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Showing papers on "Water supply published in 2018"


BookDOI
TL;DR: In this paper, the authors studied water allocation under an irrigation bureaucracy subject to corruption and rent-seeking, and found that the decline in water availability and land values from channel head to tail is accentuated along canals having greater lobbying power at the head than at the tail.
Abstract: Surface irrigation is a common pool resource characterized by asymmetric appropriation opportunities across upstream and downstream water users. Large canal systems are also predominantly managed by the state. This paper studies water allocation under an irrigation bureaucracy subject to corruption and rent-seeking. Data on the landholdings and political influence of nearly quarter million irrigators in Pakistan’s vast Indus Basin watershed allow the construction of a novel index of lobbying power. Consistent with a model of misgovernance, the decline in water availability and land values from channel head to tail is accentuated along canals having greater lobbying power at the head than at the tail.

571 citations


Journal ArticleDOI
01 Jan 2018
TL;DR: In this article, the authors quantify the magnitude of these twin challenges to urban water security, combining a dataset of urban water sources of 482 of the world's largest cities with estimates of future water demand, based on the Intergovernmental Panel on Climate Change (IPCC)s Fifth Assessment scenarios, and predictions of water availability, using the WaterGAP3 modelling framework.
Abstract: Urban water demand will increase by 80% by 2050, while climate change will alter the timing and distribution of water. Here we quantify the magnitude of these twin challenges to urban water security, combining a dataset of urban water sources of 482 of the world’s largest cities with estimates of future water demand, based on the Intergovernmental Panel on Climate Change (IPCC)’s Fifth Assessment scenarios, and predictions of future water availability, using the WaterGAP3 modelling framework. We project an urban surface-water deficit of 1,386–6,764 million m³. More than 27% of cities studied, containing 233 million people, will have water demands that exceed surface-water availability. An additional 19% of cities, which are dependent on surface-water transfers, have a high potential for conflict between the urban and agricultural sectors, since both sectors cannot obtain their estimated future water demands. In 80% of these high-conflict watersheds, improvements in agricultural water-use efficiency could free up enough water for urban use. Investments in improving agricultural water use could thus serve as an important global change adaptation strategy. Rising population and changes in water supply under climate change affect cities globally. This study finds that in 27% of cities studied, water demand is likely to exceed availability by 2050, with many other cities competing with agriculture on water needs.

440 citations


Journal ArticleDOI
01 Apr 2018
TL;DR: In this article, the potential applications of nanomaterials in advancing sustainable water treatment systems and their associated barriers are assessed and future areas of research necessary to realize safe deployment of promising Nanomaterial applications are also identified.
Abstract: Sustainable provision of safe, clean and adequate water supply is a global challenge. Water treatment and desalination technologies remain chemically and energy intensive, ineffective in removing key trace contaminants, and poorly suited to deployment in decentralized (distributed) water treatment systems globally. Several recent efforts have sought to leverage the reactive and tunable properties of nanomaterials to address these technological shortcomings. This Review assesses the potential applications of nanomaterials in advancing sustainable water treatment systems and proposes ways to evaluate the environmental risks and social acceptance of nanotechnology-enabled water treatment processes. Future areas of research necessary to realize safe deployment of promising nanomaterial applications are also identified. Despite recent technological progress, providing safe, clean and sufficient water sustainably for all remains challenging. This Review assesses the potential applications of nanomaterials in advancing the sustainability of water treatment systems, and their associated barriers.

334 citations


Journal ArticleDOI
TL;DR: The current status and future perspectives of advanced membrane processes to meet potable water reuse are highlighted and opportunities and challenges are identified in the context of water reuse.
Abstract: Recycling water from municipal wastewater offers a reliable and sustainable solution to cities and regions facing shortage of water supply. Places including California and Singapore have developed advanced water reuse programs as an integral part of their water management strategy. Membrane technology, particularly reverse osmosis, has been playing a key role in producing high quality recycled water. This feature paper highlights the current status and future perspectives of advanced membrane processes to meet potable water reuse. Recent advances in membrane materials and process configurations are presented and opportunities and challenges are identified in the context of water reuse.

317 citations


Journal ArticleDOI
14 Sep 2018
TL;DR: In this article, the authors take a probabilistic approach to assess global water scarcity projections following feasible combinations of shared socioeconomic pathways and representative concentration pathways for the first half of the twenty-first century and identify changes in the uncertainty range of anticipated water scarcity conditions.
Abstract: Water scarcity, a critical environmental issue worldwide, has primarily been driven by a significant increase in water extractions during the last century In the coming decades, climate and societal changes are projected to further exacerbate water scarcity in many regions worldwide Today, a major issue for the ongoing policy debate is to identify interventions able to address water scarcity challenges in the presence of large uncertainties Here, we take a probabilistic approach to assess global water scarcity projections following feasible combinations of shared socioeconomic pathways and representative concentration pathways for the first half of the twenty-first century We identify—alongside trends in median water scarcity—changes in the uncertainty range of anticipated water scarcity conditions Our results show that median water scarcity and the associated range of uncertainty are generally increasing worldwide, including many major river basins On the basis of these results, we develop a general decision-making framework to enhance policymaking by identifying four representative clusters of specific water policy challenges and needs Designing interventions to address water scarcity under climate change is challenging given the large uncertainties in projected water availability In this study, changes in the uncertainty range of anticipated water scarcity conditions are identified, and a general decision-making framework to support policy decisions is developed

218 citations


Journal ArticleDOI
TL;DR: A review of existing reuse schemes and regulations across the world, found variation, demonstrating the need for assessing benefits and risks on a case-by-case basis as discussed by the authors, and therefore, care must be taken with regulating and monitoring levels of contaminants in the recycled water according to its use.

216 citations


Journal ArticleDOI
TL;DR: It is shown that health-based drinking water quality violations are widespread, with 9–45 million people possibly affected during each of the past 34 years, and hot spots and vulnerability factors associated with violations are identified, which can allow public policies to target underperforming water systems.
Abstract: Ensuring safe water supply for communities across the United States is a growing challenge in the face of aging infrastructure, impaired source water, and strained community finances. In the aftermath of the Flint lead crisis, there is an urgent need to assess the current state of US drinking water. However, no nationwide assessment has yet been conducted on trends in drinking water quality violations across several decades. Efforts to reduce violations are of national concern given that, in 2015, nearly 21 million people relied on community water systems that violated health-based quality standards. In this paper, we evaluate spatial and temporal patterns in health-related violations of the Safe Drinking Water Act using a panel dataset of 17,900 community water systems over the period 1982-2015. We also identify vulnerability factors of communities and water systems through probit regression. Increasing time trends and violation hot spots are detected in several states, particularly in the Southwest region. Repeat violations are prevalent in locations of violation hot spots, indicating that water systems in these regions struggle with recurring issues. In terms of vulnerability factors, we find that violation incidence in rural areas is substantially higher than in urbanized areas. Meanwhile, private ownership and purchased water source are associated with compliance. These findings indicate the types of underperforming systems that might benefit from assistance in achieving consistent compliance. We discuss why certain violations might be clustered in some regions and strategies for improving national drinking water quality.

214 citations


Journal ArticleDOI
TL;DR: A systems approach can be helpful to comprehend the complexity of the urban system, including its relation with its (global) environment, and better understand the dynamics of urban water security.
Abstract: We review the increasing body of research on urban water security. First, we reflect on the four different focusses in water security literature: welfare, equity, sustainability and water-related risks. Second, we make an inventory of the multiple perspectives on urban water security: disciplinary perspectives (e.g. engineering, environmental, public policy, public health), problem-oriented perspectives (e.g. water shortage, flooding, water pollution), goal-oriented perspectives (e.g. better water supply and sanitation, better sewerage and wastewater treatment, safety from flooding, proper urban drainage), integrated-water versus water-integrated perspectives, and policy analytical versus governance perspectives. Third, we take a systems perspective on urban water security, taking the pressure-state-impact-response structure as an analytical framework and link that to the ‘urban water transitions framework’ as proposed by Brown et al (Water. Sci. Technol. 59 2009). A systems approach can be helpful to comprehend the complexity of the urban system, including its relation with its (global) environment, and better understand the dynamics of urban water security. Finally, we reflect on work done in the area of urban water security indices.

204 citations


Journal ArticleDOI
08 Jan 2018-Cities
TL;DR: In this article, the authors investigated the role of green infrastructures (GI) in urban water management in five cities, including Singapore, Berlin, Philadelphia, Melbourne, and Tianjin Eco-city.

169 citations


Journal ArticleDOI
TL;DR: In this article, a holistic methodology and platform to support the resilient and sustainable planning at city region level for multiple sectors was developed for applications in urban energy systems and the energy-water-food nexus, combining agent-based modelling to simulate and forecast resource demands on spatial and temporal scales, with resource network optimization, which incorporates capital expenditures, operational costs, environmental impacts and the opportunity cost of food production foregone.

154 citations


01 Jan 2018
TL;DR: This joint report is the first comprehensive global assessment of WASH in schools and establishes a baseline for the Sustainable Development Goal (SDG) period.
Abstract: Description: The World Health Organization (WHO) and the United Nations Children’s Fund (UNICEF) are responsible for monitoring global progress towards water, sanitation and hygiene (WASH) related Sustainable Development Goal (SDG) targets. The global effort to achieve sanitation and water for all by 2030 is extending beyond the household to include institutional settings, such as schools, healthcare facilities and workplaces. This joint report is the first comprehensive global assessment of WASH in schools and establishes a baseline for the Sustainable Development Goal (SDG) period.

Journal ArticleDOI
TL;DR: This study tracks tap water microbiome assembly in situ, showing that bacterial community composition changes rapidly from the city supply following ~6-day stagnation, along with an increase in cell count along with a developed size-effect model to simulate this process.
Abstract: What happens to tap water when you are away from home? Day-to-day water stagnation in building plumbing can potentially result in water quality deterioration (e.g., lead release or pathogen proliferation), which is a major public health concern. However, little is known about the microbial ecosystem processes in plumbing systems, hindering the development of biological monitoring strategies. Here, we track tap water microbiome assembly in situ, showing that bacterial community composition changes rapidly from the city supply following ~6-day stagnation, along with an increase in cell count from 103 cells/mL to upwards of 7.8 × 105 cells/mL. Remarkably, bacterial community assembly was highly reproducible in this built environment system (median Spearman correlation between temporal replicates = 0.78). Using an island biogeography model, we show that neutral processes arising from the microbial communities in the city water supply (i.e., migration and demographic stochasticity) explained the island community composition in proximal pipes (Goodness-of-fit = 0.48), yet declined as water approached the faucet (Goodness-of-fit = 0.21). We developed a size-effect model to simulate this process, which indicated that pipe diameter drove these changes by mediating the kinetics of hypochlorite decay and cell detachment, affecting selection, migration, and demographic stochasticity. Our study challenges current water quality monitoring practice worldwide which ignore biological growth in plumbing, and suggests the island biogeography model as a useful framework to evaluate building water system quality.

Journal ArticleDOI
TL;DR: The authors measured province-level water resource efficiencies in China from both static and dynamic perspectives, applying the undesirable-output-based Malmquist-Luenberger productivity index to panel data of 30 provinces in China.

Journal ArticleDOI
TL;DR: Evaluation of effluent water quality from published wetland case studies and the expected performance from disinfection processes shows that under appropriate conditions these two unit processes together can likely produce effluent of sufficient quality to meet all nonpotable reuse standards.

Journal ArticleDOI
TL;DR: In addressing arsenic-related health issues, arsenic-exposed population needs to be brought under the coverage of the regular surveillance program for detection and subsequent management of noncommunicable diseases and cancers.
Abstract: Arsenic contamination of groundwater in Bangladesh has been recognized as a major public problem. The arsenic contamination was first identified in the tubewell water in 1993 in a northern district of Bangladesh. Tubewells are the main source of drinking water in rural areas, and except hilly and terrace upland throughout the Bangladesh, the arsenic-contaminated tube-wells are distributed. Fifty million people of Bangladesh were estimated to be at risk of exposure to arsenic through consumption of water from contaminated tubewells. Chronic exposure to arsenic causes arsenicosis and may include multi-organ pathologies. Many of the health effects of chronic toxicity are evident in Bangladesh. Besides dermatological manifestations, noncommunicable diseases including cancer, adverse pregnancy outcomes, and decreased intelligence quotient among the children are reported to be increasing. Cancer due to long-term low-dose arsenic exposure through consumption of contaminated water is now an important concern of Bangladesh as it is being increasingly reported from arsenic-exposed individuals. Stoppage of consumption of the arsenic-contaminated water is the mainstay of arsenicosis prevention and case management. At present, a higher proportion of the people are still consuming arsenic-contaminated water because of the lack of sustainable arsenic-safe water supply. In providing sustainable arsenic-safe water options, any option advocated should be cheap, easy to use, locally maintainable, and owned by the community. In addressing arsenic-related health issues, arsenic-exposed population needs to be brought under the coverage of the regular surveillance program for detection and subsequent management of noncommunicable diseases and cancers.

01 Jan 2018
TL;DR: In this paper, it is argued that addressing water problems at the river basin level is not always sufficient and that many of today's seemingly local water issues carry a (sub)continental or even global dimension, which urges for a governance approach that comprises institutional arrangements at a level beyond that of a river basin.
Abstract: When water problems extend beyond the borders of local communities, the river basin is generally seen as the most appropriate unit for analysis, planning, and institutional arrangements. In this paper it is argued that addressing water problems at the river basin level is not always sufficient. Many of today’s seemingly local water issues carry a (sub)continental or even global dimension, which urges for a governance approach that comprises institutional arrangements at a level beyond that of the river basin. This paper examines a number of arguments for the thesis that good water governance requires a global approach complementary to the river basin approach. Subsequently, it identifies four major issues to be addressed at global scale: Efficiency, equity, sustainability and security of water supply in a globalised world. Finally, the paper raises the question of what kind of institutional arrangements could be developed to cope with the global dimension of water issues. A few possible directions are explored, ranging from an international protocol on full-cost water pricing and a water label for water-intensive products to the implementation of water footprint quotas and the water-neutral concept.

Journal ArticleDOI
TL;DR: The results suggest that physical water resources would mainly satisfy the consumption of urban and environment, and the unbalance between water supply and demand could be filled by virtual water import in water scarce regions.

Journal ArticleDOI
TL;DR: The optimal scenario of PLDL in the Erhai Lake Basin was identified by trade-offs of the four ecosystem services, and the residential participation scenario was identified to be the best choice for PLDL implementation because it achieved the best level of water purification and had the smallest negative effect on other ecosystem services.

Journal ArticleDOI
TL;DR: In this paper, the authors present a review highlighting knowledge gaps in optimisation models related to the water-energy nexus in water supply systems or "water supply side of the nexus".
Abstract: Considering water-energy nexus in optimising water supply systems not only ensures the sustainability of the water supply for increasing water demand but also diminishes water-related energy and environmental concerns. This paper presents a review highlighting knowledge gaps in optimisation models related to the water-energy nexus in water supply systems or “water supply side of the nexus”. Studies reported in the literature are categorised and systematically analysed in terms of different energy sources, centralised/ decentralised approaches and system parameters uncertainties. Several major gaps are identified. These include the lack of optimisation models capturing spatial aspects as well as environmental impacts of the nexus problems. The shortage of models considering uncertainties associated with water demand and renewable energy supply is another knowledge gap in this area. However, the main gap is the absence of models for optimising long-term planning of water supply system considering renewable energy within an urban context. Accordingly, based on this review, we have suggested pointers for future studies in the water supply side of the nexus.


Journal ArticleDOI
TL;DR: In this paper, the authors present reliabilities and economic benefits of RWH systems for six major cities (Dhaka, Chittagong, Rajshahi, Khulna, Sylhet, and Barishal) of the Bangladesh using a daily water balance model.
Abstract: Rainwater harvesting (RWH) has been a popular practice in coastal and arsenic affected rural areas of Bangladesh. However, the urban communities still showing reluctance in adopting a RWH system. The main reason for such reluctance is lack of confidence in potential water savings and payback period on initial investment. To tackle with severe water scarcity in major cities of Bangladesh, the government has made it mandatory to install a RWH system in all the proposed new buildings. This paper presents reliabilities and economic benefits of RWH systems for six major cities (Dhaka, Chittagong, Rajshahi, Khulna, Sylhet, and Barishal) of the Bangladesh using a daily water balance model. Reliability parameters were calculated based on a scenario of six storied residential building with 50 inhabitants and with a roof area of 200 m2. The results indicate that Sylhet and Chittagong regions have the high potentials of rainwater harvesting, where a maximum reliability of 30–40% can be achieved. The results also reveal that approximately 500–800 m3 of water can be saved each year if a rainwater harvesting system is used in combination with the town water supply. This study also proves that the current underground tank sizes in these cities are sufficient to prevent any spillage of water, which may significantly alleviate urban flooding/water logging. Payback period analysis indicate that the costs associated with the installation and maintenance of RWH system could be equalized within 2–6 years depending on the topographic and climatic conditions.

Journal ArticleDOI
TL;DR: The results indicated that the optimal short-term reservoir operation obtained from the non-dominated sorting genetic algorithm II (NSGA-II) could largely increase hydropower output but just slightly affected water supply.

Journal ArticleDOI
TL;DR: In this paper, the authors proposed an approach to measure the scarce water saving associated with virtual water trade (measuring in water withdrawal/use), quantified by multiplying the water use in production with the water stress index (WSI).
Abstract: Trade of commodities can lead to virtual water flows between trading partners. When commodities flow from regions of high water productivity to regions of low water productivity, the trade has the potential to generate water saving. However, this accounting of water saving does not account for the water scarcity status in different regions. It could be that the water saving generated from this trade occurs at the expense of the intensified water scarcity in the exporting region, and exerts limited effect on water stress alleviation in importing regions. In this paper, we propose an approach to measure the scarce water saving associated with virtual water trade (measuring in water withdrawal/use). The scarce water is quantified by multiplying the water use in production with the water stress index (WSI). We assessed the scarce water saving/loss through interprovincial trade within China using a multi-region input-output table from 2010. The results show that interprovincial trade resulted in 14.2 km3 of water loss without considering water stress, but only 0.4 km3 scarce water loss using the scarce water concept. Among the 435 total connections of virtual water flows, 254 connections contributed to 20.2 km3 of scarce water saving. Most of these connections are virtual water flows from provinces with lower WSI to that with higher WSI. Conversely, 175 connections contributed to 20.6 km3 of scarce water loss. The virtual water flow connections between Xinjiang and other provinces stood out as the biggest contributors, accounting for 66% of total scarce water loss. The results show the importance of assessing water savings generated from trade with consideration of both water scarcity status and water productivity across regions. Identifying key connections of scarce water saving is useful in guiding interregional economic restructuring towards water stress alleviation, a major goal of China's sustainable development strategy.

Journal ArticleDOI
TL;DR: This study provides insight into China's water footprint and virtual water trade using three specific water named Green, Blue and Grey and policy implications are proposed for China's long term sustainable water management and for global supply chain management in general.

Journal ArticleDOI
TL;DR: In this article, the authors developed an economic analysis tool, called ERain, to combine daily performance analysis of RWH systems with life cycle cost analysis for use in economic evaluation, and showed that the recent tendency towards smaller tanks in Australia is a poor choice economically, that RWH system in Kenya can be economically beneficial if installed without reticulation, and reliability (the percentage of days that the demand is met) can be a financial issue.

Journal ArticleDOI
TL;DR: An application of a remote sensing data fusion technique for developing high spatiotemporal resolution maps of evapotranspiration (ET) at scales that can be associated with changes in land use over the Sacramento-San Joaquin Delta region in California is presented.
Abstract: The ability to accurately monitor and anticipate changes in consumptive water use associated with changing land use and land management is critical to developing sustainable water management strategies in water-limited climatic regions. In this paper, we present an application of a remote sensing data fusion technique for developing high spatiotemporal resolution maps of evapotranspiration (ET) at scales that can be associated with changes in land use. The fusion approach combines ET map timeseries developed using an multi-scale energy balance algorithm applied to thermal data from Earth observation platforms with high spatial but low temporal resolution (e.g., Landsat) and with moderate resolution but frequent temporal coverage (e.g., MODIS (Moderate Resolution Imaging Spectroradiometer)). The approach is applied over the Sacramento-San Joaquin Delta region in California—an area critical to both agricultural production and drinking water supply within the state that has recently experienced stresses on water resources due to a multi-year (2012–2017) extreme drought. ET “datacubes” with 30-m resolution and daily timesteps were constructed for the 2015–2016 water years and related to detailed maps of land use developed at the same spatial scale. The ET retrievals are evaluated at flux sites over multiple land covers to establish a metric of accuracy in the annual water use estimates, yielding root-mean-square errors of 1.0, 0.8, and 0.3 mm day−1 at daily, monthly, and yearly timesteps, respectively, for all sites combined. Annual ET averaged over the Delta changed only 3 mm year−1 between water years, from 822 to 819 mm year−1, translating to an area-integrated total change in consumptive water use of seven thousand acre-feet (TAF). Changes were largest in areas with recorded land-use change between water years—most significantly, fallowing of crop land presumably in response to reductions in water availability and allocations due to the drought. Moreover, the time evolution in water use associated with wetland restoration—an effort aimed at reducing subsidence and carbon emissions within the inner Delta—is assessed using a sample wetland chronosequence. Region-specific matrices of consumptive water use associated with land use changes may be an effective tool for policymakers and farmers to understand how land use conversion could impact consumptive use and demand.

Journal ArticleDOI
TL;DR: In this paper, the authors assess the linkages between biophysico-chemical water quality parameters and land use and land cover (LULC) classes in the upper reaches of the uMngeni Catchment, a rapidly developing catchment in South Africa.
Abstract: Land use and land cover change are major drivers of water quality deterioration in watercourses and impoundments. However, understanding of the spatial and temporal variability of land use change characteristics and their link to water quality parameters in catchments is limited. As a contribution to address this limitation, the objective of this study is to assess the linkages between biophysico-chemical water quality parameters and land use and land cover (LULC) classes in the upper reaches of the uMngeni Catchment, a rapidly developing catchment in South Africa. These were assessed using Geographic Information Systems tools and statistical analyses for the years 1994, 2000, 2008 and 2011 based on changes over time of eight LULC classes and available water quality information. Natural vegetation, forest plantations and cultivated areas occupy 85% of the catchment. Cultivated, urban/built-up and degraded areas increased by 6%, 4.5% and 3%, respectively coinciding with a decrease in natural vegetation by 17%. Variability in the concentration of water quality parameters from 1994 to 2011 and an overall decline in water quality were observed. Escherichia coli (E. coli) levels exceeding the recommended guidelines for recreation and public health protection was noted as a major issue at seven of the nine sampling points. Overall, water supply reservoirs in the catchment retained over 20% of nutrients and over 85% of E. coli entering them. A relationship between land use types and water quality variables was found. However, the degree and magnitude of the associations varies between sub-catchments and is difficult to quantify. This highlights the complexity and the site-specific nature of relationships between land use types and water quality parameters in the catchment. Thus, this study provides useful findings on the general relationship between land use and land cover and water quality degradation, but highlights the risks of applying simple relationships or adding complex relationships in the management of the catchment.

Journal ArticleDOI
TL;DR: The results show that a number of socioeconomic drought events (including some extreme ones) may occur in future, and the appropriate reservoir operation can significantly ease such situation.

Journal ArticleDOI
TL;DR: In this paper, the authors developed an iterative multi-method decision-making under uncertainty approach, including scenario generation, coproduction with stakeholders and water resources modeling, to explore the robustness of adaptation options and pathways against future climate and socioeconomic uncertainties in the Cauvery River Basin in Karnataka, India.
Abstract: Decision-Making Under Uncertainty (DMUU) approaches have been less utilized in developing countries than developed countries for water resources contexts. High climate vulnerability and rapid socioeconomic change often characterize developing country contexts, making DMUU approaches relevant. We develop an iterative multi-method DMUU approach, including scenario generation, coproduction with stakeholders and water resources modeling. We apply this approach to explore the robustness of adaptation options and pathways against future climate and socioeconomic uncertainties in the Cauvery River Basin in Karnataka, India. A water resources model is calibrated and validated satisfactorily using observed streamflow. Plausible future changes in Indian Summer Monsoon (ISM) precipitation and water demand are used to drive simulations of water resources from 2021 to 2055. Two stakeholder-identified decision-critical metrics are examined: a basin-wide metric comprising legal instream flow requirements for the downstream state of Tamil Nadu, and a local metric comprising water supply reliability to Bangalore city. In model simulations, the ability to satisfy these performance metrics without adaptation is reduced under almost all scenarios. Implementing adaptation options can partially offset the negative impacts of change. Sequencing of options according to stakeholder priorities into Adaptation Pathways affects metric satisfaction. Early focus on agricultural demand management improves the robustness of pathways but trade-offs emerge between intrabasin and basin-wide water availability. We demonstrate that the fine balance between water availability and demand is vulnerable to future changes and uncertainty. Despite current and long-term planning challenges, stakeholders in developing countries may engage meaningfully in coproduction approaches for adaptation decision-making under deep uncertainty.

Journal ArticleDOI
TL;DR: The proposed irrigation water quality index (IWQI), which is based on 12 parameters, classifies the water into five categories, viz. excellent, good, medium, bad, and very bad in the same manner as given by the CPCB and CGWB.
Abstract: Agriculture is a major sector in India which contributes around 14% of country's gross domestic product (GDP). Being an agriculture-based country, good quality of water for irrigation has been a prime requisite. Highly growing population and accelerated industrial development are causing anthropogenic pollution to both surface and groundwater on one side and geogenic contamination like arsenic, fluoride, high dissolved solids, sodicity, and iron in groundwater on other side. As a result, ensuring safe water quality for the irrigation has become a major challenge to both the central and state governments. The present irrigation water quality standards being followed in India have been set by the Central Pollution Control Board (CPCB) and Central Ground Water Board (CGWB) in the year 2000. These standards are solely based on four parameters, namely electrical conductivity, sodium percentage, sodium absorption ratio, and residual sodium carbonate, which are quite subjective and many times are not capable to exactly decide the quality of irrigation water particularly when there are large variations in the source water quality. Therefore, in the present paper, an indices-based approach is presented for categorization of irrigation water quality. These indices are mathematical equations that transform water quality data into a numeric value, which describes the quality of irrigation water. The proposed irrigation water quality index (IWQI), which is based on 12 parameters, classifies the water into five categories, viz. excellent, good, medium, bad, and very bad in the same manner as given by the CPCB and CGWB. In order to give proper rating to various parameters of the index, weights are computed using Saaty's analytic hierarchy process (AHP)-based multiple criteria decision analysis (MCDA) approach. This approach minimizes the subjectivity in assessment of weights and improves understanding of water quality issues by generating an overall index to describe the status of water quality. The proposed index will be beneficial for the water management authorities in ensuring safe water to the stakeholders.