research topics in water supply

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• 14 December 2023

The most important issue about water is not supply, but how it is used

• Peter Gleick 0

Peter Gleick is co-founder and a senior fellow at the Pacific Institute in Oakland, California. He is the author of The Three Ages of Water: Prehistoric Past, Imperiled Present, and a Hope for the Future (2023)

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Floods, droughts, pollution, water scarcity and conflict — humanity’s relationship with water is deteriorating, and it is threatening our health and well-being, as well as that of the environment that sustains us. The good news is that a transition from the water policies and technologies of past centuries to more effective and equitable ways of using and preserving this vital resource is not only possible, but under way. The challenge is to accelerate and broaden the transition.

Water policies have typically fostered a reliance on centralized, often massive infrastructure, such as big dams for flood and drought protection, and aqueducts and pipelines to move water long distances. Governments have also created narrow institutions focused on water, to the detriment of the interconnected issues of food security, climate, energy and ecosystem health. The key assumption of these ‘hard path’ strategies is that society must find more and more supply to meet what was assumed to be never-ending increases in demand.

Nature Outlook: Water

That focus on supply has brought great benefits to many people, but it has also had unintended and increasingly negative consequences. Among these are the failure to provide safe water and sanitation to all; unsustainable overdraft of ground water to produce the food and fibre that the world’s 8 billion people need; inadequate regulation of water pollutants; massive ecological disruption of aquatic ecosystems; political and violent conflict over water resources; and now, accelerating climate disruption to water systems 1 .

A shift away from the supply-oriented hard path is possible — and necessary. Central to this change will be a transition to a focus on demand, efficiency and reuse, and on protecting and restoring ecosystems harmed by centuries of abuse. Society must move away from thinking about how to take more water from already over-tapped rivers, lakes and aquifers, and instead find ways to do the things we want with less water. These include, water technologies to transform industries and allow people to grow more food; appliances to reduce the amount of water used to flush toilets, and wash clothes and dishes; finding and plugging leaks in water-distribution systems and homes; and collecting, treating and reusing waste water.

Remarkably, and unbeknown to most people, the transition to a more efficient and sustainable future is already under way.

Singapore and Israel, two highly water-stressed regions, use much less water per person than do other high-income countries, and they recycle, treat and reuse more than 80% of their waste water 2 . New technologies, including precision irrigation, real-time soil-moisture monitoring and highly localized weather-forecasting models, allow farmers to boost yields and crop quality while cutting water use. Damaging, costly and dangerous dams are being removed, helping to restore rivers and fisheries.

Source: US Geological Survey

In the United States, total water use is decreasing even though the population and the economy are expanding. Water withdrawals are much less today than they were 50 years ago (see ‘A dip in use’) — evidence that an efficiency revolution is under way. And the United States is indeed doing more with less, because during this time, there has been a marked increase in the economic productivity of water use, measured as units of gross domestic product per unit of water used (see ‘Doing more with less’). Similar trends are evident in many other countries.

Source: US Geological Survey/US Department of Commerce.

Overcoming barriers

The challenge is how to accelerate this transition and overcome barriers to more sustainable and equitable water systems. One important obstacle is the lack of adequate financing and investment in expanding, upgrading and maintaining water systems. Others are institutional resistance in the form of weak or misdirected regulations, antiquated water-rights laws, and inadequate training of water managers with outdated ideas and tools. Another is blind adherence by authorities to old-fashioned ideas or simple ignorance about both the risks of the hard path and the potential of alternatives.

Funding for the modernization of water systems must be increased. In the United States, President Biden’s Infrastructure Investment and Jobs Act provides US$82.5 billion for water-related programmes, including removing toxic lead pipes and providing water services to long-neglected front-line communities. These communities include those dependent on unregulated rural water systems, farm-worker communities in California’s Central Valley, Indigenous populations and those in low-income urban centres with deteriorating infrastructure. That’s a good start. But more public- and private-investments are needed, especially to provide modern water and sanitation systems globally for those who still lack them, and to improve efficiency and reuse.

Regulations have been helpful in setting standards to cut waste and improve water quality, but further standards — and stronger enforcement — are needed to protect against new pollutants. Providing information on how to cut food waste on farms and in food processing, and how to shift diets to less water-intensive food choices can help producers and consumers to reduce their water footprints 3 . Corporations must expand water stewardship efforts in their operations and supply chains. Water institutions must be reformed and integrated with those that deal with energy and climate challenges. And we must return water to the environment to restore ecological systems that, in turn, protect human health and well-being.

In short, the status quo is not acceptable. Efforts must be made at all levels to accelerate the shift from simply supplying more water to meeting human and ecological water needs as carefully and efficiently as possible. No new technologies need to be invented for this to happen, and the economic costs of the transition are much less than the costs of failing to do so. Individuals, communities, corporations and governments all have a part to play. A sustainable water future is possible if we choose the right path.

doi: https://doi.org/10.1038/d41586-023-03899-2

This article is part of Nature Outlook: Water , a supplement produced with financial support from the FII Institute. Nature maintains full independence in all editorial decisions related to the content. About this content .

Caretta, M. A. et al . In: Climate Change 2022: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (eds Portner, H.-O. et al .) 551–712 (Cambridge Univ. Press, 2022)

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Faster and Safer: Research Priorities in Water and Health

Karen setty.

a The Water Institute at University of North Carolina at Chapel Hill, Department of Environmental Sciences and Engineering, 166 Rosenau Hall, CB #7431, Chapel Hill, NC, 27599-7431;

Jean-Francois Loret

b Suez, Centre International de Recherche sur l’Eau et l’Environnement (CIRSEE), 38 rue du President Wilson, 78230, Le Pecq, France;

Sophie Courtois

Charlotte christiane hammer.

c Norwich Medical School, University of East Anglia Faculty of Medicine and Health Sciences, Norwich, NR4 7TJ, UK;

Philippe Hartemann

d Université de Lorraine, Faculté de Médecine, EA 7298, ERAMBO, DESP, Vandœuvre-lès-Nancy, France;

Michel Lafforgue

e Suez Consulting, Le Bruyère 2000 - Bâtiment 1, Zone du Millénaire, 650 Rue Henri Becquerel, CS79542, 34961, Montpellier Cedex 2, France;

Xavier Litrico

f Suez, Tour CB21, 16 Place de l’Iris, 92040 Paris La Defense Cedex, France;

Tarek Manasfi

g Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland;

Gertjan Medema

h KWR Watercycle Research Institute, Groningenhaven 7, 3433 PE, Nieuwegein, The Netherlands;

i Delft University of Technology, Stevinweg 1, 2628 CN, Delft, The Netherlands

Mohamed Shaheen

j School of Public Health, University of Alberta, 3-300 Edmonton Clinic Health Academy, 11405 - 87 Ave, Edmonton, AB T6G 1C9, Canada;

Vincent Tesson

k French National Institute for Agricultural Research (INRA), UMR 1114 EMMAH, 228 route de l’Aérodrome, CS 40 509, 84914 Avignon Cedex 9, France;

Jamie Bartram

The United Nations’ Sustainable Development Goals initiated in 2016 reiterated the need for safe water and healthy lives across the globe. The tenth anniversary meeting of the International Water and Health Seminar in 2018 brought together experts, students, and practitioners, setting the stage for development of an inclusive and evidence-based research agenda on water and health. Data collection relied on a nominal group technique gathering perceived research priorities as well as underlying drivers and adaptation needs. Under a common driver of public health protection, primary research priorities included the socioeconomy of water, risk assessment and management, and improved monitoring methods and intelligence. Adaptations stemming from these drivers included translating existing knowledge to providing safe and timely services to support the diversity of human water needs. Our findings present a comprehensive agenda of topics at the forefront of water and health research. This information can frame and inform collective efforts of water and health researchers over the coming decades, contributing to improved water services, public health, and socioeconomic outcomes.

Introduction

To promote public health and wellbeing, the United Nations’ Sustainable Development Goal (SDG) 6 seeks to “ensure availability and sustainable management of water and sanitation for all” by 2030 ( UN Water, 2018 ). Many entities are scaling up efforts to address this challenge, including responses to the new aspects of SDG 6 as compared to the earlier Millennium Development Goals (1990–2015). These aspects include universality, inclusivity, cooperative participation, and “safely managed” services, as well as improved coordination with environmental protection efforts to support integrated water resource management. Evidence-informed decision-making (EIDM) is a common goal in many service provision sectors, including water, sanitation, and hygiene (WaSH). Barriers to the use of EIDM in WaSH policy and practice have included a weak enabling environment, bounded by relatively low political priority, lack of mutual accountability, poor coordination, insufficient financing, and limited data availability or relevance ( SWA, 2018 ). Because the transition to SDG 6 is accompanied by new evidence needs, it requires review of corresponding research priorities ( Setty et al., 2018b ).

Research on water and health involves both quantitative and qualitative studies, generating and matching data from a complex mixture of disciplines, such as environmental science, engineering, epidemiology, economics, hydrology, chemistry, microbiology, toxicology, human biology, sociology, anthropology, statistics, and geospatial mapping. Interventions to change processes or behaviors to improve public health are often complex. Unlike medical trials, it can be difficult to implement WaSH interventions in a controlled way, or to blind researchers and participants to randomized assignment. Some of these challenges are exacerbated in low-income settings, leading to weak main effects and strong contextual influences ( Hamilton and Mittman, 2017 ). The resulting evidence base is characterized by heterogeneity with highly variable effects dependent on site-specific characteristics. The state of evidence in WaSH may exasperate decision-makers, who look for clear, usable, and immediate guidance when policy windows open ( Brocklehurst, 2013 ; Rose et al., 2017 ).

A number of international events focus on water and health topics, including World Water Week in Stockholm, the rotating International Water Association World Water Congress and Exhibition, and the Water and Health conference in Chapel Hill, North Carolina. These events draw hundreds to thousands of participants. Since 2009, the multinational utility company Suez has likewise organized an International Water and Health Seminar annually in Cannes, France to promote meaningful exchange between researchers and practitioners. It invites senior academic experts and junior scientists (typically finishing PhD students) into a smaller forum with greater contact time. Participating experts form a standing scientific committee, and new student participants apply to attend each year. Typically, the scientific committee selects 16–20 PhD students to maximize geographical and topic diversity. Attendees have come from countries including Australia, Brazil, Canada, China, Denmark, Egypt, England, Finland, France, Germany, Hungary, Iceland, South Africa, Spain, Sweden, Switzerland, Tunisia, the United States, and Wales.

We set out to explore water and health research priorities by harvesting the perspectives of participants at the 2018 International Water and Health Seminar. All participants joined a simplified nominal group technique (NGT) exercise that explored drivers, adaptation needs, and perceived research priorities. Ideally, research priority setting should be transparent, consider context, take a comprehensive stance, establish focal criteria, and include multiple categories of stakeholders ( Viergever et al., 2010 ). The NGT approach is often used in quality improvement, business, and other group settings to engender active and equal participation, and to achieve prioritization and consensus ( CDC, 2006 ; Tague, 2004 ).

We applied a simplified and slightly modified NGT ( CDC, 2006 ; Tague, 2004 ) including all participants at the 2018 International Water and Health Seminar held in Cannes, France. This in-person, participatory method was selected as a structured and inclusive way to develop consensus among a fairly large and mixed group of researchers and practitioners (water and sanitation service providers). It aimed to achieve theoretical saturation (comprehensive exploration of research themes) by not limiting the number of submissions per person and triangulating concepts through multiple rounds of inquiry ( Saunders et al., 2018 ). The technique was adapted because of time constraints, and used a color indicator for paper submissions to confidentially record, and permit analysis of, differences in perceptions among the three types of participants: academics, students, and practitioners. We also examined past programs and prepared summary statistics to compare results to presentation topics from the first ten years of the seminar (2009–2018). Owing to the expansive topic, data interpretation included a group-based narrative review ( Dijkers, 2009 ) focused on the most pertinent literature relevant to each research theme.

Data collection

Thirty-three participants (8 senior academic researchers, 10 Suez research staff members, and 15 doctoral or postdoctoral scholars) attended the seminar. All agreed to participate in the NGT exercise. No compensation was offered, nor any penalty for choosing not to participate. Most participants came from Europe, with representatives from the US, Canada, and Australia; names, classifications, and institutions of participants are listed in the acknowledgements. The students were at an advanced trainee level in their careers, pursuing pre- or postdoctoral research, while the academics held advanced degrees and professorships and were generally late career. Professional attendees ranged from early- to mid- to late-career and were permanent or contract employees of research and development branches within Suez, a large multinational utility group headquartered in France. The seminar and NGT sessions were conducted in English, which was a second language for some participants. In consultation with the University of North Carolina at Chapel Hill Office of Human Research Ethics, the study was not submitted for formal IRB approval because the information gathered related to the research needs assessment rather than the participants themselves.

Five days before the seminar, all participants received an email with written instructions concerning the exercise. Participants were asked to consider questions about water and health research priorities, but not to share their ideas with others. The scope of “water and health” was deliberately not defined, as the scope of understanding of the term was itself of interest. The instructions requested feedback at the seminar on research themes separately from research questions, but during the exercise these categories were merged and a new question was added on adaptations to the underlying drivers.

At the seminar, two sessions of NGT were conducted. In each, no prior knowledge of the instructions was assumed and participants were briefly introduced to the question(s) to be tackled. Ten to twelve minutes were dedicated to “silent idea generation” in which participants recorded each of their ideas on sticky note paper, with different colors to differentiate ideas from different participant groups (students, academics, and practitioners). The practice of writing responses before sharing ensured accountability to the original idea and equal participation, to prevent cognitive “anchoring and adjustment” or reporting bias based on what others shared with the group. The facilitator (JB) served as a participant in accordance with good practice for NGT.

Method modifications of standard NGT ( CDC, 2006 ; Tague, 2004 ) included (a) accepting clustered contributions after the first round, and (b) performing counting for prioritization afterwards, following electronic data entry. One round of round-robin idea presentation was conducted in which each participant described one idea from their sticky notes and the note was added to a display board. Notes were loosely organized into categories, typically proposed by the person who first raised a new idea, and grouped by joining similar submissions as themes emerged. Subsequent rounds proceeded similarly, except that to conserve time, individuals were permitted to offer up notes duplicative of or similar to an idea being presented at any time, without waiting for their next turn, keeping them in the same grouping with the original idea. Rounds continued until all ideas were exhausted. Participants then checked the results on the boards, discussed, and modified the idea organization and groupings. The outcome was adopted by informal consensus and transcribed into an electronic record.

The first round involved all groups of participants (students, academics, and practitioners) and lasted approximately two hours. It addressed two questions (drivers and research questions), and participants indicated at the time of presentation whether the idea they were presenting was a driver or a research question/theme. The second session took place two days after the first, and lasted approximately two hours. It addressed practical adaptations to the drivers and involved only the academics and practitioners, as students were assumed to have less applied experience.

Data processing

We inductively compared responses based on the three different approaches using different questions ( Figure 1 ) to identify prominent research priorities, underlying drivers, and adaptations. A research agenda was constructed primarily using input on research questions, with cross-comparison for sensitivity to drivers and adaptations. The participant input was similarly cross-compared with prior program topics gleaned from annual programs from 2009–2018. This data triangulation helped to ensure missing topics and perspectives were covered. Several authors separately assessed data via conventional qualitative content analysis ( Hsieh and Shannon, 2005 ), using line-by-line (in vivo) coding in most cases, to evaluate the frequency of subthemes as a basis for presentation of findings and discussion.

Relationship between three lines of inquiry pursued using the NGT method to support data triangulation and comprehension.

The relatively rapid sorting into themes at the in-person sessions was supplemented with follow-up checks involving two authors (JB and KS). Using the submitted research priorities and categorical organization as the primary input, category wording was harmonized to create a set of distinct concepts related to the umbrella of water and health. First, alternative categorization schemes were explored to determine which best fit the data. Second, categories with three or fewer nominated research topics were merged into other larger categories, and dominant subcategories were elevated to categories to create a relatively even distribution of topics. Third, each category assignment was reviewed and some research topics were reassigned, using the original wording of the submission and giving deference to the original category assignment if wording was unclear. Categories were ordered by frequency of topic nomination, counting each entry as one “vote,” as a means to convey overall prominence. Finally, the wording of each submission was revised to correct minor spelling and grammar errors, to help clearly convey the intended topic. In some cases, for example when inferring the meaning of acronyms, the most probably meaning in common use was assigned, although alternative meanings were possible.

Input based on submitted drivers and adaptations were reviewed and cross-compared with the research priorities, to identify gaps and novel insights. Additionally, the research priorities were compared with topics from the 10-year history of the Cannes seminar, to offer insight as to trends over time. This involved assignment of topics to themes by year by a third author (JFL). All participants were offered a follow-up opportunity to help with data interpretation and contribute to manuscript preparation. As a result, the draft results were shared with a sub-group of participants who volunteered, to continue to validate and refine understanding of the results in a participatory manner. This team-based approach engendered a narrative literature review of the most relevant references on each topic, to aid communication and uptake of the findings.

Participation

We tracked participant type, numbers of submitted “ideas,” and average per-person idea generation rates to characterize representation ( Table 1 ). Since no limit was assigned, the estimated number of submissions per individual ranged from approximately five to 25.

Number of participants and responses submitted at the seminar workshop by respondent type and round of questioning

Research priorities

Refinement of the draft topic categorization initiated at the in-person sessions helped to solidify eleven major themes capturing water and health research priorities ( Figure 2 ). A somewhat broad category about the social, political, economic and other context in which people use water was of greatest concern, reflecting increased attention toward sustainable global development and soft science in addition to engineering approaches. Next, some traditional disciplines such as water quality, water treatment, and water microbiology were prominent. Risk assessment and management, sanitation, and water resources held a moderate position. Less frequent emergent categories included information and artificial intelligence, real-time or rapid methods, water reuse, and the water-energy nexus. Some key subthemes also emerged across categories or nested within categories. These included technological innovation, metagenomics, “one health,” and disinfection.

Identified water and health research priorities, with themes and subthemes in order of frequency of research question submissions (in parentheses)

Triangulation

Using three different approaches (i.e., requesting research priorities directly versus asking indirectly about prevalent drivers and adaptations) allowed triangulation of the data from multiple perspectives. Similarities and differences among responses contributed to the framing of the research agenda. Overall, they revolved around protecting human health in the face of global changes as a critical underlying concept. Pure environmental (including wildlife and domestic animal) protection played a lesser role. Although deemed important by a number of participants, ecological sustainability represents a newer aspect of WaSH development goals. In many cases, environmental science, agriculture, and public health fields have traditionally had separate regulatory and research-funding structures, which may fail to promote disciplinary overlap. Shifts toward unified planetary health were recognized during participatory review of the study as a newer paradigm that will ultimately affect research drivers.

Drivers fell into seven categories: demographic change, climate, chemicals, microbes, infrastructure, nexus systems, and socio-political demands. In comparing drivers to the research themes, the perspective of drivers emphasized the health concerns underlying the research topics, which largely focused on water and sanitation services. Some categories overlapped with the research questions and themes. For instance, nexus-related topics captured energy ( Figure 2 ) as well as trends in food production, soil conditions, and shifting plant life. Climate change appeared as a prominent driver for weather-related risks, and was also mentioned under risk assessment and management ( Figure 2 ). Shifts in chemical production, especially of micropollutants, likewise linked to research questions under risk assessment and management, water quality, and water treatment.

Other driver topics were less prominent among the research questions. Sociopolitical shifts, such as increasing attention to equity and changing international relations, indirectly matched with the socioeconomy of water category, and thus might underlie all research themes. Commonly-referenced drivers for changes in service needs and water-related health vulnerabilities included demographic trends, such as population growth, aging populations, and migration (especially to urban areas). The research themes overlooked some drivers such as antimicrobial resistance and emerging diseases, both of which should fall under the water microbiology category. Aging infrastructure appeared as a prominent driver, but was mentioned less frequently as a research need, relative to information and artificial intelligence as well as water treatment.

Adaptations

Due to the smaller group size, the adaptations had fewer submitted ideas and in-seminar groupings. The main overlap with the research questions was a category called knowledge management and data science, corresponding to the information and artificial intelligence research category. Additional analysis revealed that the draft groupings of adaptations could be broken down further, and all research categories related to at least one adaptation idea submission. Secondary groupings related to the use of science to inform policy and regulations, as well as improved service provision. Subthemes included integration across systems, sectors, and exposures (e.g., engineering for complex systems with interdependencies and trade-offs); decentralization (e.g., of treatment infrastructure and monitoring capabilities); safety and surveillance, and responsiveness (e.g., to crises or situations of increased demand like migration or local droughts). In connection with sanitation, human biomonitoring (e.g., via sewage) emerged as a human health-oriented complement to established environmental health monitoring approaches. Such bridges address traditional divides between environmental protection and human health regulations. Surveillance responsibilities may be siloed among different entities, though, limiting rapid and effective communication and response.

Topics from prior seminar programs

Though presentation topics varied widely over the past ten years of the seminar (2009–2018), four primary categories could be identified: microbiology, chemistry, general topics (e.g., policies, modeling, risk management), and technology ( Figure 3 ). Subcategories further broke down these classifications. For water microbiology, Legionella , amoeba, and intra-amoebal pathogens were the most popular topics. For water quality, occurrence and treatment of micropollutants were prevalent in past seminars. Epidemiology and public health surveillance took the lead for the general category, mirroring the NGT adaptation topics. Biofiltration and biodegradation took the lead under technology. Additional prominent subcategories included pharmaceuticals and endocrine disruptors, antimicrobial resistance, nanomaterials, virus occurrence and treatment, perfluorates, and biofilms. Many of these topics matched those raised in the NGT sessions in 2018, although the prevalent terminology may have evolved over time. For instance, the microbiome and metagenomics appear more frequently in recent years, building on concepts prominent in earlier years such as biofilms and “viable but not culturable” bacterial cells.

Broad categorization of past seminar topics (2009–2018, inclusive)

Some previous presentation topics not mentioned in the NGT included specific viruses (e.g., Ebola, adenovirus, norovirus), parasites (e.g., Cryptosporidium ), and bacteria (enterotoxigenic Escherichia coli , Shigella , Helicobacter ), as well as perfluorinated chemicals, biofiltration, biodegradation, advanced oxidation, and recreational waters. These might reflect oversights, actual shifts in attention, or the wider stance requested for the exercise versus the specificity of individual research presentations, as these topics remain globally prominent. The focus on single pathogens, contaminants, or treatment approaches may also have given way to more holistic approaches to water safety, with the understanding that biological and chemical threats are constantly evolving. Surprisingly, the SDGs were not explicitly mentioned in the NGT, perhaps because they were recognized implicitly. Terrorism was a more prominent topic in past years, but in 2018 was included as one type of risk under risk assessment and management.

Contributors

The classification of submissions as coming from students, academics, or practitioners permitted observations about similarities and differences in perspective among stakeholder groups. In general, practitioners submitted more ideas than the academics or students, who provided roughly the same number of submissions. Past seminar topics were not broken down by contributor type, but came predominantly from academic and student attendees at the seminar, and reflected somewhat narrower topic specificity than the NGT.

Regarding drivers , students did not raise infrastructure issues. Among adaptations , few trends or contrasts were apparent in the diversity of suggestions by practitioners and academics. Within the knowledge management and data science category, practitioners dominantly raised real-time security. Within the research questions , all submissions on development of rapid or real-time monitoring methods and most submissions on the water-energy nexus and water reuse came from practitioners. Few students at the NGT expressed ideas about risk assessment and management or sanitation, although former students covered these topics in past seminars. Few academics addressed the socioeconomy of water, which may reflect a greater degree of specialization in other areas.

Within the umbrella topic of water and health, we present discussion around key themes and subthemes in order of decreasing frequency of participant submissions ( Figure 2 ). Aspects introduced through the data triangulation methods are integrated within the same thematic areas. The scope of participants’ understanding of “water and health” appeared to match the scope of the event itself, which focused on natural, social, and health sciences connected to water and wastewater services. It delved less frequently into water policy. Due to the natural overlap among these thematic categories, some topics were assigned to the closest fit while others appear in multiple contexts.

Socioeconomy of water

The socioeconomy of water concerns interactions of sociology, behavior, culture, and economics with water needs. Socioeconomic issues underlie many other water usage and safety concerns, as they make up the wider contextual structures in which water systems operate. This theme presents an opportunity to identify synergies among topics and issues, and traverse traditional disciplinary fields of research. Integration of different fields and novel combinations of viewpoints such as political ecology, international security, and anthropology can enhance understanding of the complexities of socioeconomic, socio-cultural, and broader water research questions, as well as their impacts on water safety and resilience. Integrated approaches can help to model complex systems ripe with interdependencies and trade-offs. Within this topic, contributions from participants broadly fit into three key subthemes: human factors, governance, and interdisciplinarity. Based on drivers, this theme must consider shifting international relations, demographic trends, and transboundary issues, such as increased migration. Considering the drivers and adaptations, aging infrastructure was another reality that will require added long-term investment and efficient planning ( Value of Water Campaign, 2017 ).

Human factors consist of attitudes, cultures, and practices. They include broad philosophical approaches towards the meaning of water ( Lycan, 2010 ) as well as applied issues such as perceptions and attitudes towards water conservation ( Tarlock, 1987 ; Hermanowicz, 2008 ) and wastewater reuse ( Po et al., 2003 ; Hartley, 2006 ). Further research in these fields should accompany future technological advances and socio-political changes, considering both their empirical and ethical implications for complex water systems. For instance, community-based and public participation in research processes may help redress inequities perpetuated by prevalent power dynamics in science ( Kemmis et al., 2016 ). Equity and social and environmental justice topics were underrepresented at the seminar, but may be a vital component of research context in both low- and high-income settings (e.g., Stillo and MacDonald Gibson, 2017 ). These contextual factors are likely to affect the selection and implementation of water and public health system interventions.

Governance issues include diverse settings from industrialized smart cities to resource-poor settings such as slums. In this field, research has focused on issues such as equitable and affordable access to safe water, which remains integral to accomplishing global development goals ( Onda et al., 2012 ). This subtheme spans access to piped water and wastewater disposal, as well as the health outcomes of limited access, for instance stemming from water carriage over large distances ( Geere et al., 2018 ; Sorenson et al., 2011 ). Water governance broadly encompasses situations of limited water ( Kummu et al., 2010 ) and increasing pressures from climate change across different world regions as diverse as Australia ( Dijk et al., 2013 ), the Middle East ( Hadadin et al., 2010 ), South Africa ( Mukheibir, 2008 ), China ( Cheng et al., 2009 ), and North America ( Gober and Kirkwood, 2010 ). Associated challenges for water conservation thus interact with many of the human factors mentioned above.

The third field concerns interdisciplinarity, transdisciplinarity, and the integration of social sciences, natural sciences, engineering, and operational research. This is at the forefront of many fields, especially in the context of “One Health” ( Min et al., 2013 ; Manlove et al., 2016 ), planetary health ( Galway et al., 2016 ), nutrition ( Picchioni et al., 2017 ), and other fields ( Morillo et al., 2003 ). Brown et al. (2015) mapped out how such an approach can lead to fruitful collaboration within and beyond the field of water research by forging a shared mission, developing “T-shaped” researchers, nurturing constructive dialogue, offering institutional support, and bridging research, policy, and practice. These approaches are especially important in water and health research due to the inherent integration of scientific inquiry with applied solutions in a complex socio-political environment. One example is the relationship between water and wastewater pricing and human behavior, where microeconomics (traditionally a business field) informs good water provision practices ( Nauges and Whittington, 2017 ).

Water quality

The notion of water quality, defined as measurement and understanding of how compounds and organisms in water can influence human and environmental health, has evolved alongside scientific and technical progress. It was essentially limited to organoleptic descriptors (color, odor, taste and temperature) until the early 19 th century ( Symons, 2006 ). The emergence of epidemiology and bacteriology resulted in the development of water disinfection and microbial indicators as new quality parameters, representing substantive public health achievements ( CDC, 1999 , Sedlak, 2014 ). Developments in analytical chemistry during the second half of the 20 th century led to an increasing number of new chemical parameters ( Trussel, 2006 ). The consciousness raised by a series of popular works (e.g., Carson, 1962 ; Colborn et al., 1996 ) likewise contributed to expanding the lists of quality parameters to encompass pesticides, pharmaceuticals, and endocrine disruptors. To measure and understand how compounds and organisms in water can influence human health, NGT participants recommended continued improvement in analytical methods for chemical and microbial contaminants. Subthemes raised by participants included microplastics, disinfection byproducts (DBPs), antimicrobial resistance, perfluorinated chemicals, toxicity detection, Water Safety Plans, and security issues. Microplastics have recently been an area of intense activity, especially in marine waters, but questions regarding their potential health effects on humans and the significance of waterborne exposure remain unanswered ( Rocha-Santos, 2018 ). DBPs remain major concern in drinking and recreational waters, with increased attention on understanding formation from different precursors, toxicity, and strategies to reduce or eliminate formation ( Li and Mitch, 2018 ; Manasfi et al., 2018 ). Antimicrobial resistance represents a major and increasing threat to public health, and the role of waste and drinking waters in the transmission of resistance genes needs to be clarified ( Manaia, 2017 , Wuijts, et al., 2017 ). Perfluorinated compounds such as PFOA and PFOS have gained increased public attention due to the potential health effects of levels found in source water and drinking water ( Morrison, 2016 ).

In-vitro bioassays for toxicity detection used for more than half a century to assess the safety of water reuse schemes have demonstrated their usefulness for the assessment of complex mixtures of pollutants. Their application, however, is still limited by lack of demonstration of the linkages between in-vitro and in-vivo response, and difficulty in interpreting results ( Leusch & Snyder, 2015 ). Water Safety Plans (incorporating water quality and security issues) have been recommended by the World Health Organization (WHO) since 2004 ( WHO, 2004 ) and are being deployed worldwide. Their application should lead to improved ways of assessing water quality using real-time parameters and on-line sensors for operational control (e.g., turbidity at filter outlet or intrusion detection), in addition to typically lengthier time-to-result laboratory analyses used for compliance.

Water treatment

Water treatment includes technology, infrastructure, and methods for ensuring safe water supply. Since water treatment technologies may be tailored to a range of sources including surface water, groundwater, marine water, stormwater, and recycled wastewater, this thematic area overlaps with water resources, water reuse, and sanitation. Ensuring safe water supply requires a holistic perspective and attention to four main subthemes: cost-effectiveness of treatment and treatment upgrades (e.g., membranes); avoidance or removal of chemical additives, DBPs, and emerging contaminants; alternatives for pathogen removal or disinfection; and ecological sustainability (e.g., safe disposal of brine waste from seawater desalination). An additional participant contribution focused on updating treatment technologies for distributed (cellular) systems and water reuse. In reference to drivers and adaptations, much of the world’s water treatment infrastructure was constructed in the latter half of the twentieth century, and is increasingly in need of repair or replacement ( Moe and Rheingans, 2006 ).

Updates to water treatment systems must take into account the best available technology, as well as cost, resilience, and environmental constraints. Cost-effectiveness and cost-benefit analyses require accessible methods (e.g., Whittington and Hanemann, 2006 ) that consider costs and benefits accrued beyond the utility, for instance to the public and the environment. Such plans are especially pertinent when planning to replace or repair infrastructure that can flexibly meet needs (e.g., for a growing or declining population) over a multi-decadal lifespan. In addition to disinfection methods using chlorine, ozone, or ultraviolet light (UV), novel disinfection methods might include induction of autolysis of bacteria in water systems, for instance using quorum-sensing particles or bacteriophages. Limiting the formation of DBPs was recognized as a driver for this subtheme ( Li and Mitch, 2018 ). While new approaches are constantly under development, consideration of the health impacts of pathogen reduction by various methods and degrees would help to support decision-making. The extension of the SDGs to serve all, including remote populations in unique environments, requires added attention to water treatment decentralization and conservation via onsite reuse ( Insight et al., 2017 ).

Water microbiology

Water microbiology research concerns microbial communities and their effects on water resources and human or animal health. Microbes can float freely in water, attach to particles, aerosolize, or live in biofilms (slimy matrices that form on surfaces). Knowledge about pathogenic microorganisms in water and wastewater has saved millions of lives over the last century from enteric disease outbreaks such as cholera ( Rosen, 2015 ; Schlipköter and Flahault, 2010 ) and typhoid. The drinking water microbiome may comprise up to 40 phyla, which change during various stages of water treatment and distribution ( Proctor and Hammes, 2015 ). The primary global burden of disease is associated with enteric pathogens spread via water and food, particularly rotavirus, Cryptosporidium, Shigella, and Enterotoxigenic Escherichia coli (ETEC) ( Kotloff, 2017 ). Microbes and their pathogenicity are constantly evolving in response to environmental stimuli, which can lead to antimicrobial resistance and emerging human diseases. Topics raised by participants included interaction within microbiomes and biofilms, community stability or regrowth (e.g., in distributed or stored water), and investigative tools such as metagenomics.

Among biological hazards to human health, water treatment processes have traditionally targeted enteric pathogens only ( Fewtrell and Bartram, 2001 ) and these continue to be critical for safety ( Setty et al., 2018a ). More recently, disease outbreaks associated with treated water and other water systems, such as cooling towers, show a significant increase in respiratory diseases caused by water-based opportunistic pathogens such as Legionella pneumophila ( Beer et al., 2015 ; Gargano et al., 2017 ). Effective and safe drinking water distribution systems and plumbing systems in large buildings ( Cunliffe et al., 2011 ) are crucial to protect and improve health. Water treatment processes, nutrients, disinfection residuals, DBPs, and the abiotic factors of distribution systems and on-premises plumbing (e.g., stagnation of water, temperature) have significant impacts on the microbial community of tap water and associated water quality ( Wang et al., 2018 ). Moreover, free-living amoebae and some other protozoa present in distribution systems protect certain bacterial pathogens from disinfectants and support intracellular growth of pathogens like Legionella ( Balczun and Scheid, 2017 ; Lu et al., 2014 ; Pagnier et al., 2015 ).

Microbial quality and chemical quality interact, especially where chemical disinfectants used for microbial inactivation give rise to added chemical hazards. One primary concern has been the health effects of DBPs, since many are considered carcinogenic ( Richardson et al., 2007 ). Some suggest adapting treatment processes to select for bacteria such as Rhodococcus and Mycobacterium , which are capable of biodegrading DBPs ( Sharp et al., 2010 ; Gerrity et al., 2018 ). Yet, another concern is inadvertent selection of disinfectant-resistant bacteria such as mycobacteria or antimicrobial resistant bacteria that can opportunistically cause infection in immunocompromised people ( Von Reyn et al., 1994 ; Whiley et al., 2012 ; Gerrity et al., 2018 ; Liu et al., 2018 ; Potgieter et al., 2018 ; Stüken et al., 2018 ). Thus, manipulation of microbial ecology to promote “beneficial” microbes is an important area of continuing research.

Advancement in gene sequencing methods provide exciting new insights and opportunities for water microbiology research, although the presence of nucleic acids does not translate directly to infectivity ( Tan et al., 2015 ). Future research might target biological processes in water treatment, use of metagenomics to characterize occurrence and fate of antimicrobial resistance genes, the virome of wastewater, or microbial ecology. Understanding microbial ecology is important to design sustainable and safe water systems. Some studies suggest that tap water bacterial composition depends primarily on treatment processes rather than source water ( Wang et al., 2013 ; Zhang et al., 2017 ). Thus, the microorganisms and DBPs present in treated drinking water could alter the microbiota in the human gut, which would ultimately influence human health (e.g., Von Hertzen et al., 2007 ). A better understanding these relationships could inform the best drinking water management approaches for achieving public health benefits.

Risk assessment and management

Risk assessment and management consists of technologies, methods, behaviors, and processes that support conversion of evidence about risk to planning and mitigation among stakeholders. This often involves ranking different hazards harmful to people at different life stages, taking into account mortality, illness (disability-adjusted life years or DALYs), and other types of consequences. Subthemes of participant contributions on this topic included: (a) management tools for combining multiple types or measures of risk under a common framework, (b) risks related to extreme weather events, (c) security in the face of political instability (e.g., war or terror attacks), and (d) accounting for uncertainties and unknown risks. An additional submission related to the water microbiology and information and artificial intelligence categories suggested using burgeoning data availability (e.g., metagenomics and other “omics”) to inform risk management. Changing demographics represented a relevant driver, as this may lead to shifts in the sensitivity or receptivity of populations to various hazards.

Multiple risk management tools and approaches were raised as potential options for water systems, including synthesis frameworks such as Water Safety Plans ( Bartram et al., 2009 ), quantitative microbial risk assessment (QMRA; Petterson and Ashbolt, 2016 ) for microbial pathogens, as low as reasonably achievable (ALARA; Lindhe et al., 2010 ) principles for contaminant reduction, and geospatial modeling (e.g., Lafforgue et al., 2018 ). One issue may be how to combine data-driven management of multiple risk categories (e.g., water quality, financial risk, reputational risk). Risk management programs such as Water Safety Plans have been actively piloted and evaluated in recent years ( WHO and IWA, 2017 ), demonstrating potential benefits to public health ( Gunnarsdóttir, et al., 2012 ; Setty et al., 2017 ), but work remains to facilitate an enabling implementation environment in both low-middle and high-income countries ( Baum and Bartram, 2018 ). While most efforts in past decades were dedicated to managing chemical hazards, emerging risks are more often linked to microorganisms ( Rusin et al., 1997 ). Based on prior seminar topics, risk assessment related to nanotechnology is needed as compounds may be more or less toxic at the nanoscale ( Rocha-Santos, 2018 ). Climate extremes are expected to become more severe in coming decades ( IPCC, 2014 ), leading to a great deal of research among water suppliers, environmental managers, and public health officers around mechanisms for planning, adaptation, and resilience ( Deere, 2017 ).

Regarding security, the terrorist attacks on September 11, 2001 led to greater awareness around water supply vulnerabilities ( Camarillo et al., 2014 ). Safety largely requires responsiveness to both urgent and subtle water crises, including those with non-malevolent causes such as long-term drought or shifting water demands. In the NGT exercise, hospitals were mentioned as a particularly vulnerable type of institution, mirroring newer findings of poor attention to water, sanitation, and hygiene systems in settings with greater-than-average immunocompromised populations at risk of infectious diseases ( WHO & UNICEF, 2015 ). Loss of hospital water supplies (e.g., due to a crisis or intermittent service) puts patients at greater risk and often requires compromises in sanitary procedures or physiologically stressful patient transfers. Approach and methodology options for addressing uncertainty and unknown risks include the precautionary principle, expert consultation, probabilistic inference, sensitivity tests, fuzzy-set theory, value-based weighting preferences, or conditional rules ( Almaarofi et al., 2017 ; Dominguez-Chicas and Scrimshaw, 2010 ; Petterson and Ashbolt, 2016 ). Automated data production, management, and decision-support systems may aid in earlier detection of risks, enabling faster response times.

Sanitation considers management of human excreta, wastewater, and solid waste to lessen negative human, animal, and environmental consequences. Within this area, key subthemes raised by participants included access to sanitation services and improving their quality, especially using decentralized wastewater treatment systems (DEWATS). Priorities also included improving knowledge of pathogens and micropollutants in liquid and solid waste disposal, particularly for risks associated with their persistence, removal from wastewater, and the sanitary, environmental, and occupational implications. In sum, these topics complement the water resources and socioeconomic subthemes, and create synergies for enhancing usability of freshwater and marine resources.

Ensuring availability and improvement of sanitation systems has been an area of intense activity. The WHO and United Nations Children’s Fund (UNICEF) Joint Monitoring Programme for Water Supply, Sanitation and Hygiene (JMP) reported that more than 2.1 billion people gained access to improved sanitation between 1990 and 2015 ( WHO and UNICEF, 2017 ). Still, more than 2.4 billion people had no access to improved sanitation and 1 billion remained without any sanitation system. Taking into account the ambitious new service norm of “safely managed” sanitation, meaning a household has an improved facility with in-situ excreta disposal or transport and treatment offsite, a whopping 5.3 billion people lacked coverage ( WHO and UNICEF, 2017 ). Decentralization appears as a logical evolution for handling increasing loads of wastewater and urban stormwater. A study published by the Organisation for Economic Co-operation and Development (OECD) demonstrated the potential for sustainable decentralized water resource management in urban environments, with better flexibility and at a lower cost than current sanitation systems ( OECD, 2015 ). In addition, many urban centers continue to seek solutions for managing concentrated urban runoff, in some cases by facilitating treatment of discharge collected by separate or combined sewer systems ( Barbosa et al., 2012 ).

Better knowledge of the fate of pathogens and micropollutants from wastewater represents a valuable addition to the research docket, as it will improve understanding and management of subsequent risks to public health ( Campos et al., 2016 ; Gavrilescu et al., 2015 ). Along with molecular and chromatographic methods, high-throughput sequencing and mass spectrometry have enabled more rapid analysis of their transport, dissemination, and persistence in the environment. Still, researchers have limited information on both the long-term effects of micropollutant cocktails and their relationship with the emergence of new bacterial and viral pathogens ( Jekel et al., 2013 ; Sano et al., 2016 ). Concerning the implications of waste disposal, some studies have addressed wastewater reuse and solid waste disposal ( Kellis et al., 2013 ; Kinnaman, 2017 ; Maimon et al., 2010 ), but more attention is needed to determine method effectiveness and pollutant persistence. Seminar participants felt that wastewater reusability (e.g., for water, energy, nutrients) and mastery of pollutant removal were critical components of waste management for the next 5–10 years. Forward-looking commentary on adaptations and the potential use of wastewater revolved around public health surveillance via human biomonitoring ( Joas et al., 2017 ).

Water resources

Water resources refers to conservation of existing and potential new ambient water supplies for human and ecological use. Research priorities primarily fell into two subthemes: (a) water supply quantity and quality stressors and (b) water management solutions. Quantity stressors included shortage, drought, and water loss. Quality stressors related to industrial, agricultural, and other pollutant sources that lead to groundwater contamination and fecal pollution in watersheds. Regarding management solutions, participants cited protection, conservation, improved management planning at the watershed level, and attention to irrigation practices. To achieve SDG 6, the 2018 United Nations’ world water development report emphasizes nature-based solutions tapping wastewater as an underused resource ( WWAP/UN-Water, 2018 ), consistent with the sanitation theme above.

Water resources planning and accounting will require projection of suspected stressors, such as climate change ( Olmstead, 2014 ). Accounting concepts include a water footprint, defined as the total volume of freshwater used directly and indirectly by a nation or a company, or in the provision of a product or service ( Chenoweth et al., 2014 ). Economic approaches such as payment for environmental services (PES) represents a potential option to protect water quality at the watershed scale ( Lafforgue, 2016 ). Bioremediation and source tracking methods were similarly raised as management tools to address pollutant fate and movement within surface and groundwater. Overlapping with the water reuse category, an additional submission had to do with considering the circular economy of water resources in which uncontaminated water circulates in closed loops, allowing repeated use ( Eneng et al., 2018 ) rather than traditional collection, use, and disposal into the environment.

Information and artificial intelligence

This category revolves around data collection and processing to enable EIDM. Few submissions were repetitive or demonstrative of trends, suggesting a wide array of needs in this research area. Data modeling was a research need for holistically considering contaminant sources, pathways, effects on water quality, and control options at a systems level inclusive of the watershed, infrastructure, and receptors (e.g., Lafforgue et al, 2018 ). Other needs included management, transmission, integration, and safe storage of large amounts of data from diverse sources (e.g., watershed, water supply and treatment, public health, open data, video streams, social media). Appropriate instrumentation and centralized management systems should be developed to accomplish these tasks. Speed was of key concern, for example using artificial intelligence as an alternative to long, difficult, and costly epidemiology studies.

Experts recognize care should be taken in communicating the potential for artificial intelligence to replace existing methods. For instance, Google Flu Trends ( Ginsberg, 2009 ) was released in 2006, but withdrawn after a few years due to its tendency to over-predict influenza infections based on Google search data. Despite some limitations, data analytics and artificial intelligence will be considered useful and necessary tools to explore data and contribute to better management of water systems in the future. Participants recommended data systems both to survey ongoing performance shifts and to detect or diagnose abnormalities (e.g., in infrastructure integrity). Optimization exercises can help to solve complex water network design or health hazard problems, taking into account many different criteria, and leading to better solutions than manual design (e.g., Maier et al., 2014 ).

Real-time/rapid methods

Real-time monitoring of drinking water systems includes the technologies and data systems that help managers to maintain safety and respond quickly to accidental or malevolent incidents. Participant feedback dealt with early, real-time, online, and point-of-use contaminant detection, spanning both chemical and biological parameters. In addition to informing water treatment processes, participants anticipated deployment of sensors in source water, distribution systems, and at the point of use to maintain active surveillance and problem detection.

Research interest has been growing in online monitoring for both chemical and biological water quality, including harmful algal bloom (HAB) toxins ( Storey et al. 2011 ; Lopez-Roldan et al. 2013 ). Online monitoring equipment can be installed as an early warning system for the water intake, treatment process monitoring and main entry points to the distribution system. In ambient waters, real-time and rapid methods also concern water-contact and other recreational uses. Complexity derives from the current impossibility of constructing a single sensor to detect all contaminants or pathogens. Studies investigating the performance of various water quality sensors on different contamination patterns suggest monitoring changes to conventional parameters, such as pH, temperature, turbidity, electrical conductivity, and free chlorine concentration, may sufficiently address concerns associated with health risk, customer perceptions (aesthetic taste and odor), and asset management ( Hall et al. 2007 ).

Such monitoring systems should distinguish abnormal changes from normal variations. Thus, event detection models are required for exploring the time series of each water quality parameter and detecting anomalies in water supply systems and networks ( Housh & Ostfeld 2015 ). The cost for sensor deployment and operation limits the number of locations that can be monitored in real time. Future studies will likely aim to develop low-cost and miniaturized sensor technologies to make continuous and complete monitoring possible throughout a water system. In addition to treatment facilities, participants raised installing sensors in distribution pipes (such as sensor chips attached to pipe walls), consumer taps, and individual water meters.

Water reuse

Water reuse refers to safe reuse and recycling to enable sustainable water supplies for human and ecological use. Increasing water supply challenges, aggravated by human population growth and climate change, have driven interest in water reuse as a main component of the new era of water management ( Hering et al., 2013 ). Within this area, key subthemes raised by participants included: technologies for the treatment and reuse of wastewater or alternative water sources, health risks associated with water reuse in particular for potable purpose, and public perception and acceptance of water reuse for potable and non-potable (e.g., agriculture, industry, toilet flushing) purposes.

Research into engineered treatment technologies has been intense, including membrane filtration and oxidation treatment to eliminate microbial and chemical contaminants ( Tang et al., 2018 ; Zodrow et al. 2017 ). Recent advances in membrane technology, particularly reverse osmosis (RO), have played a key role in producing highly purified recycled water and driving an increase in water reuse projects worldwide. This research aims to achieve cost-effectiveness and reliability in removing microbial and chemical contaminants ( Tang et al., 2018 ). Since some chemical contaminants (e.g., certain DBPs, pharmaceuticals) can cross RO membranes, post-RO oxidation treatments capable of removing these contaminants have been integrated into treatment schemes. Traditionally, advanced oxidation processes that generate hydroxyl radicals have been used, and electrochemistry-based oxidation treatment has been attracting increasing attention ( Feng et al., 2016 ). The degree of adoption of any technology will depend on its effectiveness, energy demands, feasibilty, and integration into future water treatment systems ( von Gunten, 2018 ). Nature-based solutions such as managed aquifer recharge (MAR) and biofiltration similarly show promise for promoting water reuse ( Water JPI, 2016 ).

To enhance understanding around the safety of water reuse, further toxicological and epidemiological studies are warranted ( NRC, 2012 ). In exposure circumstances where toxicological and epidemiological dose-response data are lacking, risk assessment can account for uncertainty and use the best available knowledge to support design of safe reuse systems ( NRC, 2012 ). Further, quality assurance of treatment schemes with regard to elimination of chemical and biological contaminants, economic effectiveness, and feasibility of integration into water systems must be resolved to demonstrate usefulness of novel treatment approaches, for example via studying the scaled-up engineering designs ( Lazarova et al, 2013 ). Water reuse may be an especially efficient option in water-scarce contexts, where regulation permits reuse and other options cost more ( Lafforgue and Lenouvel, 2015 ).

In sum, water reuse complements other efforts to increase water availability (e.g., conservation, desalination) and appears as a critical component of ongoing sustainable water management. Some participants mentioned public perception of water reuse, which overlaps with the socioeconomy of water. Public acceptance of water reuse is a prominent factor in determining the future of water reuse, as it significantly influences political decisions on water reuse projects ( Dolnicar et al., 2011 ).

Water-energy nexus

The water-energy nexus refers to the study of how energy use interacts with provision of sustainable water services. Within this area, key subthemes raised by participants included resource rarefaction (water, energy, raw materials) and how to counteract this phenomenon by developing synergies between water-energy-waste cycles, redefining water and sanitation using decentralized and renewable energy-based solutions, safe water treatment at a low energy cost, and microbial fuel cells for sustainable energy production.

Water rarefaction is increasing due to long-term increases in water abstraction, declining resource availability ( Damania et al., 2017 ; 2030 Water Resources Group, 2009 ), and the projected effects of climate change. Research focuses on three main options: increasing water production by desalination, reducing abstraction by recycling urban waters, and reducing water consumption and water losses. However, desalination and water recycling frequently use energy-intensive membrane filtration, replacing a problem by another one. Singapore, for example, is an island city-state faced with this issue ( Lenouvel et al., 2014 ). An integrated perspective would account for such risk substitution.

For instance, the Water and Wastewater Companies for Climate Mitigation (WaCCLIM) roadmap to carbon neutrality in urban water recommends research into low-energy options to produce, transfer and purify water ( Ballard et al., 2018 ). One option is to recover or produce energy from water (e.g., hot water recycling, energy-neutral wastewater treatment, hydropower production in water networks, microbial fuel cells). Another option is to save energy (e.g., low-energy membrane filtration, pumping and pressure optimization, reduction of water consumption, early leak detection). Water recycling in short loops using nature-based solutions may improve water management and save energy ( WWAP/UN-Water, 2018 ; Lafforgue and Lenouvel, 2015 ; Kavvada et al., 2016 ). OSMOSUN® solar desalination units are one example of a technology combining renewable energy and water production. Similar recommendations are included in the International Water Association Principles for Water-Wise Cities being adopted around the world ( IWA, 2016 ).

In sum, NGT participants felt that water-energy synergies, water short loops, and renewable energy emerged as prominent options to investigate resource rarefaction. Flexible solutions require time and development, as they are very context dependent ( Lafforgue et al., 2014 ). Investigative tools for structuring and testing potential water-energy option combinations (e.g., Urb’Advanced) may be useful.

Comparison to other studies

With increased activity around the SDGs, WaSH professionals have renewed efforts to examine high-priority research areas ( UN Water, 2018 ; WHO and UNICEF, 2017 ). Needs assessments are a valuable step in structuring research, policy, and practice responses. This study is one of several efforts to gather data on water and health knowledge needs, for instance via literature review ( Hutton and Chase, 2016 ), electronic survey ( Setty et al., 2018b ), review of meeting abstracts ( Kogevinas, 2017 ), and knowledge translation activities ( USAID, 2017 ). While the framing differs among agenda-setting methods and studies, these synergistic efforts contribute to capacity building to support global goals toward safe water and sanitation for all.

In connection with WHO-Europe efforts to set priorities for environmental health research, Kogevinas (2017) recommended dialogue between researchers and stakeholders rather than algorithms or semi-quantitative grading to non-prescriptively assess potential research topics against novelty, importance to people, impact on policy, and technical innovation and development. The WaSH research prioritization survey in collaboration with the Sanitation and Water for All partnership ( Setty et al., 2018b ) was structured around SDG 6 targets, with heavy representation from African partners, whereas the present effort garnered representation primarily from high-income regions. The literature review ( Hutton and Chase, 2016 ) looked retrospectively at peer-reviewed and gray literature, in contrast to the forward-looking expert elicitation used here. Both the literature review, which is subject to publication bias, and our in-person approach, requiring costly travel, likely underrepresent researchers from lowand middle-income countries.

While the results of these studies overlap in many ways, research policy and the financing of research were not considered in this study. Similarly, while hygiene and associated behavior change were not excluded topics, they did not emerge as a substantive focus during the NGT exercises. Though not explicitly discussed during the NGT sessions, the context for the study was set in an era of shifting priorities, as the SDGs set out more challenging expectations for water and health professionals, and unlike similar development initiatives in preceding decades, the SDGs explicitly apply to countries at all stages of development. The targets for SDG 6 ( UN, 2018 ) comprise:

• Achieve universal and equitable access to safe and affordable drinking water for all
• Achieve access to adequate and equitable sanitation and hygiene for all and end open defecation, paying special attention to the needs of women and girls and those in vulnerable situations
• Improve water quality by reducing pollution, eliminating dumping and minimizing release of hazardous chemicals and materials, halving the proportion of untreated wastewater and substantially increasing recycling and safe reuse globally
• Substantially increase water-use efficiency across all sectors and ensure sustainable withdrawals and supply of freshwater to address water scarcity and substantially reduce the number of people suffering from water scarcity
• Implement integrated water resources management at all levels, including through transboundary cooperation as appropriate
• Protect and restore water-related ecosystems, including mountains, forests, wetlands, rivers, aquifers and lakes
• Expand international cooperation and capacity-building support to developing countries in water- and sanitation-related activities and programs, including water harvesting, desalination, water efficiency, wastewater treatment, recycling and reuse technologies
• Support and strengthen the participation of local communities in improving water and sanitation management

Equity represents a central component of SDG 6 and also appeared as an underlying driver of research needs in this study. Many aspects of SDG 6, such as “safe,” “affordable,” and “participation” were mentioned using similar wording under the socioeconomy of water category, which dominated the research priorities; however, subthemes addressed neither transboundary management nor capacity building. Untreated wastewater management features in both the SDG 6 targets and the sanitation category of the research priorities, although the SDG 6 focus on ending open defecation was reflected as increasing access to sanitation. The water resources and water reuse categories corresponded well to the SDG 6 targets, including remediation of polluted ecosystems and desalination, respectively. The research agenda presented here paid less heed to the specific needs of women and girls (e.g., for physical safety and menstrual hygiene management).

Limitations

The NGT approach was appropriate for including all ideas (rather than just the majority), accommodating heterogeneity of experience in the group, and ensuring equal footing for underrepresented voices in research planning ( CDC, 2006 ; Tague, 2004 ). Although the results provided sufficient information for the study’s purposes and saturation was achieved via subsequent data triangulation, limitations to internal validity include adaptations of the process used to fit time constraints. Limitations of NGT include the need for conformity within a somewhat mechanical process. The group sizes (33 or 18 participants) were large by NGT standards ( Taylor et al., 1958 ). While unlikely to have restricted idea generation, this might have hampered full-group discussion and clustering of ideas. We sought to overcome this by more thoroughly reviewing the categorization afterward, using multiple reviewers. Normally, NGT includes scoring and ranking after grouping ( CDC, 2006 ), but we accomplished this afterward using simple frequencies and requested member checking remotely several months following the sessions.

While an effort was made to consider ten years of data and multiple categories of water and health professionals, the methods inherently rely on a sample of professionals, which limits external validity and generalizability. As is the case with focus groups, the viewpoints captured may not represent all members of a certain demographic. Since participants need to travel to attend the conference in person, representation skewed toward a small number of high-income countries especially in vicinity of France. Furthermore, the scientific committee and practitioners were invited, and this method of “sampling” is more likely to result in a cohesive group that shares similar viewpoints. The student participants, in contrast, can openly apply to attend, and are intentionally selected to increase diversity. Water and health topics specified on the event announcement aim to attract student expertise in the area of emerging waterborne pollutants and pathogens, epidemiology, microbiology, toxicology, analytical chemistry, risk assessment, water treatment, water hygiene, public health, and sociological aspects of risk management. Advertisement and marketing is generally limited and likely does not reach all possible candidates.

Recommendations

Research planning processes often stem from independent primary investigators, either in isolation or in collaboration with others, typically with a goal of achieving publication in a peer-reviewed journal. In many cases, research planning and execution is closely determined by funding availability on specific topics, for example via requests for proposals ( Setty et al., 2018b ). Mechanisms for accountability to the public, governments, and practitioners are less well established in academia, although applied, translational, and implementation research has gained traction in recent decades ( Hering, 2018 ). Setty et al. (2018b) found stakeholders outside of academia (e.g., governmental and civil society organizations) sought but perceived fewer opportunities to engage in learning and training events. Making research relevant to potential end users and decision makers recommends cross-sector communication about research priorities ( Kogevinas, 2017 ; Roux et al., 2006 ). Although not inclusive of all possible stakeholder types, this project offered one approach to eliciting practitioner and potentially other stakeholder group perspectives on research planning.

Broad, inclusive processes are recommended for research planning ( Setty et al., 2018b ), including scientists as well as other stakeholder types, with attention to underrepresented voices. Such processes are more likely to identify a mix of short- and long-term priorities as well as diverse perspectives and needs. The SDG process, for instance, provide an example of inclusive priority setting, which can be used to justify research efforts from 2016–2030 ( UN General Assembly, 2015 ). Another example comes from the US National Science Foundation’s Advisory Committee for Environmental Research and Education in 2018, which invited input from members of the Association of Environmental Engineering and Science Professors, an international group of professors educating on environmental protection, science, and technology topics ( NSF, 2018 ). They sought to identify environmental research and education directions that would further advance national security and economic competitiveness. This direct solicitation took place in tandem with a public comment period over about two months.

Conscientious, structured exercises such as NGT can bolster equity, transparency, and inclusivity of research planning processes ( Viergever et al., 2010 ). This and other approaches may be adapted to fit case-specific constraints and needs, although users should document adaptations to consider how they might alter effectiveness ( Allen et al., 2017 ; Bartunek and Murninghan, 1984 ). Depending on organizational needs, periodic reflective exercises can be timed to fit into research planning cycles ( Weichselgartner and Kasperson, 2010 ). In practical terms, participation in research prioritization exercises can be time-consuming. At a macro level, doing an exercise in conjunction with an existing collaborative event created minimal additional cost and labor. At a micro level, grouping similar responses together as they came up likewise offered a time advantage.

Conclusions

High-priority research areas (in order of frequency) included the socioeconomy of water, water quality, water treatment, microbiology, risk assessment and management, sanitation, water resources, real-time and rapid methods, water reuse, and the water-energy nexus. Each of these themes housed a range of more detailed research subthemes and questions. Underlying drivers of water and health research included social inequity, shifting international relations, demographic trends, aging infrastructure, antimicrobial resistance, and emerging diseases. To support attainment of the SDG targets for water and sanitation, water and health professionals will need to integrate efforts across environmental and health systems, sectors, and exposures; decentralize infrastructure and monitoring capabilities; and adopt more advanced processes for safety, surveillance, and responsiveness. The study methods and findings may prove useful for planning research funding offerings, projects, practicums, and quality improvement efforts among a variety of organizational types focused on water and health issues.

• Expert elicitation technique ranked water and health research priorities.
• A prime concern centered on the socioeconomics of meeting water needs.
• Team-based narrative review provided commentary on all research priorities.
• Dialogue among scientists and practitioners is needed to progress toward SDGs.

Acknowledgements

Our gratitude extends to all participants in the 2018 International Water and Health Seminar in Cannes for their enthusiastic collaboration. We are especially indebted to the meeting coordinators for arranging the session logistics. Suez provided financial sponsorship for the meeting, and student travel was in many cases made possible by their respective sponsors and institutions. Additional financial support for research (KS) was provided by the US National Institute of Environmental Health Sciences (grant T32ES007018), and the University of North Carolina at Chapel Hill Royster Society of Fellows.

Declaration of interest

Authors include employees and contractors of Suez, who received remuneration for their time and travel expenses to attend work functions such as the seminar where this study took place. Senior academics on the scientific committee were similarly reimbursed for travel expenses to attend the seminar. Students accepted to the seminar received accommodations and meals for the duration of the seminar. Some participant institutions have received separate funding from Suez for specific research projects.

Workshop participants

Jamie Bartram, The Water Institute at UNC

Elke Dopp, IWW Water Center

Martin Exner, University of Bonn

Philippe Hartemann, University of Lorraine

Paul Hunter, University of East Anglia

Gertjan Medema, KWR Water Cycle Research Institute

Mark Wiesner, Duke University

Michael Wilhelm, Ruhr-University Bochum

Practitioners

Reynald Bonnard, Suez

Sophie Courtois, Suez

Jerome Enault, Suez

Michel Lafforgue, Suez Consulting

Xavier Litrico, Suez

Jean-François Loret, Suez

Pierre Pieronne, Suez

Olivier Schlosser, Suez

Daniel Villessot, Suez

Flavia Zraick, Suez

Claire Bertelli, University of Lausanne*

Helena Bielak, IWW Water Center

Nadratun Chowdhury, Duke University

Christina Fiedler, University of Natural Resources and Life Sciences, Vienna

Charlotte Christiane Hammer, University of East Anglia

Tarek Manasfi, University of Aix-Marseille*

Manon Michaut, University of Rouen

Laura Palli, University of Florence

Yoann Perrin, University of Poitiers

Nicholas Rogers, Duke University

Sydney Rudko, University of Alberta

Mohamed Shaheen, University of Alberta

Sohan Shrestha, University of Queensland

Esther Sib, University of Bonn

Vincent Tesson, French National Institute for Agricultural Research

* postdoctoral scholar

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As the world’s largest multilateral source of financing for water in developing countries, the World Bank is committed to Water for People and Planet.

Water touches every aspect of development and it links with nearly every Sustainable Development Goal (SDG). It drives economic growth, supports healthy ecosystems, and is essential and fundamental for life itself.

Approximately 2 billion people around the world do not have safely managed drinking water services, 3.6 billion people do not have safely managed sanitation services, and 2.3 billion lack basic handwashing facilities. Gaps in access to water supply and sanitation, growing populations, more water-intensive patterns of growth, increasing rainfall variability, and pollution are combining in many places to make water one of the greatest risks to economic progress, poverty eradication and sustainable development.

The consequences of such stress are local, national, transboundary, regional, and global in today’s interconnected and rapidly changing world. Consequences will be disproportionately felt by the poorest and most vulnerable. Climate change expresses itself through water .  Nine out of ten natural disasters are water-related. Water-related climate risks cascade through food, energy, urban and environmental systems. If we are to achieve climate and development goals, water must be at the core of adaptation strategies.

To guide effective climate change adaptation, activities should reflect the importance of water management for reducing vulnerability and building climate resilience, prioritizing the following actions:

• Expand beyond traditional integrated water resources management (IWRM). Efforts to reduce greenhouse gas emissions also depend on access to reliable water resources, as all mitigation actions need water to succeed.
• Promote investment and solutions that incorporate management of " natural infrastructure"  – the ecosystem services provided by healthy watersheds and coasts – and their benefits for climate-resilient development of the food and energy sectors.
• Support actions at scale to build climate resilience by combining watershed management, sustainable infrastructure, and empowerment and learning through adaptive institutions.

Economic growth is a "thirsty business . "  Water is a vital factor of production, so diminishing water supplies translates into slower growth. Some regions could see their growth rates decline by as much as 6 percent of GDP by 2050 as a result of water-related losses in agriculture, health, income and prosperity. Ensuring a sufficient and constant supply of water under increasing scarcity is essential to achieving global poverty alleviation goals.

• Optimizing the use of water through better planning and incentives will help to improve welfare and increase economic growth. Economic instruments such as water permits and prices, if well implemented and enforced, can improve stewardship of water resources.
• Expanding water supply and availability where and if appropriate is vital. This includes investments in water storage, water reuse and recycling and, where viable, desalinization. These interventions must be accompanied by policies to promote water efficiency and improve water allocation.
• “Water proofing” economies to limit the impact of extremes and uncertainties is also among the top priorities. Better urban planning, expanding crop insurance to protect farmers, and citizen engagement will build resilience and minimize economic impacts of adverse events.

Water  is crucial in determining whether the world will achieve the SDGs. The world needs a fundamental shift in how it  understands, values and manages water.

• Understanding Water  means making evidence-based decisions about water using strengthened water data.
• Valuing Water  means recognizing the values that societies accord to water and its uses, taking these into account in political and business decisions including decisions about appropriately pricing water and sanitation services.
• Manage Water  means pursuing integrated approaches to water resource management across local, national, and regional levels.

Water is essential for inclusive growth.  Water belongs to everyone, yet many are excluded from its benefits. Ensuring that water is equitably and sustainably shared requires an inclusive approach. Women, youth, persons with disabilities, indigenous groups and other underrepresented and marginalized groups need access and voice in the water sector. The factors driving exclusion of these groups are increasing: it is estimated that climate change will force over 140 million people to migrate within their countries by 2050.

In water and sanitation utilities, fewer than one in five workers are women, and in the broader water sector, fewer than one in four engineers or managers are women. Increasing women’s participation at all levels of the water sector benefits women, the community, and organizations.  

​Around the world, about 500 million women, girls, and other menstruators struggle to access menstrual products or safe, private, hygienic spaces in which to use them. Lack of affordability or accessibility, along with the stigma associated with menstruation in many societies, has wide-ranging negative effects, severely limiting participation in public life.

​​Water knows no borders.  Transboundary cooperation is needed to share this vital resource, which is vital for the economic well-being of entire regions. More than three billion people rely on transboundary river basins for their needs, yet 60 percent of the world’s 310 international river basins lack frameworks to govern disputes. Climate and pollution risks in many transboundary basins, already high, are expected to increase.  

​The Bank works with clients to build strong institutions, dialogue processes, and information systems that can support transboundary resource management. Given the increasing pressure on common water supply sources, developing cooperative agreements will benefit everyone.

Smart investments in clean water and sanitation  prevent needless deaths and transforms lives. Healthier children become healthier adults who contribute more to the economy. This principle is at the core of the World Bank’s Human Capital Project.

Sanitation is critical to health, economic growth and the environment. Investing in sanitation is about safeguarding human health, investing in people and transforming lives. Approximately  446,000 children under 5 years die due to diarrhea  linked to inadequate WASH. This amounts to 9% of the 5.8 million deaths of children younger than 5. 

​​Safely managed water, sanitation, and hygiene (WASH) services are also an essential part of preventing and protecting human health during infectious disease outbreaks, including the recent COVID-19 pandemic. According to a WHO/UNICEF technical brief on WASH and waste management for COVID-19: “Frequent and proper hand hygiene is one of the most important measures that can be used to prevent infection with the COVID-19 virus. WASH services should enable more frequent and regular hand hygiene by improving facilities and using proven behavior change techniques.”  These efforts also help prevent other deadly infectious diseases, including cholera, dysentery, hepatitis A, and typhoid.

Political commitment and leadership, technological innovations, and breakthroughs in service delivery and financing models are all needed to support governments to deliver on their commitment to SDG 6.2 – achieving access to adequate and equitable sanitation and hygiene for all by 2030.

Learn more about the different business lines of the water sector in these infographics: 

View the water supply and sanitation infographic>>, view the water resource management infographic>>, view the water in agriculture infographic>>, view the dam safety infographic>>, view the social inclusion infographic>>, view the climate change and water infographic>>.

Last Updated: Jul 28, 2023

In response to the water and sanitation crisis, the World Bank Water Global Practice (Water GP) is committed to Water for People and Planet . The SDGs provide an opportunity for the World Bank Group and development partners to work together in support of this vision.

And, in 2019, the Water GP launched its new Strategic Action Plan. Our vision remains a Water Secure World for All, to be delivered through three inter-related pillars: (1)  sustain water resources , (2)  deliver services , and (3)  build resilience . The World Bank has played a key role in driving delivery when it comes to the SDGs. We continue to implement programs and projects across the world, convene a wide range of actors to achieve cross-sectoral solutions, and share our data, knowledge and know-how with others in service of a water-secure world for all .

With a portfolio of water investments of almost US$30 billion and a staff of hundreds of water experts across the world, the Water GP is uniquely positioned to address these themes, developing and sharing global knowledge while amplifying the impact of lending through technical assistance on the ground.

The World Bank has identified five priority themes to achieve the Sustainable Development Goal in the water sector (SDG 6). To address the challenges of increasing water scarcity and variability and to ensure that results are maintained in the future, a renewed focus on the multiple facets of resilience and sustainability is needed. However, without new efforts to improve inclusion , many will still be unable to reap the benefits of water and will be disproportionately impacted by water-related disasters.

Helping countries achieve greater sustainability and inclusion in the water sector requires investment in institutions , to complement the traditional focus on building infrastructure. Building the institutions and infrastructure needed for universal access and more sustainable water management practices also demands a vast increase in financing for the water sector, which can only be achieved by improving financial viability and leveraging donor funding to tap other sources of finance.

These five priority themes form the core of a partnership for a water-secure world, supported by the Global Water Security & Sanitation Partnership (GWSP) . This is a Multi-Donor Trust Fund, launched in 2017 that enables the Water GP to address the five themes across its global portfolio.

To more effectively bring critical resources to the front lines, the GWSP has been designed as a Water GP core asset—its “think-tank”—which expands and deepens the impact of its lending program.

In 2018, the 2030 Water Resources Group (2030 WRG)   — a public-private-civil society partnership — became part of the Water GP family. 2030 WRG supports government-accelerated reforms with the aim of ensuring sustainable water resources management for long-term development and economic growth.

To respond to COVID-19, action in the WASH sector is critical for both containing the virus and lowering its immediate impact and aftermath. Three priority areas are identified as part of the emergency response:

Emergency support to secure and extend water and sanitation service provision, including:

• Support to water supply and sanitation (WSS) service providers to prepare emergency plans and ensure continuity of service delivery through inter alia: provision of water treatment chemicals and spare parts, availability of fuel for pumps and treatment, maintaining staffing levels, providing protective equipment for utility staff and salary supplements to compensate for the additional work-loads.

Last Updated: Oct 03, 2022

In FY16-18, the World Bank contributed to providing more than 47 million people with access to an improved water source and provided more than 24 million people with access to improved sanitation facilities. Below are some specific results from the World Bank-supported projects in countries.

India: Andhra Pradesh and Telangana State Community Based Management

The World Bank-supported Andhra Pradesh and Telangana State Community Based Management (APCBTM) project in India benefitted 605,052 people by strengthening the capac­ity of community-based institutions. The project developed and equipped 116,164 hectares (ha) of land with irrigation and drain­age services. In addition, the project developed and rehabilitated tank irrigation infrastructure, supported farmers to improve their productivity, and increased cropping intensity by over 30%.

China: Water Conservation Project II

The Water Conservation Project II tackled water scarcity issues through a series of interlinked operations in the Chinese prov­inces of Hebei, Shanxi, and Ningxia – three of the most wa­ter-scarce provinces in the Northern region of the country. To reduce net water consumption, the project reduced water with­drawal for irrigated agriculture in Ningxia and Shanxi Provinces, and groundwater overdraft in Hebei Province. In addition, the project also provided incentives to farmers to lower the agricul­tural production costs and increase the agricultural yield and val­ue in all three of those provinces. Water withdrawal in Ningxia was reduced by 22.67 million cubic meters (MCM) per year; groundwater overdraft in Hebei was reduced by 16.52 MCM per year; groundwater withdrawal in Shanxi was reduced by 5.80 MCM per year. New or improved irrigation and drainage services reached 594,200 beneficiaries, of whom 48 percent are women. Altogether, 290 WUAs in the three provinces have been created or strengthened by the project, comprising over 800 staff and more than 760,000 members (around half are women).

Tajikistan: The Second Public Employment for Sustainable Agriculture and Water Resources Management Project

The Second Public Employment for Sustainable Agriculture and Water Resources Management Project is helping address critical issues in irrigation and water resource management with the overall goal of improving food security for Tajikistan’s most vulnerable communities. Thanks to the project, 6,525 km of an on-farm irrigation network have been manually cleaned, which created income opportunities for almost 24,000 citizens. In addition, irrigation and drainage services have been improved on almost 190,000 ha of arable land. 580 km of secondary and tertiary irrigation canals have been manually cleaned, 44 km of irrigation and drainage canals have been rehabilitated, three major pumping stations have been restored, and riverbank reinforcement works have been completed. Consequently, irrigation has been improved in 920 ha of land.

North Gaza Emergency Sewage Treatment Project

In Gaza , despite the extremely volatile environment, the long-awaited construction of the new North Gaza Wastewater Treatment Plant is now complete and ready for operation, thanks to the World Bank-supported North Gaza Emergency Sewage Treatment  (NGEST) Project. It will provide a long-term, sustainable wastewater management solution for over 400,000 Gazan citizens. The project also helped address the immediate threat to the 52,000 inhabitants living adjacent to the Beit Lahia sewage lakes that flooded the nearby village of Um Al Nasser, killing five, causing countless injuries, and displacing approximately 2,000 people.

Panama: The Metro Water and Sanitation Improvement Project

The Panama Metro Water and Sanitation Improvement Project helped improved the quality of water service for 80,382 beneficiaries in Colón and provided the National Water and Sewer Agency with a replicable model, using performance-based contracts, for effectively piloting and implementing new methods of doing business. The project increased water supply continuity from 13 percent in 2014 to 71 percent in 2017. The quality of service was also significantly improved. The project supported the extension of piped water to 2,115 households and rehabilitated water connections for 12,500 households.

Burkina Faso: The Urban Water Sector Project 

Significant results have been achieved through the IDA financed Urban Water Sector Project (UWSP: 2009–2018): about 700,000 people have gained access to improved water supply; about 440,000 people have gained access to improved sanitation; and about 120,000 students have benefited from improved school sanitation. And the utility’s performance has dramatically improved: ONEA  (Office National de l’Eau et de l’Assainissement), Burkina’s state-owned urban water and sanitation utility, is today  ranked  among the top performing water utilities in Sub-Saharan Africa, with full recovery through revenues of operation and maintenance cost and debt service and partial contribution to capital expenditures, with a staff productivity of 2.9 staff per 1000 connections and a bill collection ratio of 97.7 percent. These achievements, along with the strengthening of the ONEA’s governance, has contributed to paving the way for opportunities to tap into commercial capital and private engagement, for the expansion of needed investments required to respond to increasing water scarcity and fast urbanization.

Last Updated: Oct 06, 2022

benefited with water supply and 690,000 people with sanitation services

FOCUS AREAS

Working together for a water-secure world for all, around the bank group, photo gallery.

STAY CONNECTED

Trust-funded programs.

Global Water Security & Sanitation Partnership (GWSP)

The GWSP supports client governments to achieve the water-related SDGs through innovative global knowledge and country-level support.

2030 Water Resources Group (2030 WRG)

2030 WRG helps countries achieve water security by 2030 by facilitating collective action on water between government, the private sector, and civil society.

Cooperation in International Waters in Africa (CIWA)

The CIWA assists riparian governments in Sub-Saharan Africa in cooperative water resources management and development.

South Asia Water Initiative

The SAWI aims to increase regional cooperation in the management of the major Himalayan river systems in South Asia.

Central Asia Water and Energy Program

The CAWEP builds energy and water security by leveraging enhanced cooperation in all five Central Asian countries plus Afghanistan.

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Research on reclaimed water from the past to the future: a review

• Published: 08 May 2021
• Volume 24 , pages 112–137, ( 2022 )

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• Xun Li 1 &
• Yang Li 1  

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Reclaimed water is an important alternative water supply because it solves the water shortage problem. This manuscript is intended to provide a critical review of recent publications that address future reclaimed water requirements and analyze and visualize historical trends, research hot topics and promising future research directions. The results show that treatment technologies and optimized system designs for reclaimed water were early topics of interest. However, in the current era, "climate change," "sustainability," "technology," "impact" and other keywords appear frequently as the hot topics. Specifically, emerging research topics include (1) the influence of climate change on water quality and water supply system optimization under uncertainty, (2) improving public acceptance and strengthening water management and policy implementation, (3) developing and applying cost-effective treatment technologies for the removal of trace pollutants and (4) more comprehensive health risk assessment and online detection technology. This analysis accurately reflects historical trends in the field and will help researchers choose future research topics.

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A comprehensive review of water quality indices (WQIs): history, models, attempts and perspectives

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Acknowledgements

This work was supported by the National Science Foundation of China [Grant No.51409189]; Training Program for Innovative Research Team in Tianjin Institutions of Higher Education [TD13-5021]; and Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology. The authors also thank the reviewers for their detailed comments.

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Li, X., Li, X. & Li, Y. Research on reclaimed water from the past to the future: a review. Environ Dev Sustain 24 , 112–137 (2022). https://doi.org/10.1007/s10668-021-01495-w

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167 Water Essay Topics & Research Questions about Water

Looking for a research title about water shortage, conservation, pollution, or treatment? Whatever your area of interest is, you will definitely find a good writing idea in this list of titles for water essays! Topics we’ve collected here are fresh, unique, and current. Go ahead and read them below!

🏆 Best Essay Topics on Water

💡 simple water essay titles, 👍 good water research topics & essay examples, 📌 easy water essay topics, 🎓 most interesting water topics for project, ❓ research questions about water.

• Water Accessibility and Quality
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• How Access to Clean Water Influences the Problem of Poverty
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• Water Pollution Causes, Effects and Solutions
• Don’t Ship Air and Don’t Ship Water Strategies
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• Water and Soil Management Maintaining soil water balance has a long history and is practiced in many countries, arguing that human activities are threatening the quality of water and soil.
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• Fiji Water Quality: Biology Lab Experiment Since Fiji water is among the popular brands in the US, it is essential to evaluate whether it is clean, that is, safe for human consumption.
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• Bottled Water Impacts on Environment As the use of bottled water continue to rise steadily around the world, many critics have focused on its impacts on the environment, economy and other social implications related to the use.
• Water Recycling: Why Is It Important? Different countries face varying challenges in as far as provision of clean water to its population is concerned depending with its economic development level and geographic location.
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• Garbage Pollution’s Impact on Air, Water and Land Garbage pollutes the planet, and to stop this adverse effect, the authorities’ involvement is needed. One solution lies in the plane of economics and politics.
• Benefits of Water Birth Overview Waterbirth remains to be a controversial approach. The studies examined in this paper provide some evidence for the benefits that waterbirth has.
• Analyzing the Use of Water in Danticat, Roumain, and Marshall The use of water in the three novels Roumain’s “Masters of the Dew,” Danticat’s “Krik? Krak!” and Paul’s “Praise Song for the Widow” has a symbolic meaning.
• The Issue of Food and Water Security The global issue for the analysis is food and water security. This is a topical problem nowadays, especially in light of climate change and population growth.
• Solutions for Food and Water Security Issue With many nations encountering food and water security problems, the consequences of such events have become global, giving rise to multiple outcomes this insecurity.
• Water and Its Properties Water is the most abundant liquid on the universe comprising over 70% of earth’s composition. It exists in three forms namely liquid, solid, and gaseous states.
• Water Scarcity as Effect of Climate Change Climate change is the cause of variability in the water cycle, which also reduces the predictability of water availability, demand, and quality, aggravating water scarcity.
• The Problem of Water Scarcity The paper states that although the problem of scarcity of water is severe, it is crucial to take measures to solve it since they can improve the situation.
• Effects of Climate Variability on Water Resources, Food Security, and Human Health Evaluating the effects of climate variability on water, food, and health will help identify the areas for improvement and offer solutions to current environmental challenges.
• Land Usage and Water Quality in Saudi Arabia The effect of land use in Saudi Arabian water quality has intensified the region’s water crisis, causing economic, ecological, and social challenges.
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• Water Quality Improvement for Global Health This proposal determines the necessity of water quality from the perspective of global health. The funding will be provided by the government and non-governmental organizations.
• Bottled Water Impact on Environment This paper seeks to amplify the need for regulation of the used water bottles. It is quite obvious that water bottles are the highest in a number of all bottles thrown away after use.
• All About Water: Problems and Solutions In addition to explaining water benefits, the paper has also shown that many people globally struggle with water shortages or exposure to contaminated water.
• Biogeochemical Cycles: Carbon, Nitrogen, and Water The most common biogeochemical cycles are carbon, nitrogen, and water cycles. The purpose of this paper was to summarize these three cycles.
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• Fiji Water Case Study Analysis Brandon Miller aims to establish a business that is the distribution of Fiji water for Monroe and Wayne market areas.
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• “Bling H2O” Bottled Water in the Australian Market Bling H2O water is the world’s most expensive bottled water. The brand’s creator targeted to sell it to the celebrities who highly esteem their bottled water.
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• Changes in the Global Water Cycle Changes in the climate brought about by global warming have a much bigger likelihood of impacting negatively on the global hydrological cycle.
• Dream Water Company’s Product Marketing The core product is the main benefit that the product brings to the consumer. For Dream Water, the core product is the medication against insomnia.
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• Aspects of Global Pollution of Water Global pollution of water resources has devasting effects on the environment that include the destruction of the ocean ecosystem and biodiversity.
• Water Pollution in the Florida State The researchers claimed that plastic pollution was caused by the tourists and citizens who live along the coastline and dumping from the industries.
• Resolutions to Fight Water Scarcity The World Health Organization outlines water scarcity as a global crisis affecting more than 2.8 billion people.
• The Water Shortage Supply in Las Vegas The water shortage supply in Las Vegas is a major problem due to the city’s reliance on Lake Mead and Colorado Rivers, which are drying up due to droughts.
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• Is Bottled Water Safe for Public Health? Bottled water is just water but is marketed in such a way that makes it appear as healthy because it is positioned as “bottles water is healthy”.
• Water Quality Assessment. Environmental Impact Maintaining good water quality is essential to human health; thus, the recent decades have outstandingly worsened the water across communities worldwide by pollution.
• First Nations Communities Water Resources Drinking water is by no means an infinite resource, but there are places in the world where women and children spend hours each day just to collect it.
• The Global Water Crisis: Issues and Solutions The water crisis has now been associated with the reduction in food quantity besides the scarcity of safe drinking water.
• Water Sector Privatisation in Saudi Arabia The paper explores the decision by the Ministry of Water and Electricity in Saudi Arabia to form the National Water Company to facilitate the privatization process and oversee the regional operations.
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• Green Infrastructure in Water Management This paper evaluates the utility of water management in urban areas from the aspect of perception and interpretation of green infrastructure in water management.
• Water Buffalo Days: Growing Up in Vietnam by Nhuong The book Water Buffalo Days: Growing Up in Vietnam by Nhuong tells the story of a young boy in a central village in Vietnam. The story presents unique characteristics of Vietnam society and culture.
• Agriculture, Water, and Food Security in Tanzania This paper evaluates the strategies applicable to the development and further maintenance of agriculture, water, and food security in Tanzania.
• Relocation of Solar Power System to Easy Life Water Ventures The paper states that having an effective power source will help the organization operate smoothly and sustainably and increase its reputation.
• High-Quality Water Supply in the United States The American community has become more conscious about their health and general physical condition. Consequently, a high-quality water supply stays a priority in many households.
• Assessment: Dubai Electricity and Water Authority As a key component of Dubai’s economy, DEWA is critical in assisting the Emirate’s growth and transition to a zero-economy economy.
• Hyponatremia: How Much Water Do You Actually Need? Some schools, like Mississippi State, do hydration tests before each practice to ensure their players are adequately hydrated.
• Water Pollution and How to Address It A person must protect nature – in particular water resources. After all, the possibilities of water resources are not unlimited and sooner or later, they may end.
• Water Pollution: Effects and Treatment Pollution of water bodies is a serious hazard to humans and the aquatic ecology, and population growth is hastening climate change.
• Examining Solutions for Mitigating the Food and Water Security Issue Hunger, malnutrition, and decreased resource distribution manifest in communities having issues with food and water security, which decreases the well-being of individuals.
• Impact of Water Pollution: Water Challenges of an Urbanizing World Water is a source of life on Earth, and it is one of the very first needs of living beings. It is a vital resource for the development of the economic and social sectors.
• Environment: There’s Something in the Water Environmental racism hurts the natural image of landscapes and negatively affects the atmosphere and reduces the quality and duration of life for minorities.
• Evaluation of Articles on Food and Water Security The two resources chosen for this discussion pertain to food and water security solutions. The scholarly source is visually distinct from the popular source due to its structure.
• The Clean Water Network Support Statement Fresh water has become one of the most valuable resources in the world, around which regional or even global wars may occur in the future.
• Global Societal Issue: Food and Water Security According to research, food and water security is a pertinent global problem in the current decade, with access to food and water becoming scarce in certain world regions.
• Climate Change and Accessibility to Safe Water The paper discusses climate change’s effect on water accessibility, providing graphs on water scarcity and freshwater use and resources.
• The High Heat Capacity of Water The heat capacity of water greatly affects the planet’s climate. At high temperatures, water absorbs heat, and when it gets colder, it gives it away.
• Exploring the Agenda for Fresh Water Supply in Remote Regions The fundamental thesis of this entire paper is that scientific and technological advances catalyze the development of technologies to deliver fresh water to remote areas of Texas.
• What Is Water-Related Terrorism and How to Cope With It? Water-related terrorism includes damaging government facilities, and since water resources are vital for human existence, it is profitable for terrorists to attack them.
• Lake Mattoon: Recreational Site and Water Reservoir Lake Mattoon remains one of Coles county’s best recreation sites and major water reservoirs; it is a big, man-made lake with lush green shores and big fish populations.
• Whirlpool in the Sea off the Coast of Scotland Near Ayrshire Due to Waste Water Stunning drone images near Lendalfoot in South Ayrshire captured a glimpse of a mammoth whirlpool off the Scottish west coast.
• Causes and Risks of Water Pollution The paper describes the effects of water pollution on human health from the perspective of existing findings on this topic and the assessment of information.
• Fresh Water Toxins: Serious Threat to Health This paper discusses fresh water toxins as a serious threat to health, analyzes Los Angeles drinking water, access to clean water and sanitation.
• Safe Drinking Water: Current Status and Recommendations The study proposes the usage of agricultural waste as a sustainable biosorbent for toxic metal ions removal from contaminated water.
• Essentials of Water in Supporting Biological Systems Water is essential in supporting the biological system in various ways; the properties of water help in understanding its importance.
• Underground Water Contamination in St. Louis Mo City In St. Louis Mo City of Missouri State, contamination of underground water is most likely and that is why the water supply is a subject to government policies.
• Twitter Campaign: Impact of Water Runoff Water runoff can cause flooding, which means property damage and mold formation in damp basements and more. This paper is a twitter campaign about the impact of water runoff.
• Water Pollution of New York City Rivers The aim of the analysis was to assess the effects of CSOs on water quality and the environment at different sites along the Harlem River.
• Water Cooling Tower Construction Site’s Problems The paper highlights three major problems at the construction site. They are security, scheduling, and safety problems.
• Recent Water Treatment and Production Developments This study attempts to investigate whether inorganic filters are more suitable for industrial and water treatment processes when compared to organic filters.
• Chemistry: Partitioning Coefficient of the Water The partitioning coefficient of the water solutions with of diuron, decadienal, atrazine, fluoranthene, and desethylatrazine compounds are calculated in accordance with the formula.
• Developing Suspension Carbon Nano-Tubes in Water This paper has discussed nano-tubes and suspension as well as stabilization which make use of Multi-Wall-Carbon-Nanotubes by the function of concentrated SDS.
• Is Bottled Water Dangerous for People and the Environment? The purpose of this paper is to discuss alternative perspectives on bottled water and whether it is dangerous for people and the planet.
• Pressurized Water Reactors: An Analysis The paper describes the operations of a Pressurised Water Reactors (PWR) plant in-depth, discusses the functions of PWR plants, their advantages and disadvantages.
• A Cartographic History of Water Infrastructure and Urbanism in Rome The freshwater available to the city was a huge cultural and economic boon to Roman citizens. Some of this ancient water infrastructure is operational to this day.
• Integrated Water Strategies From Website Water Recycling The website http://waterrecycling.com/ is a front-end of their company showing various services that the company offers in the field of water recycling.
• The Causes of Water Pollution Water pollution is a significant decrease in water resources’ quality due to the ingress of various chemicals and solid waste. The causes of pollution are related to human activities.
• Bottle Water Industry in Current Economic UK Climate The research question is whether bottled water is a necessity or a luxury with regard to the current economic climate in the United Kingdom.
• Political Ecology and Water Wars in Bolivia The given critical assessment will primarily focus on bringing a new perspective to the issue from the standpoint of political ecology.
• The Influence of Water on the Growth of Popcorn Plants The information from the study would aid farmers in identifying appropriate seasons to cultivate popcorn plants based on data of meteorological forecasts.
• Boiling Is a Process That Cools the Water This paper tells that bringing water to a boil while making tea is a progression that cools it since the process lessens the overall temperature.
• Water Conservation Practice in Olympia Olympia city has a comprehensive water conservation program that involves many projects. The city puts much effort into the conservation of water.
• Protecting the Current and Future Water Supply for Rio de Janiero In the current rate of use, as well as the consensus reached by the governing officials in Rio de Janeiro, there will be enough potable water until 2025.
• Water Conservation Practice in Houston From the treatment of wastewater to the reduction of the consumption of the same Houston is an epitome of the increasing need to conserve resources, especially water.
• Burning Issue of Water Pollution in Washington The problem of polluted drinking water in Washington should be solved immediately despite various obstacles, such as pressure for money, etc.
• Drinking-Water in Third World Countries The shortage of drinking water in countries of Third World and the public controversy, surrounding the issue, illustrates the validity of this thesis better then anything else.
• Bottled Water: Environmental and Cultural Impact The consumption of bottled water has an impact on society. Appropriate strategies must be implemented to ensure that the hazards associated with bottled water are reduced.
• Bottled Water Status in the UK With the current economic climate in the UK, the issue of whether bottled water has become a luxury or a necessity.
• Underground Water Overdraft in Southern California In California, the overuse of underground water reserves and the resultant overexploitation (overdraft) led to a serious water resources deficit.
• Water and Soil Pollution: Effects on the Environment Water and soil pollution is the process of contaminating water and soil. In this project, we will investigate the apparent main pollutants of the Spring Mill Lake.
• Bottled Water: Culture and Environmental Impact Bottled water as a particular branch of industrial growth in countries throughout the world represents the source of environmental pollution.
• Alternative Energy Sources: A Collaborative Approach in Water Management With the increasingly high prices of gasoline in particular and fossil fuels in general there is a need to find an alternative source of energy.
• Polycyclic Aromatic Hydrocarbons Effect on Water Polycyclic aromatic hydrocarbons (PAHs) constitute one of the largest groups of compounds that produce widespread organic environmental pollution posing a risk to marine biota
• Lack of Water in California as an Environmental Issue California can run out of water because of technological and social problems that affected the region. Defining water resources’ “development” is critically important.
• Potential Threats to Water Supplies in Ottawa The purpose of the research is to identify the distribution of threats to drinking water in the city and determine who might benefit and who might be harmed in the process.
• Water Quality in Savannah, Georgia The City of Savannah Water Supply and Treatment Department conducts numerous annual tests to ensure that drinking water in the region is safe for human consumption.
• Water Treatments and Maximum Plant Height The first research question was how different water treatments affect maximum plant height. The experiment involved 12 plants – 6 plants for each type of water.
• Water Pollution Index of Batujai Reservoir, Central Lombok Regency-Indonesia Despite having 6% of the world’s water resources, Indonesia’s environmental policies have not only been raising concerns but also pushed the country to the brink of water crisis.
• Water Resources in Australia: Usage and Management Australia is one of the driest continents in the world. Various governmental and non-governmental institutions have teamed up to face the challenges facing people as far as water is concerned.
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• Active Remediation Algorithm for Water Service in Flint The Active Remediation algorithm aims to inspect the water service in Flint, Michigan, and identify those lead pipes that need to be replaced by copper pipes.
• Water Savings and Virtual Trade in Agriculture Water trade in agriculture is not a practice that is unique to the modern generation. The practice was common long before the emergence of the Egyptian Empire.
• Virtual Water Trade of Agricultural Products Virtual water trade is a concept associated with globalization and the global economy. Its rise was motivated by growing water scarcity in arid areas around the world.
• Virtual Water Savings and Trade in Agriculture The idea of virtual water was initially created as a method for assessing how water-rare nations could offer food, clothing, and other water-intensive products to their residents.
• Environmental Legislation: Clean Water Act Clean Water Act determines water quality standards, serves as a basis for the enactment of pollution control programs, and regulates the presence of contaminants in surface water.
• Third-Party Logistics, Water Transportation, Pipelines Transportation plays a crucial role in today’s business world. This work shows the benefits and limitations of third-party logistics providers, water transportation, and pipelines.
• Water Quality and Contamination In this paper, carries out detailed experiments on the bottled and tap water available to consumers to establish whether it is worthwhile to purchase bottled water.
• Oil, Water and Corruption in Central Asian States The region of Central Asia has been a focus of the world’s political and economic attention due to its rich oil and gas resources. Corruption is the main curse of Central Asian states.
• Water Scarcity Issue and Environment The paper answers the question why to be worried about running out of drinking water even though the earth’s surface is mostly made of water.
• Environmental Studies: Water Recycling Different countries face varying challenges in as far as the provision of clean water to its population is concerned depending on its economic development level and geographic location.
• Water Pollution This essay seeks to examine the concept of water pollution, its causes, effects and solutions to water pollution.
• How Does Water Pollution Affect Human Health?
• Are Sports Drinks Better for Athletes Than Water?
• What Happens if You Don’t Filter Your Water?
• Can Game Theory Help to Mitigate Water Conflicts in the Syrdarya Basin?
• How Can We Reduce Water Scarcity?
• Are Water Filters Really That Important?
• How Much Water Do We Need to Feed the World?
• Why Is Water Important for Food Production?
• Can Markets Improve Water Allocation in Rural America?
• How Can We Reduce Water Consumption in Food Industry?
• Can Public Sector Reforms Improve the Efficiency of Public Water Utilities?
• What Are the Modern Technologies Used to Treat Water?
• How Does Water Pollution Affect Global Warming?
• Can Sea Water Generate Usable Energy?
• What Are the Steps Taken by the Government to Reduce Water Pollution?
• Can Sugar Help Lower the Freezing Point of Water?
• Do We Need More Laws to Control Water Pollution?
• Can the Global Community Successfully Confront the Global Water Shortage?
• What Is the Government Doing to Save Water?
• Can Virtual Water ‘Trade’ Reduce Water Scarcity in Semi-arid Countries?
• Does Urbanization Improve Industrial Water Consumption Efficiency?
• How Has Technology Helped Us Save Water?
• Does Piped Water Improve Household Welfare?
• Can Water Pollution Policy Be Efficient?
• How Does Green Infrastructure Improve Water Quality?

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StudyCorgi. (2021, September 9). 167 Water Essay Topics & Research Questions about Water. https://studycorgi.com/ideas/water-essay-topics/

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StudyCorgi . "167 Water Essay Topics & Research Questions about Water." September 9, 2021. https://studycorgi.com/ideas/water-essay-topics/.

StudyCorgi . 2021. "167 Water Essay Topics & Research Questions about Water." September 9, 2021. https://studycorgi.com/ideas/water-essay-topics/.

These essay examples and topics on Water were carefully selected by the StudyCorgi editorial team. They meet our highest standards in terms of grammar, punctuation, style, and fact accuracy. Please ensure you properly reference the materials if you’re using them to write your assignment.

This essay topic collection was updated on January 9, 2024 .

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Water Supply and Sanitation in Rural Communities

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Access to water and sanitation is still a problem especially in middle-income and developing countries. According to the Joint Monitoring Program report there are 2 billion people that still lack access to safely managed water services and 3.6 billion people lack safely managed sanitation services. In ...

Keywords : Water, Sanitation, Rural population, Human rights, Gender, Climate Change

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