Global water security is threatened by rising inequality

HighlightsWe provide context and perspectives on 13 articles in the Global Water Security collection.Limited irrigation, precision irrigation, and sustainable water resources management were critical themes.The collection emphasizes the need for adopting location-specific technologies to achieve global water security.Advances in data acquisition, data analysis, and modeling should be utilized to aid managing water resources. Abstract. This article introduces the Global Water Security collection in this issue of Transactions of the ASABE and issue 36(1) of Applied Engineering in Agriculture. Researchers, educators, industry partners, agricultural producers, and policymakers from 19 countries met at Hyderabad, India, to discuss critical issues and advancements at the Global Water Security Conference for Agriculture and Natural Resources. The conference was organized jointly by ASABE and the Indian Society of Agricultural Engineers (ISAE). This special collection consists of 13 articles selected from the 245 meeting presentations as well as invited articles. A perspectives article in this collection summarizes seven key priorities identified for action at the conference: reduce food waste, increase wastewater reuse, increase agricultural resiliency and efficiency, optimize irrigation efficiency and increase crop water productivity, improve water supply management, improve water resource infrastructure, and enhance water resource decision-making and policy formulation. The remaining 12 articles address a wide range of water security topics grouped by four themes: sustainable management of water resources (3 articles), limited irrigation for water conservation (5 articles), precision irrigation management (2 articles), and water management in hilly regions (2 articles). While these articles are not inclusive of all water security challenges in the agriculture and natural resources sectors, they highlight selected important challenges and potential solutions. The research presented in this special collection emphasizes the importance of developing and using appropriate location-specific technologies that increase water application efficiency and water use efficiency while maintaining adequate water supplies for natural resource functions and ecosystem services to ensure global water security. Keywords: Climate change, Crop water productivity, Food security, Irrigation efficiency, Natural resource policy, Wastewater reuse, Water resource infrastructure, Water scarcity.

Ensuring universal and equitable access to water and sanitation for all by 2030 (United Nations Agenda 2030, Sustainable Development Goal or SDG 6) is one of the most important goals for the world. 785 million people do not still have access to basic drinking water services. This burden disproportionately affects women, who are often responsible for collecting water from distant sources in regions with limited or no water supply systems. Understanding the spatial patterns of socio-demographic and hydrological factors is key to address the interlinked challenges of gender equality and water security under SDG 5 (‘Achieve gender equality’) and SDG 6. While the challenges women face in securing water are widely recognized, quantitative analysis of gender inequality in global water security has not previously been studied. Here, we present, to our knowledge the first global assessment of gender inequality in water security. We measured water security by examining both water access and water scarcity (hereafter, water stress), incorporating population data for working-age individuals and children. We integrated this hydrological and demographic information at a spatial resolution of approximately 10 km from 2000 to 2014 when the information is available. Our results showed that more working-age women than men experience poor water access, particularly in Africa. In addition, women in countries with high water insecurity, defined as high water stress and poor water access—such as Burkina Faso, Togo, and Somalia—primary conduct water collection. Our results indicate significant gender-based differences in water security, with women frequently remaining in rural areas characterized by poor water access. These inequalities could be further intensified by climate change and socio-economic factors.

Global water security: A shining star in the dark sky of achieving the sustainable development goals

HighlightsSugarcane hybrids with improved IWUE have greater scope in sugarcane agriculture as irrigation water is getting scarce.Among sugarcane hybrids, Co 8371 registered high mean water productivity of 4.18 kg m-3, followed by Co 85019 (3.92 kg m-3), while in I2, six hybrids had significantly higher water productivity (Co 85019, Co 0212, Co 86249, Co 10026, Co 0218 and Co V92102) above 4 kg m-3.Deficit irrigation scheduling (irrigation at recommended interval, with 50% crop evapotranspiration replacement) appears to be far more useful than reducing frequency as well as quantity of irrigation water alone. Hybrid mean water productivity was 3.2, 2.7, and 2.1 kg m-3 in I0, I1, and I2, respectively.ABSTRACT. The escalating deficit rainfall scenario in India indicates that drought is a recurrent phenomenon associated with tropical sugarcane farming, and the availability of irrigation water for sugarcane cultivation will be much less in coming years. To meet the challenge of limited and costly water supply, tropical sugarcane growers will have to find ways of increasing the efficiency of irrigation to maintain high cane yields. More efficient irrigation systems, accurate irrigation scheduling, and the right choice of sugarcane hybrids are potential means of increasing irrigation water use efficiency (IWUE), water productivity (WP), and global water security. With the objective of optimizing irrigation water use, a field experiment evaluating the physiological efficiency of commercial sugarcane hybrids for WP in a sandy clay soil under water-limited conditions was conducted during 2016-2017 at the ICAR-Sugarcane Breeding Institute in Coimbatore, India. The replicated field experiment was laid out in split-plot design with three irrigation levels as the main plot and 33 sugarcane hybrids as subplots. The prevailing climatic conditions during the experiment represented a tropical wet and dry climate, with the wet season lasting from October to December due to the northeast monsoon. The results showed that full irrigation at recommended intervals with 100% crop evapotranspiration (ET) replacement (I0) produced significantly higher cane yield than deficit irrigation at recommended intervals with 50% crop ET replacement (I1) and skipping alternate irrigations with 50% crop ET replacement (I2). The deficit irrigation treatments (I1 and I2) had declines in cane yield of 41.2% and 56.4%, respectively. IWUE was similar in I0 and I1, while I2 had reduced IWUE by 23%. WP was significantly influenced by irrigation level; reduction in irrigation water reduced WP by 17.5% and 36.3% in I1 and I2 compared to I0. Among sugarcane hybrids, Co 85019, Co 13006, Co 10026, Co 99004, CoLk 8102, Co 86249, Co 8371, Co 94008, and Co 95020 yielded higher than the genotypic mean under both deficit irrigation treatments, suggesting their usefulness in deficit irrigation strategies. Sugarcane hybrids with high WP can play a pivotal role in sustaining sugarcane productivity and can reduce the large volumes of irrigation water consumed in water-scarce tropical India. Thus, considering water security, the implications of the results are of paramount importance in promoting the coordinated development and management of water, land, and related resources to maximize economic benefits and social welfare in an equitable manner without compromising the sustainability of vital ecosystems at local as well as national levels. Keywords: Cane yield, Global water security, Sugarcane, Water-limited condition.

HighlightsASABE and ISAE convened the Global Water Security Conference for Agriculture and Natural Resources in Hyderabad, India, in 2018.Recommendations represent collective contribution of attendees and presenters in seven key priorities.Continuation of a narrow focus on technical aspects will likely prevent the success of technical solutions.Scientists and engineers should work together across all disciplines and boundaries to ensure global water security. Keywords: Climate change, Crop water productivity, Food security, Irrigation efficiency, Natural resource policy, Wastewater reuse, Water resource infrastructure, Water scarcity.

Water security and climate change are only two of the major long-term problems the world is facing at present. Increasing population, urbanisation and demands for a better quality of life all over the world mean more food, energy and other resources will be necessary in the future. Increasing food and energy supplies will require more efficient water management all over the production and supply chains. All these requirements have to be met in a way so that significantly less greenhouse gases are emitted into the atmosphere which are contributing to climate change at an increasing scale. Historically, the total global water demands have steadily increased. Currently, about 70% of global water is used by agriculture, 20% by industry and 10% by domestic. In all these three use areas, there is enough knowledge available to reduce water requirements very significantly. Agricultural production can be very substantially increased with much lower water requirements. Domestic and industrial wastewaters can be collected, treated and reused. With proper management, this virtuous cycle can be a reality. While conceptually global water security can be assured by using current knowledge, climate change considerations have made ensuring global water security a very complex task. This is because major uncertainties are associated with any forecast of future extreme rainfalls and then translating them into runoffs in river basins and sub-basins which often are units of planning. This chapter reviews and assesses what can be done to ensure water security for individual countries as well as the world as a whole. Thereafter, it analyses the risks and uncertainties that policymakers and water professionals are likely to face in dealing with climate change through the lens of water security.

Water plays an important role in underpinning equitable, stable and productive societies and ecosystems. Hence, United Nations recognized ensuring water security as one (Goal 6) of the seventeen sustainable development goals (SDGs). Many international river basins are likely to experience ‘low water security’ over the coming decades. Water security is rooted not only in the physical availability of freshwater resources relative to water demand, but also on social and economic factors (e.g. sound water planning and management approaches, institutional capacity to provide water services, sustainable economic policies). Until recently, advanced tools and methods are available for the assessment of water scarcity. However, quantitative and integrated—physical and socio-economic—approaches for spatial analysis of water security at global level are not available yet. In this study, we present a spatial multi-criteria analysis framework to provide a global assessment of water security. The selected indicators are based on Goal 6 of SDGs. The term ‘security’ is conceptualized as a function of ‘availability’, ‘accessibility to services’, ‘safety and quality’, and ‘management’. The proposed global water security index (GWSI) is calculated by aggregating indicator values on a pixel-by-pixel basis, using the ordered weighted average method, which allows for the exploration of the sensitivity of final maps to different attitudes of hypothetical policy makers. Our assessment suggests that countries of Africa, South Asia and Middle East experience very low water security. Other areas of high water scarcity, such as some parts of United States, Australia and Southern Europe, show better GWSI values, due to good performance of management, safety and quality, and accessibility. The GWSI maps show the areas of the world in which integrated strategies are needed to achieve water related targets of the SDGs particularly in the African and Asian continents.

Water has been ranked first among the top five global risks in terms of social impact. Yet, the vision of water as a sustainability variable has lost strength to the detriment of the security concept. This paper proposes an approach of global water governance based on water security (WS) to respond to the increasing water shortage on the planet. The method involved the usage of qualitative procedures, the analysis of regulatory documents related to international water management, and the interviews of five experts within the management and regulation sectors. The process was useful in determining five main scopes and to articulate the framework to promote WS: first - risk as water management paradigms; secondly - review of the international regulatory framework and creation of a United Nation specialised agency for WS; thirdly - transversal link for WS between different actors; fourthly - applying WS mechanisms in river basins; fifthly - adoption of new analytical methods.

This paper delves into the pivotal role of cleaner production in the pursuit of global water security. Leveraging Biblioshiny, a robust bibliometric analysis tool based on R-Software, the paper examined Scopus data, following PICO protocols and PRISM guidelines. The study's findings underscore the potential of cleaner production strategies on wastewater to underpin water security. To this end, the study proffers three policy interventions: an "Industrial Cleaner Production Policy," a "Water Eutrophication Prevention Policy," and an "Environmental Sustainability Club Policy." These policies collectively constitute a comprehensive framework for ushering in an era of water security anchored in cleaner production principles. In conclusion, the study calls for the seamless integration of cleaner production into global discourse on water security, particularly within the United Nations framework, and its incorporation into various policy documents. This approach ensures cleaner production's central role as a multifaceted intervention tool, enhancing global commitment to water security.

The paper introduces some of the general challenges of global water security, particularly in poverty stricken regions such as Africa, and highlights the likely global impact of climate change, increasing pollution and population growth etc. on water resources, as outlined in recent studies. The nexus between water, food and energy is introduced, along with the concept of virtual water and the impact of the water footprint and the need for society, industry and governments to become more conscious of the water footprint, alongside the carbon footprint. Various practical solutions to enhancing security of supply are introduced and discussed, such as desalination and integrated water management in the form of ‘Cloud to Coast’, together with global actions needed. Finally, some water security challenges and opportunities for developed countries, such as the UK, are discussed, particularly with regard to the need to price water appropriately and the need to appreciate that the price of water should cover more than just the cost of delivery to the home. The paper concludes with the urgent need to raise the profile of global water security at all levels of society and through international bodies, for the benefit of humanity worldwide.KeywordsClimate changeWater resourcesWater pollutionWorld populationIntegrated water managementEco-systemsBio-diversityDesalinationWater pricing

Water has been ranked first among the top five global risks in terms of social impact. Yet, the vision of water as a sustainability variable has lost strength to the detriment of the security concept. This paper proposes an approach of global water governance based on water security (WS) to respond to the increasing water shortage on the planet. The method involved the usage of qualitative procedures, the analysis of regulatory documents related to international water management, and the interviews of five experts within the management and regulation sectors. The process was useful in determining five main scopes and to articulate the framework to promote WS: first - risk as water management paradigms; secondly - review of the international regulatory framework and creation of a United Nation specialised agency for WS; thirdly - transversal link for WS between different actors; fourthly - applying WS mechanisms in river basins; fifthly - adoption of new analytical methods.

Sustainable development demands reliable water resources, yet traditional water management has broadly failed to avoid environmental degradation and contain infrastructure costs. We explore the global-scale feasibility of combining natural capital with engineering-based (green-gray) approaches to meet water security threats over the 21st century. Threats to water resource systems are projected to rise throughout this period, together with a significant expansion in engineering deployments and progressive loss of natural capital. In many parts of the world, strong path dependencies are projected to arise from the legacy of prior environmental degradation that constrains future water management to a heavy reliance on engineering-based approaches. Elsewhere, retaining existing stocks of natural capital creates opportunities to employ blended green-gray water infrastructure. By 2050, annual engineering expenditures are projected to triple to $2.3 trillion, invested mainly in developing economies. In contrast, preserving natural capital for threat suppression represents a potential $3.0 trillion in avoided replacement costs by mid-century. Society pays a premium whenever these nature-based assets are lost, as the engineering costs necessary to achieve an equivalent level of threat management are, on average, twice as expensive. Countries projected to rapidly expand their engineering investments while losing natural capital will be most constrained in realizing green-gray water management. The situation is expected to be most restrictive across the developing world, where the economic, technical, and governance capacities to overcome such challenges remain limited. Our results demonstrate that policies that support blended green-gray approaches offer a pathway to future global water security but will require a strategic commitment to preserving natural capital. Absent such stewardship, the costs of water resource infrastructure and services will likely rise substantially and frustrate efforts to attain universal and sustainable water security.

<div> <p><span>Globally, the terrestrial water cycle is changing rapidly, because of human interventions in catchment hydrological processes, and changing meteorological boundary conditions. Many of these changes have a negative impact on the water security of people living within and nearby those catchments. Plenty of scientific evidence points to increasing intensities and frequencies of floods and droughts and degrading water resources in many parts of the world. While increasing water security is globally high on the policy agenda, there are clearly no easy solutions to this problem. Catchments are complex, idiosyncratic systems from which society draws many different resources and services, and many of these activities affect the local hydrological processes and the human benefits and risks that emanate from those.</span><span> </span></p> </div><div> <p><span>Achieving global water security is therefore only possible with solutions that are tailored to these specific local characteristics and realities. Analysing cases from the Andes, the Himalayas, and Africa, in this lecture I set out to identify crucial ingredients for successful catchment interventions, as well as some of the main scientific challenges that remain. I start from the conceptualization of a catchment as a complex adaptive system, governed by a unique combination of natural, social, and cultural processes.</span><span> </span></p> </div><div> <p><span>A first step then involves characterizing and quantifying these processes, which requires data collection and measuring. Although high-quality data are severely lacking in most of the world, many new opportunities are emerging. These range from remote sensing and pervasive in-situ sensor networks to novel data collection arrangements such as participatory monitoring and citizen science. In a next step, potential catchment interventions must be identified and evaluated. Also here, the toolbox of the catchment managers is growing continuously, with new concepts such as green infrastructure and nature-based solutions gaining traction. However, evaluating different potential interventions requires careful scenario analysis. Computational models, as well as uncertainty and risk assessment, are crucial tools to do so, but it also involves a thorough analysis of the (potentially complex and interacting) benefits and disbenefits that each intervention exerts on various population groups. Lastly, long term monitoring and evaluation of catchment interventions remains a formidable challenge, even though it is a crucial element to ensure that interventions effectively generate the anticipated benefits, to mitigate unexpected side-effects, and to adjust and adapt to constantly changing boundary conditions and catchment dynamics.</span></p> </div>

The increase in global water insecurity is one of the first perceivable effects of climate change. Two billion people are now without access to safe drinking water, and four billion experience water stress at least once a year, primarily in low per-capita emission countries. This nexus between climate change and water insecurity has significant implications for the global economy, with the water sector contributing 10% of global emissions. Though traditionally a local issue, climate finance mechanisms like the voluntary carbon market (VCM) present opportunities for a global, sustainable, performance-based funding stream to address water insecurity. Since 2010, water-related carbon projects have yielded over 45 million emission reduction credits. Our analysis estimates a global potential of over 1.6 billion tCO2e per year across various water project subsectors. At a $10 per credit average, this could attract over $160 billion in investments over the next decade, enhancing global water security. However, barriers like high intervention costs and limited technologies hinder widespread implementation, creating a tension between standardized and bespoke credits. We present case studies, spanning drinking water initiatives to the wastewater treatment sector that illustrate VCM's role in channeling private sector capital for water security in climate-vulnerable regions.

The overarching goals for the UK in relation to global water security are to; tackle and reverse growing water insecurity and its consequences caused by depletion and degradation of natural water sources; and address poor water management and increasing demand. To do this, the UK has a well-developed water ‘offer’ that together can help reach the goal of global water security. This note details some of that water offer: UK water leadership: The UK developed the concept of modern sanitation and water supply, with an early example being the Victorian Bazalgette London sewer; Ownership and regulation: The UK has four models of ownership: government department in Northern Ireland, GoCo in Scotland, Mutual in Wales, and private companies in England. But the common thread is strong and clear, regulation to deliver the right outcomes for society; Competition and markets: The UK set up the world’s first water retail markets for business customers, delivering savings and environmental benefits. Similar market mechanisms are being developed for sewage sludge, which will help drive circular economy solutions; Innovation: The UK has a huge number of water tech start-ups and most water companies have labs and pilot schemes to support these fledgling companies. At the same time, the English regulator, Ofwat, has established a huge innovation fund, which along with the Scottish Hydro Nation initiative has made the UK the best place in the world for water innovation and tech.