in average global temperatures (1.4°C–5.8°C [34.52°F–42.44°F] by 2100) and precipitation levels to varying degrees around the globe. The availability and quality of water will be severely affected, and public health threats from the lack of this valuable resource will be great unless water-scarce nations are able to adapt. Saudi Arabia provides a good example of how the climate and unsustainable human activity go hand in hand in creating stress on and depleting water resources, and an example for adaptation and mitigation. Method A search of the English literature addressing climate change, water scarcity, human health, and related topics was conducted using online resources and databases accessed through the University at Albany, State University of New York library web page. Results Water scarcity, which encompasses both water availability and water quality, is an important indicator of health. Beyond drinking, water supply is intimately linked to food security, sanitation, and hygiene, which are primary contributors to the global burden of disease. Poor and disadvantaged populations are the ones who will suffer most from the negative effects of climate change on water supply and associated human health issues. Examples of adaptation and mitigation measures that can help reduce the strain on conventional water resources (surface waters and fossil aquifers or groundwater) include desalination, wastewater recycling and reuse, and outsourcing food items or “virtual water trade.” These are strategies being used by Saudi Arabia, a country that is water poor primarily due to decades of irresponsible irrigation practices. The human and environmental health risks associated with these adaptation measures are examined. Finally, strategies to protect human health through international collaboration and the importance of these efforts are discussed. Conclusion International, multidisciplinary cooperation and collaboration will be needed to promote global water security and to protect human health, particularly in low-income countries that do not have the resources necessary to adapt on their own.
176 citations
TL;DR: In this paper, the authors divide water resource management into two interdependent elements, related firstly to water demand and secondly to water supply and allocation, and discuss the pros and cons of available algorithms, address various sources of uncertainty and highlight limitations in current applications.
Abstract: Human activities have caused various changes to the Earth system, and hence the interconnections between human activities and the Earth system should be recognized and reflected in models that simulate Earth system processes. One key anthropogenic activity is water resource management, which determines the dynamics of human–water interactions in time and space and controls human livelihoods and economy, including energy and food production. There are immediate needs to include water resource management in Earth system models. First, the extent of human water requirements is increasing rapidly at the global scale and it is crucial to analyze the possible imbalance between water demands and supply under various scenarios of climate change and across various temporal and spatial scales. Second, recent observations show that human–water interactions, manifested through water resource management, can substantially alter the terrestrial water cycle, affect land–atmospheric feedbacks and may further interact with climate and contribute to sea-level change. Due to the importance of water resource management in determining the future of the global water and climate cycles, the World Climate Research Program's Global Energy and Water Exchanges project (WRCP-GEWEX) has recently identified gaps in describing human–water interactions as one of the grand challenges in Earth system modeling (GEWEX, 2012). Here, we divide water resource management into two interdependent elements, related firstly to water demand and secondly to water supply and allocation. In this paper, we survey the current literature on how various components of water demand have been included in large-scale models, in particular land surface and global hydrological models. Issues of water supply and allocation are addressed in a companion paper. The available algorithms to represent the dominant demands are classified based on the demand type, mode of simulation and underlying modeling assumptions. We discuss the pros and cons of available algorithms, address various sources of uncertainty and highlight limitations in current applications. We conclude that current capability of large-scale models to represent human water demands is rather limited, particularly with respect to future projections and coupled land–atmospheric simulations. To fill these gaps, the available models, algorithms and data for representing various water demands should be systematically tested, intercompared and improved. In particular, human water demands should be considered in conjunction with water supply and allocation, particularly in the face of water scarcity and unknown future climate.
TL;DR: In this paper, a rapid in-home survey and water testing was conducted 2 weeks following the spill to understand resident perceptions, tap water chemical levels, and premise plumbing flushing effectiveness.
Abstract: During January 2014, an industrial solvent contaminated West Virginia’s Elk River and 15% of the state population’s tap water. A rapid in-home survey and water testing was conducted 2 weeks following the spill to understand resident perceptions, tap water chemical levels, and premise plumbing flushing effectiveness. Water odors were detected in all 10 homes sampled before and after premise plumbing flushing. Survey and medical data indicated flushing caused adverse health impacts. Bench-scale experiments and physiochemical property predictions showed flushing promoted chemical volatilization, and contaminants did not appreciably sorb into cross-linked polyethylene (PEX) pipe. Flushing reduced tap water 4-methylcyclohexanemethanol (4-MCHM) concentrations within some but not all homes. 4-MCHM was detected at unflushed (<10 to 420 μg/L) and flushed plumbing systems (<10 to 96 μg/L) and sometimes concentrations differed among faucets within each home. All waters contained less 4-MCHM than the 1000 μg/L Centers for Disease Control drinking water limit, but one home exceeded the 120 μg/L drinking water limit established by independent toxicologists. Nearly all households refused to resume water use activities after flushing because of water safety concerns. Science based flushing protocols should be developed to expedite recovery, minimize health impacts, and reduce concentrations in homes when future events occur.
TL;DR: The results clearly show that in the United States, over the course of the 21st century and under one set of consistent socioeconomics, the reductions in water stress from slower rates of climate change resulting from emission mitigation are overwhelmed by the increased waterstress from the emissions mitigation itself.
Abstract: There is evidence that warming leads to greater evapotranspiration and surface drying, thus contributing to increasing intensity and duration of drought and implying that mitigation would reduce water stresses. However, understanding the overall impact of climate change mitigation on water resources requires accounting for the second part of the equation, i.e., the impact of mitigation-induced changes in water demands from human activities. By using integrated, high-resolution models of human and natural system processes to understand potential synergies and/or constraints within the climate–energy–water nexus, we show that in the United States, over the course of the 21st century and under one set of consistent socioeconomics, the reductions in water stress from slower rates of climate change resulting from emission mitigation are overwhelmed by the increased water stress from the emissions mitigation itself. The finding that the human dimension outpaces the benefits from mitigating climate change is contradictory to the general perception that climate change mitigation improves water conditions. This research shows the potential for unintended and negative consequences of climate change mitigation.
Book•
01 Jan 2015
TL;DR: The Global Dialogue for Water Security and Economic Growth as mentioned in this paper is a joint initiative of the Global Water Partnership (GWP) and the OECD to promote and accelerate a transition to water security, by connecting policymakers and practitioners through global and country level consultations and through an expert task force analysis of the links between water security and sustainable economic growth.
Abstract: The Global Dialogue for Water Security and Economic Growth is a joint initiative of the GWP and the OECD to promote and accelerate a transition to water security, by connecting policymakers and practitioners through global and country level consultations and through an expert task force analysis of the links between water security and sustainable economic growth. About GWP The mission of the Global Water Partnership (GWP) is to advance governance and management of water resources for sustainable and equitable development. GWP is an intergovernmental organisation and a global network of 13 Regional Water Partnerships, 85 Country Water Partnerships and more than 3,000 Partner organisations in 172 countries. The GWP network is committed to building a water secure world. About OECD The mission of the Organisation for Economic Cooperation and Development (OECD) is to promote policies that will improve the economic and social well-being of people around the world. The OECD provides a forum in which governments can work together to share experiences and seek solutions to common problems. We work with governments to understand what drives economic, social and environmental change. OECD work on water focuses on water economics and governance. It aims at facilitating the reform of water policies, so that they are better attuned to current and future challenges. The views expressed in this report do not necessarily represent the official views of the GWP, nor of the OECD and the governments of its constituent countries. Acknowledgements 8 Executive Summary 12 Chapter 1: Introduction 32 Chapter 2: Water security, sustainable growth, and well-being 36 2.1 The water security challenge 38 Framing the water security challenge 39 The importance of water endowments 41 2.2 The complex economics of water 44 The economic dynamics of water-related investments 44 Appraising investments in water security 46 Finding the right water security investments 47 2.3 A theoretical model of the dynamics of water-related risk, investment, and growth 50 2.4 An empirical analysis of the impact of hydrological variability on growth 54 The impact of hydro-climatic variability on economic growth 54 Two characteristics that influence vulnerability to water-related risks 62 2.5 Summary 64 Chapter 3: The global status of water security 68 3.1 Four headline risks 71 3.2 Risk-based indicators of water security 72 3.3 Global analysis of water security: (1) water scarcity 74 Likelihood of water scarcity 74 Consequence of surface and groundwater water scarcity 79 Projecting future agricultural risks and opportunities 83 …
TL;DR: Assessment of future changes in flow and water quality utilising a modelling approach as a means of assessment in a very complex system indicates a significant increase in monsoon flows under the future climates, with enhanced flood potential.
Abstract: The potential impacts of climate change and socio-economic change on flow and water quality in rivers worldwide is a key area of interest. The Ganges–Brahmaputra–Meghna (GBM) is one of the largest river basins in the world serving a population of over 650 million, and is of vital concern to India and Bangladesh as it provides fresh water for people, agriculture, industry, conservation and for the delta system downstream. This paper seeks to assess future changes in flow and water quality utilising a modelling approach as a means of assessment in a very complex system. The INCA-N model has been applied to the Ganges, Brahmaputra and Meghna river systems to simulate flow and water quality along the rivers under a range of future climate conditions. Three model realisations of the Met Office Hadley Centre global and regional climate models were selected from 17 perturbed model runs to evaluate a range of potential futures in climate. In addition, the models have also been evaluated using socio-economic scenarios, comprising (1) a business as usual future, (2) a more sustainable future, and (3) a less sustainable future. Model results for the 2050s and the 2090s indicate a significant increase in monsoon flows under the future climates, with enhanced flood potential. Low flows are predicted to fall with extended drought periods, which could have impacts on water and sediment supply, irrigated agriculture and saline intrusion. In contrast, the socio-economic changes had relatively little impact on flows, except under the low flow regimes where increased irrigation could further reduce water availability. However, should large scale water transfers upstream of Bangladesh be constructed, these have the potential to reduce flows and divert water away from the delta region depending on the volume and timing of the transfers. This could have significant implications for the delta in terms of saline intrusion, water supply, agriculture and maintaining crucial ecosystems such as the mangrove forests, with serious implications for people's livelihoods in the area. The socio-economic scenarios have a significant impact on water quality, altering nutrient fluxes being transported into the delta region.
TL;DR: In this paper, the authors present a system dynamics model that augments the usual water utility representation of the physical linkages of water grids, by adding interconnected feedback loops in tariff structures, demand levels and financing capacity.
TL;DR: The time is right for a global initiative to develop integrated models based on multiple hypotheses for data support, water resource management algorithms and host models in a unified uncertainty assessment framework, and a key to this development is the availability of regional-scale data for model development, diagnosis and validation.
Abstract: . Human water use has significantly increased during the recent past. Water withdrawals from surface and groundwater sources have altered terrestrial discharge and storage, with large variability in time and space. These withdrawals are driven by sectoral demands for water, but are commonly subject to supply constraints, which determine water allocation. Water supply and allocation, therefore, should be considered together with water demand and appropriately included in Earth system models to address various large-scale effects with or without considering possible climate interactions. In a companion paper, we review the modeling of demand in large-scale models. Here, we review the algorithms developed to represent the elements of water supply and allocation in land surface and global hydrologic models. We note that some potentially important online implications, such as the effects of large reservoirs on land–atmospheric feedbacks, have not yet been fully investigated. Regarding offline implications, we find that there are important elements, such as groundwater availability and withdrawals, and the representation of large reservoirs, which should be improved. We identify major sources of uncertainty in current simulations due to limitations in data support, water allocation algorithms, host large-scale models as well as propagation of various biases across the integrated modeling system. Considering these findings with those highlighted in our companion paper, we note that advancements in computation and coupling techniques as well as improvements in natural and anthropogenic process representation and parameterization in host large-scale models, in conjunction with remote sensing and data assimilation can facilitate inclusion of water resource management at larger scales. Nonetheless, various modeling options should be carefully considered, diagnosed and intercompared. We propose a modular framework to develop integrated models based on multiple hypotheses for data support, water resource management algorithms and host models in a unified uncertainty assessment framework. A key to this development is the availability of regional-scale data for model development, diagnosis and validation. We argue that the time is right for a global initiative, based on regional case studies, to move this agenda forward.
TL;DR: This manuscript is intended to provide a critical review of recent publications that address the future water requirements of electricity production and define the factors that will moderate theWater requirements of the electric grid moving forward to inform future research.
Abstract: Electricity generation often requires large amounts of water, most notably for cooling thermoelectric power generators and moving hydroelectric turbines. This so-called “electricity-water nexus” has received increasing attention in recent years by governments, nongovernmental organizations, industry, and academics, especially in light of increasing water stress in many regions around the world. Although many analyses have attempted to project the future water requirements of electricity generation, projections vary considerably due to differences in temporal and spatial boundaries, modeling frameworks, and scenario definitions. This manuscript is intended to provide a critical review of recent publications that address the future water requirements of electricity production and define the factors that will moderate the water requirements of the electric grid moving forward to inform future research. The five variables identified include changes in (1) fuel consumption patterns, (2) cooling technology pref...
TL;DR: In this article, the authors quantitatively assess the likelihood of drought impact occurrence as a function of the standardized precipitation evapotranspiration index for four European macro regions using logistic regression.
Abstract: Drought in Europe is a hazard with a wide range of transboundary, environmental and socio-economic impacts on various sectors including agriculture, energy production, public water supply and water quality. Despite the apparent importance of this natural hazard, observed pan-European drought impacts have not yet been quantitatively related to the most important climatological drivers to map drought risk on a continental scale. This contribution approaches the issue by quantitatively assessing the likelihood of drought impact occurrence as a function of the standardized precipitation evapotranspiration index for four European macro regions using logistic regression. The resulting models allow mapping the sector-specific likelihood of drought impact occurrence for specific index levels. For the most severe drought conditions the maps suggest the highest risk of impact occurrence for ?Water Quality? in Maritime Europe, followed by ?Agriculture & Livestock Farming? in Western Mediterranean Europe and ?Energy & Industry? in Maritime Europe. Merely impacts on ?Public Water Supply? result in overall lower risk estimates. The work suggests that modeling and mapping for North- and Southeastern Europe requires further enhancement to the impact database in these regions. Such maps may become an essential component of drought risk management to foster resilience for this hazard at large scale.
TL;DR: In this article, a seasonal calibration scheme was proposed, in which SWAT was calibrated separately for the dry and wet periods and the "optimal" simulation results of these two periods were combined into a complete runoff series.
Journal Article•
TL;DR: P piped water is less likely to be contaminated compared with other water supply types at both the source and in HSW, and a focus on upgrading water services to piped supplies may help improve safety, including for those drinking stored water.
Abstract: BackgroundAccess to safe drinking water is essential for health. Monitoring access to drinking water focuses on water supply type at the source, but there is limited evidence on whether quality dif...
TL;DR: The use of rainwater tanks to supplement water supply can reduce the frequency and volume of urban stormwater run-off that is otherwise conveyed directly to streams via conventional stormwater drainage systems.
Abstract: Urban stormwater run-off degrades the ecological condition of streams. The use of rainwater tanks to supplement water supply can reduce the frequency and volume of urban stormwater run-off that is otherwise conveyed directly to streams via conventional stormwater drainage systems. Few studies, however, have examined the use of tanks in the context of managing flow regimes for stream protection, with most focussed uniquely on their water conservation benefits. We used measured tank water level data to assess the performance of 12 domestic rainwater tanks against the dual criteria of their ability to (i) reduce potable mains water usage and (ii) retain run-off from rainfall events and thus reduce the volume and frequency of stormwater run-off. We found that five households relied almost entirely on tank water. Three of the tanks achieved stormwater retention performance approaching that of the same area of pre-developed land, although nine did not – a consequence of limited demand and small tank capacity. Our results suggest that tank water usage can result in substantial reductions in mains water use, if regular and sufficiently large domestic demands are connected to tanks. In many cases, such demands will also result in the best stormwater retention performance. Our results highlight an opportunity to design tank systems to achieve multiple objectives. Application of similar analyses in different locations will help to optimize tanks for simultaneous water supply and stormwater retention purposes. Copyright © 2014 John Wiley & Sons, Ltd.
Journal Article•
TL;DR: In this paper, the authors study food, energy and water value chains as networks of action situations (NAS) where actors' decisions depend not only on the institutional structure of a particular situation but also on the decisions made in related situations.
Abstract: A number of frameworks have been used to study the water-food-energy nexus; but few of these consider the role of institutions in mediating environmental outcomes. In this paper we aim to start filling that gap by combining insights from the Institutional Analysis and Development (IAD) framework and value chain analysis. Specifically we study food, energy and water value chains as networks of action situations (NAS) where actorsʼdecisions depend not only on the institutional structure of a particular situation but also on the decisions made in related situations. Although the IAD framework has developed a solid reputation in the policy sciences, empirical applications of the related NAS concept are rare. Value-chain analysis can help drawing the empirical boundaries of NAS as embedded in production processes.Inthis paper we first use value-chain analysis to identify important input-output linkages among water, food and energy production processes, and then apply the IAD-NAS approach to better understand the effect of institutions within and across those processes. The resulting combined framework is then applied to four irrigation-related case studies including: the use of energy for water allocation and food production in an irrigation project in Spain; the production and allocation of treated water for food and bioenergy production in Germany; the allocation of water for food production and urban use in Kenya; and the production and allocation of energy for food production in Hyderabad, India. The case analyses reveal the value of the framework by demonstrating the importance of establishing linkages across energy, water and food-related situations and the ways in which institutions limit or facilitate synergies along the value chains.
TL;DR: Analysis shows many-objective evolutionary optimization coupled with state-of-the art visual analytics can help planners discover more diverse water supply system designs and better understand their inherent trade-offs.
TL;DR: The results indicate that the loss of coniferous forest and the increase of transitional woodland-shrub are related to increased water's pH; while the growth in artificial surfaces and pastures leads mainly to the increased of soluble salts and fecal coliform concentration.
TL;DR: Wang et al. as mentioned in this paper identified and evaluated typical risks associated with PPP projects in the Chinese water supply sector, using a literature review, a Delphi survey, and face-to-face interviews to achieve these objectives.
Abstract: During the past decades in China, the traditional state monopoly has experienced difficulties in meeting the huge demand for new infrastructure and improvement in service levels, engendering the growth of different forms and degrees of private sector involvement. Since the 1990s, China has started experimenting with the public-private partnership (PPP) delivery method in the water supply sector. However, many problems stemming from unsuccessful risk management have been encountered in PPP applications that have eventually led to project failure. This paper aims to identify and evaluate typical risks associated with PPP projects in the Chinese water supply sector. A literature review, a Delphi survey, and face-to-face interviews were used to achieve these objectives. Finally, a register of 16 critical risk factors (CRFs) of water PPP projects in China was established. The findings revealed that completion risk, inflation, and price change risk have a higher impact on Chinese water PPP projects, whe...
TL;DR: North China could be self-sufficient in water without the transfer of water from the south, but the necessary steps — among them, improving local pollution monitoring and building better irrigation infrastructure — are inadequately implemented.
Abstract: Better local water management is the way to keep pace with escalating demands, not pumping water across the country, warn Jon Barnett and colleagues.
TL;DR: In this paper, the authors provide an in-depth analysis on economics of desalination with country specific examples and point out challenges for cost-effective desalification in the future.
Abstract: Desalination has proven to be a reliable and efficient water supply option in many countries, especially in times of water scarcity. However, high desalination costs and high prices for desalinated water (twice or three times higher than those from traditional water sources) have been hindering an uptake and the development of desalination in many countries. Applied desalination technology, capital and operational costs, production capacity, water salinity are just a few factors determining the final cost of desalinated water that varies considerably between $1.7–9.5/kgal ($0.45–2.51/m3). The final prices for desalinated water and the related costs for local municipalities are among the most crucial determinants of the overall short- and long-term effectiveness of desalination processes. This paper provides an in-depth analysis on economics of desalination with country specific examples. It depicts a comprehensive picture of cost variability of desalinated water and points out challenges for cost-effective desalination in the future.
TL;DR: This review provides updated information on traditional and alternative indicator microorganisms with merits and demerits in view of their role in managing the waterborne health risks as well as conventional and molecular methods proposed for monitoring of indicator and pathogenic microorganisms in the water environment.
Abstract: Water is critical for life, but many people do not have access to clean and safe drinking water and die because of waterborne diseases. The analysis of drinking water for the presence of indicator microorganisms is key to determining microbiological quality and public health safety. However, drinking water-related illness outbreaks are still occurring worldwide. Moreover, different indicator microorganisms are being used in different countries as a tool for the microbiological examination of drinking water. Therefore, it becomes very important to understand the potentials and limitations of indicator microorganisms before implementing the guidelines and regulations designed by various regulatory agencies. This review provides updated information on traditional and alternative indicator microorganisms with merits and demerits in view of their role in managing the waterborne health risks as well as conventional and molecular methods proposed for monitoring of indicator and pathogenic microorganisms in the water environment. Further, the World Health Organization (WHO) water safety plan is emphasized in order to develop the better approaches designed to meet the requirements of safe drinking water supply for all mankind, which is one of the major challenges of the 21st century.