Public responses to water reuse - Understanding the evidence

Comparative life cycle assessment of remote potable water supply for the Department of Defense

The Department of Defense (DOD) and other agencies, including relief organizations, require potable water for remote missions around the globe. As part of recent initiative by the U.S. Federal government through Executive Order 14057, the DOD has been instructed to investigate the sustainability of operations and practices within the context of climate change. One such practice that needs to be addressed is the procurement of potable water, an essential requirement of any remote mission or location. Currently, there are three primary means of procuring potable water at remote locations: bottled water, on-site purification, or tie-in to existing, local infrastructure. The first two operations are often considered the most secure options, but have sustainability concerns. The purpose of this study is to compare the environmental impacts of bottled water procurement versus on-site treatment via a mobile Reverse Osmosis Water Purification Unit (ROWPU), which uses multiple levels of filtration to make potable water from a local source. A cradle-to-gate assessment was developed for both systems to compare different options for potable water supply. An in person inventory was paired with data taken from the Ecoinvent 3.8 database to directly compare the two systems. The two systems are compared on a 5-year timeline to analyze the environmental impact of repeated bottled water transport versus diesel generator-fueled on-site treatment. Across all impact categories, the results indicate that high energy costs of the reverse osmosis process have significantly less impact on the environment than the repetitive transport and procurement of bottled water. The results of the study have important implications for advancing sustainable operations for remote communities or temporary settlements.

Behaviour of dissolved inorganic salts in the cooling water of a nuclear power plant open recirculation system and formation of water discharge

The main problem in the operation of nuclear power plants (NPPs) is the scale formation of mineral impurities in an open recirculating system (ORS). The discharge of water from an ORS into natural water bodies can alter the chemical equilibrium of wastewater components, necessitating continuous monitoring. The purpose of this study was to analyse the behaviour of dissolved inorganic salts (DIS) in water within an ORS during water treatment, using the Rivne Nuclear Power Plant (RNPP) as a case study. Moreover, the analysis impact of their discharge with return water in the Styr River. The DIS concentration has a significant impact on the efficiency of the system and the environmental of an ORS power plant. Altogether, each of the DIS components was analysed separately using the standard measurement methods, statistical methods of data processing and correlation analysis. In addition, the annual discharge of the DIS components was calculated, and the amount of discharge was assessed for compliance with the maximum discharge limit. Thus, the impact of the formation of DIS and the variations in their concentration levels upon the discharge of wastewater into a natural water body were examined.

Understanding global perspectives for the acceptance of community sanitation welfare schemes through a localised qualitative survey in Kho Nagorian, Jaipur, India

Community sanitation is a fundamental human right and need. Every year, as per the World Bank, total cost of providing sanitation services is estimated at around 114 billion USD per year. In India, Swachh Bharat Abhiyan (SBA), a public welfare scheme (PWS), is aimed at addressing community sanitation problems. Despite the successful implementation of SBA, local communities still practise open defaecation. To deduce the behavioural patterns governing communal toilet use, interviews were conducted with the local communities in the Kho Nagorian area of Jaipur, Rajasthan, India. This qualitative survey examined attitudes towards the construction of a toilet, awareness towards the SBA scheme, and the willingness to use excreta-based pit humus. The study then discusses the factors that increase the local community's willingness to use these toilets. Results show that open defaecation is still prevalent in society. One way to foster the adoption of toilets is that the construction materials should mainly consist of local materials. As a recourse, places of worship could be used to influence people's perception of hygiene. In addition, community toilets should be cleaned often as well. PWS should not be made accessible at no cost to prevent a sense of entitlement among the people. A small sum should be charged to increase social responsibility towards the PWS. Another way to curb open defaecation is to tap into the sense of entitlement by making effective use of social campaign programs. Further, cross-table analysis revealed that the locals were inclined to use a toilet if they have invested in it. Advertisements were found to be ineffective, and proposals were made to make them effective. These findings aid in understanding public perceptions and can guide the development of public policies. The findings also assist in making tax distribution decisions that reflect public concerns, attitudes, and values.

Exploring the recycled water acceptance based on the technological perspective of UTAUT2: a hybrid analytical approach

Introduction

The development of advanced sewage technologies empowers the industry to produce high-quality recycled water, which greatly influences human's life and health. Thus, this study investigates the mechanism of individuals' adoption of recycled water from the technology adoption perspective.

Methods

Employing the mixed method of structural equation modeling and artificial neural network analysis, we examined a research model developed from the extended Unified Theory of Acceptance and Use of Technology (UTAUT2) framework. To examine the research model, this study employs a leading web-survey company (Sojump) to collect 308 valid samples from the residents in mainland China.

Results

The structural equation modeling results verified the associations between the six predictors (performance expectancy, effort expectancy, social influence, facilitating conditions, environmental motivation, and price value), individuals' cognitive and emotional attitudes, and acceptance intention. The artificial neural network analysis validates and complements the structural equation modeling results by unveiling the importance rank of the significant determinants of the acceptance decisions.

Discussion

The study provides theoretical implications for recycled water research and useful insights for practitioners and policymakers to reduce the environmental hazards of water scarcity.

The potential for water recovery from urban waste water - The perspective of urban waste water treatment plant operators in Poland

Water recovery from waste water has become an essential element of the circular economy in the Baltic Sea region. However, there is little data on the possibility of using water recovered from urban waste water. A survey was conducted to learn the opinions of Poland waste water treatment plant operators. They were asked whether they recovered water for internal or external needs. Respondents indicated opportunities and barriers in this activity. The opinions of 107 operators show that work is underway on closing internal circuits in urban WWTPs. These solutions are technically relatively easy to implement and show measurable benefits (i.e., saving drinking water). However, water recovery for external purposes is rare and is at a very early stage. Despite this, the potential is significant, although many financial, organizational, technical, and mental barriers exist. The most critical challenge is the safe use of reclaimed water and the cost-effectiveness of the solutions. The survey also shows a need for education and involvement of the public.

Not all information is informative: An exploration of educational content on recycled potable water knowledge and acceptance

As drought and water shortages threaten access to safe water supplies globally, finding ways to increase public acceptance of recycled water has become increasingly important. Educational interventions have often been explored as a potential method to help overcome public distaste for recycled water. However, in past research, the effects of educational interventions have tended to be modest, leading to some skepticism over the ability of public information campaigns to truly increase acceptance. We propose that, at least in part, these modest effects of education may be driven by differences in the ability of some types of educational content to increase recycled water knowledge and subsequent acceptance (e.g., some content may be too complex for a lay audience or may be insufficient to adequately address the concerns that drive one's apprehension towards recycled water). Thus, we developed and tested an educational video split into four distinct areas of educational content related to potable water reuse: (1) need for recycled water, (2) approaches to implementing recycled water (e.g., through direct, indirect, or de-facto reuse), (3) purification technology, and (4) locations and testimonials of actual implementation. In two experiments (Ns = 711, 385), we found that content illustrating approaches to implementing recycled water and locations using it led to medium to large increases in knowledge and acceptance. These results imply that given limited time and resources, brief information about these topics may increase acceptance better than alternative information. Moreover, these results underscore a need to more carefully consider the content used in educational campaigns, as not all information is equally likely to produce desired effects.

Making waves: Promoting municipal water reuse without a prevailing scarcity driver

The wealth of water reuse research in scarcity and/or rapid urbanisation contexts has underpinned significant change in many relatively water scarce contexts. Less progress has been achieved in water rich contexts; a fact illustrated by the lack of change on the ground. The Climate Emergency demands that all municipalities urgently contribute to more efficient resource management of water. Consequently, to advance municipal scale reuse projects in locations where scarcity is not forcing the issue, for example Scotland, there is a need to predicate water reuse on different drivers, specifically climate change and the circular economy. Moreover, greater contextual sensitivity needs to be applied when exploring barriers to reuse to more critically exploit opportunities, for example avenues to reform complex regulatory frameworks, different contingencies around trust, and different potential degrees of the yuck factor. To achieve this, new initiatives need to be urgently undertaken to consider the barriers to reuse that will not be swept aside by the imperative of  scarcity. The notion of a yum factor, whereby positive sentiments are nurtured to combat instinctive repugnance, coined as yuck by the bioethicist Arthur Caplan, is advanced as a strategic objective to promote more rapid expansion of municipal scale reuse.

Envisioning the innovative approaches to achieve circular economy in the water and wastewater sector

Given the challenges of urbanization and rapid resource depletion, policymakers have been compelled to abandon the old sequential paradigm of "take-make-use-dispose" to a circular approach that prioritizes preservation of natural resources. The circular economy represents a sustainable management concept that focuses on reducing, recovering, reusing, and recycling waste. While significant strides have been made in implementing circular economy principles in various industries such as automotive, electronics, and construction, particular attention has been given to the water and wastewater domains due to imbalances in water resources. Here we review the global progress of circular economy adoptability in the water and wastewater domains, considering technical, environmental, economic, and social perspectives. It assesses the current state of circular economy integration in the wastewater domain worldwide and presents approaches to promote and accelerate its adoption. The study critically examines the principles of waste management, known as the 6Rs (reclaim, restore, recycle, reduce, recover, reuse), in order to formulate effective strategies for integrating circular economy practices in the water and wastewater domains. Additionally, the study provides an overview of existing research conducted on different aspects of circular economy. Finally, the study analyzes the challenges and opportunities associated with implementing circular economy principles in the water sector.

Evaluating the impact of water reuse educational videos on water reuse perceptions using EEG/event related potential

As climate change and population growth increasingly stress freshwater resources, government agencies and scientists have recognized the importance of water reuse (the beneficial use of reclaimed or recycled water). While end users (municipalities and farmers) are largely open to exploring water reuse, a barrier to using this water source is the public's negative perception, or the 'yuck factor'. Recognizing that water reuse is becoming a necessity, there is an urgent need to determine how to improve public acceptance of this water source. Increasing knowledge has been identified as a critical method for improving the adoption of sustainable practices, but to date, there has been a lack of outcome studies on the ability of water reuse education materials to change perceptions. Previous studies have relied heavily on self-reported concerns and perceptions which are limited by bias and social expectations, and their results have failed to substantially change water reuse education efforts, and by extension failed to substantially improve water reuse perceptions. We propose the integration of psychology for evaluating the effectiveness of water reuse education and outreach efforts. The purpose of this study was to determine if water reuse educational videos modulate perceptions of water reuse terms. Participants were recruited from a university campus and completed pre-intervention surveys on water reuse knowledge, willingness to use recycled water, and preferred water reuse information sources. We then measured changes in neural activity in response to multiple categories of water reuse terms pre- and post-exposure to water reuse education videos using electroencephalogram (EEG). Through EEG we measured event related potential (ERP), which assesses sustained engagement with the cues (late positive potential (LPP) amplitude), and alpha power. Participants also completed a pre/post exposure battery involving five tasks, in randomized order, presented before and after viewing videos. Sixty-eight percent of survey participants had previously heard of water reuse and 91% reported willingness to use recycled water for at least one activity. Participants reported obtaining water reuse information mostly from the internet (77%) and preferred to receive additional information mainly by watching online videos (73%). We observed significant increases in alpha power, corresponding to feelings of relaxation, in response to seven of eight water reuse term categories post-video exposure. These findings show that water reuse educational videos can change perceptions of water reuse. Our results point to the possibility of validating and increasing the effectiveness of water reuse education materials using sophisticated neurocognitive measures.

Life cycle sustainability assessment of advanced treatment techniques for urban wastewater reuse and sewage sludge resource recovery

Wastewater treatment plants can become a source of valuable resources, such as clean water, energy, fuels and nutrients and thus contribute to the sustainable development goals and a transition to a circular economy. This can be achieved by adopting advanced wastewater and sludge treatment techniques. However, these have to be evaluated on their sustainability to avoid any unintentional consequences. Therefore, this paper presents a life cycle sustainability assessment of advanced wastewater and sludge treatment techniques by integrating the environmental, economic and social aspects. The options considered for advanced wastewater treatment are: i) granular activated carbon; ii) nanofiltration; iii) solar photo-Fenton; and iv) ozonation. The technologies for advanced sludge treatment are: i) agricultural application of anaerobically digested sludge; ii) agricultural application of composted sludge; iii) incineration; iv) pyrolysis; and v) wet air oxidation. The results for the advanced wastewater treatment techniques demonstrate that nanofiltration is the most sustainable option if all the sustainability aspects are considered equally important. If, however, a higher preference is given to the economic aspect, ozonation and granular activated carbon would both be comparable to nanofiltration; if the social aspect is considered more important, only activated carbon would be comparable to nanofiltration. Among the sludge treatment methods, agricultural application of sludge is the most sustainable technique for mean-to-high resource recovery. If the recovery rate is lower, this option is comparable with incineration and pyrolysis with high recovery of their respective products. This work helps to identify the most sustainable techniques that could be combined with conventional wastewater treatments for promoting wastewater reuse and resource recovery across a wide range of operating parameters and products outputs. The findings also support the notion that more sustainable wastewater treatment could be achieved by a circular use of water, energy and nutrients contained in urban wastewaters.

Adoption of water reuse technologies: An assessment under different regulatory and operational scenarios

Water reuse technologies may alleviate the water scarcity problems that affect many world regions, but their adoption is still limited. In particular, key actors in the adoption of water reuse technologies are water utilities, that provide both urban water and wastewater treatment services. Water utilities are embedded in the urban water system, which includes several stakeholders (urban water users, citizens at large, the environment) that may drive or pose barriers to water reuse adoption. Therefore, to ensure a smooth introduction of water reuse technologies, it is fundamental to understand how water reuse interacts with the existing urban water system and impacts its stakeholders. This paper contributes to the ongoing debate on water reuse by conceptualizing the interaction between water reuse technologies and the urban water system and its stakeholders, and addressing the adoption decision of water utilities by assessing its economic and environmental consequences. Based on a review of literature, policy and other secondary documents, and on primary data coming from interviews with experts from a water utility operating in Southern Italy, the study models the utility's response to a shift from urban to reuse water. It then simulates how reuse water introduction impacts on the utility and other stakeholders of the water system, under various regulatory and operational scenarios defined through a thorough analysis of policy documents and literature. Results show that the adoption of water reuse reduces the utility's margin by cannibalizing urban water demand, but appropriate policy measures may enhance the economic sustainability of reuse. System-level performances, such as impact on freshwater savings, costs for users, effects on the public budget, are also assessed, showing how different regulatory options moderate the intensity of impacts for the different stakeholders of the water system. Furthermore, the adoption of reuse water by the most distant users is found to enhance the economic sustainability of reuse and positively impact the utility's margin.

Urban water as an alternative freshwater resource for matching irrigation demand in the Bengal delta

Rapid changes in climate patterns, population growth, urbanization, and rising economic activities have increased the pressure on the delta's freshwater availability. Bangladesh's coastal planes suffer from a shortage of good quality irrigation water, which is crucial for peri-urban agriculture and at the same time, a high volume of untreated wastewater is discharged into the surface water. This calls for a transition towards efficiently managing and (re)using available urban water resources for irrigation, which is addressed in this paper. A quantitative match between the irrigation demand and potential freshwater supply has been assessed considering different urban water generation scenarios. The FAO AquaCrop model has been used to calculate the irrigation water demand for Boro rice during the dry period. Results indicate that 7.4 million m³ of irrigation water is needed, whereas over 8.2 million m³ of urban water is being generated during the dry season. Simultaneously, mismatches between irrigation demand and alternative water supply mainly occurred in February and March, which could be resolved with water storage capacities. However, to make urban water reuse a reality, the water management policy needs to change to facilitate the construction of required infrastructures for collection, treatment, and storage. The proposed method helps realize the urban water's hidden potential to sustain agricultural activities in the delta areas.

Socio-psychological determinants of Iranian rural households' adoption of water consumption curtailment behaviors

Dealing with a growing population and a shortage of drinking water is a major challenge for politicians and planners. A key factor in ensuring a sustainable water supply is water conservation at the household level, which can increase productivity and save water resources. Therefore, promoting water consumption curtailment behavior will contribute significantly to reducing the global water crisis, especially in arid and semi-arid regions. Water consumption curtailment behaviors depend on individuals’ encouragement to choose and adopt voluntary behaviors and cannot be enforced by any political or planning power. In order to encourage water conservation those social and psychological factors should be considered that influence individuals to participate or adopt water consumption curtailment behaviors. Therefore, the study of factors influencing rural households' water consumption curtailment behaviors is of great importance. This study aimed to describe the socio-psychological factors influencing water consumption curtailment behaviors among rural households in southwestern Iran. The extended theory of planned behavior (ETPB) was used as a theoretical framework in this study along with descriptive norms (DN), moral norms (MN), habits, and justification. Data were collected using a questionnaire and analyzed using structural equation modeling (SEM). The results showed that ETPB can explain 35% and 54% of intention and water consumption curtailment behaviors among rural households in Iran. Our findings may assist policymakers in reducing domestic water consumption.

Analysis on the Knowledge Evolution Path of Public Acceptance of Reclaimed Water Research

Reclaimed water is an important component of available water resources, and public acceptance of reclaimed water is a key factor influencing the implementation of reclaimed water reuse projects. For this reason, it has received attention from different scholars in the international community. Based on the literature data on public acceptance of reclaimed water, this study analyzes the development status of research results and explores the knowledge evolution path with the help of bibliometric methods. Our results show that the field of research on public acceptance of reclaimed water began to grow rapidly after 1990, and identify influential countries, institutions, authors, and journals in the field. In addition, “water quality”, “public health”, and “irrigation” are themes that run throughout the research, and “sustainable development” and “potable reuse” are the emerging research hotspots. As research progresses, the scope of research on reclaimed water reuse and its influencing factors continues to expand, and reclaimed water management policies and standards continue to improve. In the future, in order to improve public acceptance, finding how to improve the public’s risk perception and trust in reclaimed water will become a central research focus.

Interplay of Message Frame and Reference Point on Recycled Water Acceptance in Green Community: Evidence from an Eye-Tracking Experiment

Public rejection of recycled water hinders the application of recycled water use projects in green communities. An effective information outreach strategy could help to overcome this obstacle. This study used message frames and reference points as control variables to design experimental materials and conduct eye-movement experiments to determine the effect of different information promotion strategies. The results of the study show that: (1) compared with the loss frame, the gain-framed messages are more effective; (2) self-referencing messages are more suitable for recycled water use promotion than other-referencing messages; (3) message frame (gain vs. loss) and reference point (self vs. others) have an interactive effect on the public’s information cognitive behavior; (4) the average duration of fixations for advertising message plays an intermediary role in the path of message frame and reference point jointly influencing the public acceptance. This study provides managerial implications for determining information dissemination strategies for applying recycled water-use projects in green communities.

Urban Residents' Acceptance Intention to Use Recycled Stormwater-An Examination of Values, Altruism, Social and Cultural Norms, and Perceived Health Risks

Public acceptance is the basic premise for the implementation of stormwater reuse projects anywhere in the world. Based on the theory of planned behaviour, this study constructed a hypothesized model of urban residents’ intention to use recycled stormwater for non-potable residential purposes. Having received 669 valid questionnaires from urban residents in Taiyuan City, a Structural Equation Model was used to analyze their acceptance intention to use recycled stormwater. Results of the study showed that the degree of human contact with recycled stormwater influenced respondents’ acceptance intention to use it for that purpose, which is consistent with previous studies. The impact of factors, including valuation of stormwater, emotions, perceived health risks, or trust in government, on respondents’ acceptance intention to use recycled stormwater was found to be not significant, which adds to the inconsistent literature. The unique contributions of the study to literature include that altruism and social and cultural norms were found to have significantly positive impacts on residents’ acceptance intention to use the water, while social and cultural norms demonstrated a more significant impact. This finding is perceived to relate to the collectivism of Chinese culture; however, to what extent the relation could be requires further research to verify. The study also makes contributions to methodology by using social networking (WeChat Moments) to collect data in social science studies.

RECLAMO: Unlocking the potential of wastewater reuse for agricultural irrigation in Spain

Increasing water scarcity is encouraging the use of unconventional water resources. In recent years, the European Union has launched numerous initiatives to promote and facilitate water reuse for agricultural irrigation. Today, the use of reclaimed water for agriculture has become an alternative, reliable and safe source of water supply and an indispensable water planning tool, especially in the area of southern Europe. However, water reuse for irrigation is currently far below its potential. Numerous barriers prevent its development and call for a detailed analysis of the different aspects affecting reclaimed water reuse, through an integrated and multidisciplinary approach.

A multidisciplinary research team from Universidad Politécnica de Madrid, consisting of agronomists, hydrologists, chemists and agricultural economists, will work on the RECLAMO Project (https://blogs.upm.es/reclamo/), with the aim of providing solutions and recommendations aimed at promoting the full development and use of reclaimed water for irrigation in areas of Spain with marked water stress.

For this purpose, project activities will be developed in two selected case studies (the Segura Basin, leader in water reuse in Spain and the Guadiana Basin, with success stories, but low levels of water reuse) and organised according to five axes: 1) development of a comprehensive knowledge-base covering the regulatory, technical, socio-economic and environmental aspects of reclaimed water reuse in agriculture; 2) participatory development of future scenarios exploring possible strategies, barriers and opportunities, in relation to the expansion of the use of reclaimed water for irrigation; 3) impact analysis of the strategies identified at different scales (crop, farm, (sub-)basin), through the development of an integrated modelling platform (hydrologic-agronomic-economic models); 4) Development of a roadmap and policy recommendations to achieve the full development and use of reclaimed water reuse for irrigation; 5) Dissemination of knowledge and promotion of science-policy-society dialogue.

To this end, RECLAMO will collaborate closely with experts and stakeholder groups that will play a key role in the project in co-creating the scenarios and modelling tools and validating the results. The project will also seek for synergies and complementarities with other similar projects and explore new ways of collaborating with companies and research groups that allow research to continue and expand beyond the spatial and temporal limits of the project.

RECLAMO’s results will promote an integrated approach to the sustainable management of water resources in water-stressed areas, including reclaimed water management. The integrated modelling platform developed in the project will allow policy-makers and water users to benefit from an improved understanding of the interactions between the social, economic and environmental aspects of water systems, in the context of climate and socio-economic change that will lead to better informed decision-making to address future water challenges. In addition, RECLAMO is expected to contribute to raising awareness about the use of reclaimed water reuse in agriculture as a safe and sustainable practice and to improve its social acceptance by producing science-based knowledge that provide evidence on the benefits derived from its use.

Institutional challenges and stakeholder perception towards planned water reuse in peri-urban agriculture of the Bengal delta

The indirect, unplanned use of urban wastewater by peri-urban farmers in developing countries poses a severe risk to the environment and the farmers. Planned water reuse could contribute substantially to the irrigation water demand in peri-urban agriculture and minimize the risk. However, implementing such practice requires a thorough evaluation of stakeholder's perception and the scope within the existing organizational structures. This paper aims to assess the level of awareness, perception, and willingness of different stakeholders toward current practices and the prospect of urban water reuse in Khulna City - one of the most vulnerable cities located in the southwest of Bangladesh due to the consequences of rapid climate changes in the Bengal delta. Also, institutional arrangements and their functioning were analyzed to understand the current sectoral performance. One questionnaire with 385 respondents from the urban area, 32 in-depth interviews and one focus group discussion with farmers in the peri-urban area, and ten interviews with key informants from the government and non-government organization was conducted. Results indicate an overall positive attitude among major stakeholder groups toward planned water reuse for peri-urban agriculture. More than half of the citizens (53%) are willing to pay for the treatment of wastewater and majority of the farmers (66%) are willing to pay for the supply of better-quality irrigation water. However, the public sector responsible for wastewater collection and treatment requires adjustment in rules and regulations to implement planned water reuse. Interrelated factors such as lack of transparency and coordination, shifting responsibilities to other organizations, lack of required resources need to be addressed in the updated rules and regulations. Strategies to enforce current regulations and align all stakeholders are also crucial for collection and treatment of wastewater and its subsequent use for crop production.

A Systemic View on Circular Economy in the Water Industry: Learnings from a Belgian and Dutch Case

Water is fundamental to our existence and has increasingly been put under pressure by soaring population growth, urbanization, agricultural farming and climate change; all, of which impact the quantity and quality of our water resources. Water utilities (WUs) are challenged to provide clean, safe drinking water when faced with aging, costly infrastructure, a price of water that is not reflective of its true value and the need for infrastructure to remain resilient in a time when threats of floods and droughts are pervasive. In the linear take-use-discharge approach, wastewater is treated only to be returned to waterways and extracted again for treatment before drinking. This can no longer sustain our water resources as it is costly, energy-intensive and environmentally unsound. Circular economy (CE) has been gaining attention in the water industry to tackle this. It follows the 6Rs strategy of reduce, reuse, recycle, reclaim, recover and restore to keep water in circulation for longer and reduce the burden on natural systems. The aim of this study is to determine what the economic and operational system effects of CE are on WUs, informing them of CE’s potential to change their business operations and business model while highlighting its associated challenges. Based on a review of literature, input from expert interviews (Q4 2019) and case studies, an economic view of the urban water system is qualitatively modeled, on top, of which a circular water economy system is designed using a causal loop-diagramming system mapping tool. Digitalization, water reuse and resource recovery were determined to underpin circularity in water, providing operational benefits through efficiencies and diversification of revenue streams. However, issues of investment and a missing enabling legal framework are slowing the rate of uptake. On this basis, CE represents both a challenge and an opportunity for the water industry.

Virus removal by membrane bioreactors: A review of mechanism investigation and modeling efforts

The increasing pressure on the global water supply calls for more advanced solutions with higher efficiency and better sustainability, leading to the promptly developing water reclamation and reuse schemes including treatment technologies and risk management strategies where microbial safety is becoming a crucial aspect in the interest of public health. Backed up by the development of membrane technology, membrane bioreactors (MBR) have received substantial attention for their superiority over conventional treatment methods in many ways and are considered promising in the water reclamation realm. This review paper provides an overview of the efforts made to manage and control the potential waterborne viral disease risks raised by the use of effluent from MBR treatment processes, including the mechanisms involved in the virus removal process and the attempts to model the dynamics of the removal process. In principle, generalized and integrated virus removal models that provide insight into real-time monitoring are urgently needed for advanced real-time control purpose. Future studies of approaches that can well handle the inherent uncertainty and nonlinearity of the complex removal process are crucial to the development and promotion of related technologies.

Assessing the public perceptions of treated wastewater reuse: opportunities and implications for urban communities in developing countries

Wastewater reuse has become an integral part of Integrated Water Resources Management and thus plays a role in securing the water needs for future generations. This study aimed at determining the perceptions of Canaanland, an emerging urban community in Ogun State, Nigeria, on treated wastewater reuse for several purposes. Data were collected through questionnaires administered to the city residents (n = 244). Findings revealed that the city was aware of the economic and environmental benefits of wastewater reuse but would prefer reuse schemes that involved less human contact such as flushing toilets, electricity generation, building construction, and car wash. The least preferred option was for potable purposes. The community also revealed that they would be willing to accept wastewater reuse as long as it is endorsed by medical doctors, university professors, and experts. However, 45.5% of the respondents were from the Covenant University academic environment. Also, an assessment was carried out to ascertain the implications and opportunities for wastewater reuse in the city. Findings indicated that wastewater reuse involves several complexities and interlinkages, which revolve around political and decisional factors, economic and social factors, environmental factors, and technological factors. From the study, policy and decisional suggestions and a wastewater process flow were developed for more efficient wastewater management within developing cities. A study was carried out on eight cities from developing nations that have created a framework for wastewater management using several approaches. Also, a summary of findings reveals that if adequately researched, cheap and alternative means of wastewater treatment and reuse could be developed for electricity generation, carwash, and firefighting for developing nations. The result of this research can be used to address public anxieties regarding wastewater-reuse practices. Additionally, this study hopes to aid successful wastewater management schemes in the foreseeable future.

Why (Not) Desalination? Exploring Driving Factors from Irrigation Communities’ Perception in South-East Spain

Desalination for sustaining agricultural production is conceived as an alternative water source in some Mediterranean countries faced with climatological and hydrological constraints. Although high costs are often cited as limiting factors, how farmers discern desalinated water has not been discussed in-depth in the literature. This paper aims to deepen how desalination is perceived by irrigators, what driving factors are affecting irrigation communities’ decision-making processes, and what learnings can be drawn from their experiences regarding desalination acceptance or rejection. Eleven irrigation communities have been selected from Alicante and Murcia regions (South-East Spain), which account for more than 60,000 irrigators and 120,000 ha. Questionnaires were conducted between March and December 2019. Results highlighted the main advantages (water availability and supply security) and disadvantages (high price affecting profitable crop options, high-energy consumption, water quality standards, the production capacity of desalination plants, no seasonal variation in water production, and shortages due to technical problems) of using desalinated water. Additionally, through the analysis of regional and national press news, it can be concluded that socio-political aspects, such as corruption, cost overruns, and political disputes are also considered.

Analysis of Barriers and Opportunities for Reclaimed Wastewater Use for Agriculture in Europe

This paper presents an analysis of the perception regarding reclaimed wastewater reuse in agriculture conducted in the European Union regions. The analysis is based upon a SWOT framework and applies a cluster analysis to reduce the dimension of the responses enabling an assessment of the different perceptions of water reuse. More than one hundred key actors identified among the regions participated in the evaluation of the relevance of aspects identified. The results indicate some groups of countries according to natural conditions (water scarcity) and the strategic role of agriculture as a key factor to determine agent’s perceptions and attitudes. The results indicate that the forthcoming EU regulation of water reuse should focus in the problems of the perceived high cost of reclaimed water for farmers and the sanitary risk perception for irrigated crops by consumers as the critical points for fostering the use of reclaimed water in agriculture and the need for regional implementation of the global regulatory framework.

Water quality perceptions and private well management: The role of perceived risks, worry and control

Mismanagement of drinking water supplies can pose serious public health risks. There are many concerns about water source management among private well owners, as they are often solely responsible for maintaining their wells, and monitoring and testing of their own water quality. Lack of worry about contamination and a strong sense of control over risks in relation to drinking water quality have been identified as important factors that influence peoples' perceptions and behaviour. In this paper, we investigated how worry and perceived control moderate the influence of risk perceptions on water quality perceptions and well owners' maintenance behaviours. We compare a sample of private well owners (N = 167) with a sample of members of Group Water Schemes (GWS) (N = 160) and people who are supplied via the public mains (N = 195), to validate our results. We found that, in comparison to the other groups, well owners believe that water from private wells is superior and they express a higher level of control over contamination risks of their drinking water. Moreover, strong feelings of control suppress their perceptions of risk in relation to water quality. However, well owners who feel largely in control also maintain their well more frequently. We discuss the implications of these results for communication strategies with well owners.

Measuring objective knowledge of potable recycled water

Reliable clean drinking water is becoming increasingly scarce. One potential additional source of drinking water is recycled water. However, public acceptance of potable recycled drinking water is low. One likely factor involved in the acceptance of recycled drinking water is objective knowledge about recycled water. In three studies (N = 229,  590, and 200), we developed a 34-item measure of objective knowledge of recycled drinking water. The objective knowledge measure was often a strong and unique predictor of intentions to accept and use recycled drinking water compared to other prominent factors including disgust and subjective knowledge of recycled water. Measuring knowledge of recycled drinking water holds the potential to estimate how and whether educational interventions aimed at increasing acceptance of recycled drinking water programs work.

Paradigm shifts and current challenges in wastewater management

Wastewater is a significant environmental and public health concern which management is a constant challenge since antiquity. Wastewater research has increased exponentially over the last decades. This paper provides a global overview of the exponentially increasing wastewater research in order to identify current challenges and paradigm shifts. Besides households, hospitals and typical industries, other sources of wastewater appear due to emerging activities like hydraulic fracturing. While the composition of wastewater needs constant reassessment to identify contaminants of interest, the comprehensive chemical and toxicological analysis remains one of the main challenges in wastewater research. Moreover, recent changes in the public perception of wastewater has led to several paradigm shifts: i) water reuse considering wastewater as a water resource rather than a hazardous waste, ii) wastewater-based epidemiology considering wastewater as a source of information regarding the overall health of a population through the analysis of specific biomarkers, iii) circular economy through the implementation of treatment processes aiming at harvesting valuable components such as precious metals or producing valuable goods such as biofuel. However, wastewater research should also address social challenges such as the public acceptance of water reuse or the access to basic sanitation that is not available for nearly a third of the world population.

Responsible Water Reuse Needs an Interdisciplinary Approach to Balance Risks and Benefits

Freshwater is a precious resource, and shortages can lead to water stress, impacting agriculture, industry, and other sectors. Wastewater reuse is increasingly considered as an opportunity to meet the freshwater demand. Legislative frameworks are under development to support the responsible reuse of wastewater, i.e., to balance benefits and risks. In an evaluation of the proposed European regulation for water reuse, we concluded that the proposed regulation is not practically feasible, as the water provider alone is responsible for the risk assessment and management, even beyond their span of control. The required knowledge and resources are extensive. Therefore, without clear guidance for implementation, the regulation would hinder implementation of reuse programs. As a consequence, the current practice of uncontrolled, unintentional, and indirect reuse continues, including related risks and inefficiency. Therefore, we provide an outline of the interdisciplinary approach required to design and achieve safe, responsible water reuse. Responsible water reuse requires knowledge of water demand and availability, quality and health, technology, and governance for the various types of application. Through this paper we want to provide a starting point for an interdisciplinary agenda to compile and generate knowledge (databases), approaches, guidelines, case examples, codes of practice, and legislation to help bring responsible water reuse into practice.

Reactive Barriers for Renaturalization of Reclaimed Water during Soil Aquifer Treatment

Managed aquifer recharge (MAR) is known to increase available water quantity and to improve water quality. However, its implementation is hindered by the concern of polluting aquifers, which might lead to onerous treatment and regulatory requirements for the source water. These requirements might make MAR unsustainable both economically and energetically. To address these concerns, we tested reactive barriers laid at the bottom of infiltration basins to enhance water quality improvement during soil passage. The goal of the barriers was to (1) provide a range of sorption sites to favor the retention of chemical contaminants and pathogens; (2) favor the development of a sequence of redox states to promote the degradation of the most recalcitrant chemical contaminants; and (3) promote the growth of plants both to reduce clogging, and to supply organic carbon and sorption sites. We summarized our experience to show that the barriers did enhance the removal of organic pollutants of concern (e.g., pharmaceuticals and personal care products). However, the barriers did not increase the removal of pathogens beyond traditional MAR systems. We reviewed the literature to suggest improvements on the design of the system to improve pathogen attenuation and to address antibiotic resistance gene transfer.

Taking a Future Generation’s Perspective as a Facilitator of Insight Problem-Solving: Sustainable Water Supply Management

Human societies face various unsustainability problems, often characterized as “wicked” in the sense that they have no single definitive formulation. Thus, the role of creativity or insight in solving such problems has attracted a lot of attention from scholars. Therefore, this study investigated how an emerging methodology, Future Design (and its unique intervention of asking problem solvers to take a future generation’s perspective), can facilitate insight problem solving (IPS) and the generation of sustainable solutions. In a municipality in Japan, nine officers from a bureau responsible for water supply management participated in a series of seven Future Design workshops. In two groups, these officers created visions of water supply management 30 years into the future, taking the perspective of a future generation working in the same municipality. On the basis of in-depth transcription analyses of these workshops, we obtained a hypothetical framework demonstrating that four factors mediate the influence of perspective taking on IPS: (a) Discounting the present generation’s cost, (b) contrasting the future with the present, (c) deconstructing hierarchy, and (d) intellectual joy. While the first three mediators (a, b, and c) were considered to be contributors to the problem reframing and IPS via constraint relaxation, the fourth (d) was considered to do so via positive interpretation. Further, the reason why taking a future generation’s perspective is likely to lead to sustainable solutions, useful for the future—rather than the present—generation, is also discussed.

Enhancing domestic water conservation behaviour: A review of empirical studies on influencing tactics

The world faces imminent drought-related challenges that, from a tap-water supply perspective, require increasingly expensive infrastructure enhancement and energy expansion to maintain sufficient service levels. This paper argues that enhancing domestic water conservation provides a promising alternative or necessary addition to reduce costs and to stimulate pro-environmental behaviour. Although the number of field experiments on how people's behaviour can be changed with respect to their daily water consumption is growing, to date, most studies in this field have focussed either on explanatory socio-economic factors (e.g. water pricing, income, or family composition) or behavioural intentions and personal characteristics related to behavioural change. Accordingly, there is limited empirically validated knowledge about the use and effectiveness of different influencing tactics to change behaviour. This paper provides a review of the empirically oriented literature in this field and aims to provide an up-to-date assessment that identifies eight different Behavioural Influencing Tactics (BITs) that target long-term water conservation behaviour within households. Our analysis is structured around three information processing routes: the reflective route, the semi-reflective route, and the automatic route. We conclude that the current body of literature is promising and provides a useful body of evidence on the range and effectiveness of individual water conservation mechanisms, but that needs further development to deepen our understanding of how to effectively prolong and reinforce newly formed water conservation routines.

Techno-economic evaluation and comparison of PAC-MBR and ozonation-UV revamping for organic micro-pollutants removal from urban reclaimed wastewater

The presence of sewage-borne Organic Micro-Pollutants (OMP) in Wastewater Treatment Plants (WWTP) effluents represents an increasing concern when water is reclaimed for irrigation or even indirect potable reuse. During eighteen months, an innovative hybrid water reclamation scheme based on a Membrane Biological Reactor (MBR) enhanced with Powder Activated Carbon (PAC) was operated at pilot-scale (70 m³/d) in order to compare it with state-of-the art Wastewater Reclamation System (WWRS) also revamped with a final step of ozonation-UV. Removal of persistent OMP, water quality and treatment costs were evaluated and compared for the different treatment schemes. OMP removal efficiency results for the different schemes concluded that established technologies, such as physico-chemical and filtration systems as well as MBR, do not remove significantly (>15%) the most recalcitrant compounds. The upgrading of these two systems through the addition of ozonation-UV step and PAC dosing allowed improving average recalcitrant OMP removal to 85 ± 2 and 75 ± 5%, respectively. In term of costs, PAC-MBR represents an increase of 37% of costs regarding conventional systems but presents improvements of 50% reduction in space and water quality. On the other hand, ozonation requires up to a 15% increase of foot-print; nevertheless, represents lower costs and lower carbon footprint. Ozonation-UV seems to be the best option for upgrading existing facilities, while PAC-MBR should be considered when space represents a critical limitation and produced water is reused for high water quality purposes.

Risk-Yuck Factor Nexus in Reclaimed Wastewater for Irrigation: Comparing Farmers’ Attitudes and Public Perception

The successes and failures of water reuse schemes are shaped by complex interrelationships between technological, economic, and socio-political factors. However, it has long been recognized that the main challenges to more effective water management are largely social rather than technical. This article reviews the recent literature (2007–2017) to analyze driving factors associated with farmers’ concerns and public perception of reclaimed wastewater for irrigation. The aim of the paper is to synthetize how both environmental and health risks and the yuck factor could be addressed in order to promote mutual understanding between farmers and the public. Results show: (1) how farmers and the public perceive environmental and health risks in a similar way, (2) how the yuck factor is more noticeable for the public than farmers, and (3) how constructed wetlands, reclaimed water exchange consortiums, product certification, and direct site visits to water reuse infrastructure could be promoted in order to foster understanding between farmers and the public. The article concludes by providing key research questions for managers and public authorities relating to how to focus on the study of technical and social issues related to water reuse.

Reclaiming Suburbia: Differences in Local Identity and Public Perceptions of Potable Water Reuse

Urban water managers are increasingly interested in incorporating reclaimed water into drinking supplies, particularly in rapidly growing arid and semi-arid urban areas, such as the western United States. Northern Nevada is one location that is considering augmenting drinking water supplies with reclaimed water, a practice that is known as planned potable water reuse. Potable water reuse can expand water supply and reduce wastewater disposal. However, past studies have shown that the introduction of potable reclaimed water can be controversial and requires an understanding of public perceptions of the resource prior to implementation. This study explores the factors that influence whether or not respondents in northern Nevada express willingness to drink reclaimed water. We pay specific attention to the degree to which self-identification as an urban, suburban, or rural resident influences how people consider using treated wastewater for both potable and non-potable purposes. To address this, we conducted a survey to assess community perceptions of reclaimed water use and applications in northern Nevada in the spring of 2018. We find that years spent living in the home and a respondent being female are negative and significant predictors of being willing to drink reclaimed water, while having heard of reclaimed water before and self-identification as a suburban resident are positive and significant predictors. As the region becomes more developed, particularly in its growing suburbs, it is essential to understand the nature of the interests and concerns regarding water resources and the expanded use of reclaimed water.

Effects of Community Perceptions and Institutional Capacity on Smallholder Farmers’ Responses to Water Scarcity: Evidence from Arid Northwestern China

Community contextual factors including community perceptions and institutional capacity are among the key determinants in community-based water resource management. The Institutional Analysis and Development (IAD) framework proposed by Ostrom is commonly employed to examine the outcome of common-pool resource management including water resources. However, community perceptions typically examined in behavioral economics and comparative community analysis literature are rarely incorporated in institutional analysis studies. This study draws on the IAD framework to investigate smallholder farmer communities’ responses to water scarcity in arid northwestern China. Adopting alternating multiple regression and multivariate regression models, this study conducts an empirical analysis using farmer survey data. The results show that the perceptions of water scarcity promote community actions in coping with water shortage. The perception of production risks encourages overall community responses, as well as farming- and irrigation-related responses. Communities with a stronger institutional enforcement are more responsive in taking farming-, irrigation-, and infrastructure-related actions, as well as having better overall responses. The analysis also shows that community interactional capacities and socio-economic factors may influence community actions to mitigate and adapt to adverse effects of local water scarcity. Our findings provide insights for understanding social and institutional aspects of rural farming communities toward sustainable response decisions to overcome water scarcity challenges.

Upscaling Urban Recycled Water Schemes: An Analysis of the Presence of Required Governance Conditions in the City of Sabadell (Spain)

Cleaning wastewater and using it again for secondary purposes is a measure to address water scarcity in urban areas. However, upscaling of recycled water schemes is challenging, and little is known about the governance conditions which are required for this. This paper addresses this knowledge gap. Based on a review of governance literature we suggest that five governance conditions are necessary for a successful upscaling of recycled water schemes: (1) policy leadership, (2) policy coordination, (3) availability of financial resources, (4) awareness of a problem, and (5) the presence of a public forum. We applied these concepts in a case study on the upscaling of a recycled water scheme in Sabadell, Spain. We reviewed policy documents, conducted a set of 21 semi-structured interviews, and attended two policy meetings about the subject. Our results suggest that Sabadell meets the required conditions for upscaling reused water to a certain extent. However, a public forum is not well-developed. We discuss the implications of this and conclude with some suggestions for future research and some lessons for other cities that plan to upscale their recycled water schemes.

Feasible analysis of reusing flowback produced water in the operational performances of oil reservoirs

Water reuse is considered one of the most efficient and optimum ways in petroleum industries to address the water scarcity problem. The effluents which are made by the petroleum operations are supposed to be one of the hazardous materials when they are discharged to the environment. The objective of this study is to measure the volume of the required water for the operational performances of the studied oil field. To do this, the necessary water and the volume of provided treated water for the waterflooding, tertiary flooding, and hydraulic fracturing procedures are appropriately measured and by the utilization of photo-Fenton/flotation are administered to remove the oil droplets. According to the observational measurements, it is clarified that hydraulic fracturing has supplied approximately 93% of its required water by the treatment of flowback water and it virtually eliminated the necessity of fresh water from local or domestic water resources. Moreover, the total freshwater that has been saved in this oil field is investigated about 80% of the total required water for their performances. Consequently, the lower need of fresh water from local resources would reduce the unnecessary expenses to provide this volume of water and would save fresh water for about 2750 inhabitants for 1 year to overcome the issue of water scarcity in the world.

Potable Water Reuse through Advanced Membrane Technology

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

Research on Big Data Digging of Hot Topics about Recycled Water Use on Micro-Blog Based on Particle Swarm Optimization

The public’s acceptance level of recycled water use is a key factor that affects the popularization of this technology; therefore, it is critical to know the public’s attitude in order to make guiding policies effectively and scientifically. To examine the major focuses and hot topics among the public about recycled water use, one of the major platforms for social opinion in China, the micro blog, is used as a source to obtain data related to the topic. Through the “follow-be followed” and “forward-dialogue” behaviors, a network of discussion of recycled water use among micro-blog users has been constructed. Improved particle swarm optimization has been used to allow deep digging for key words. Ultimately, key words about the topic of have been clustered into three categories, namely, the popularization status of recycled water use, the main application, and the public’s attitude. The conclusion accurately describes the concerns of Chinese citizens regarding recycled water use, and has important significance for the popularization of this technology.