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The uneven distribution, scarcity, and pollution of water resources can significantly hinder socioeconomic development. A conceptual framework of Water Resources Endowment-Efficiency-Pressure-Response-Structure-Cycle (2EPRSC) was proposed, and 16 indicators were selected to establish the evaluation index system. Taking the five economic zones in the Sichuan Province of China as the research area, the genetic algorithm optimized entropy weighting method-cloud model was applied to determine the water security grades. Subsequently, the coupling coordination degree (CCD) model was established based on water security system (WSS)-SES to analyze the CCD. The results showed that (1) temperature and investment were the two indicators with more significant impacts on water security in Sichuan Province. (2) From 2012 to 2022, water security in Sichuan Province as a whole presented a decreasing and then increasing trend. (3) From 2012 to 2022, CCDs of the WSS-SES in Sichuan Province's economic zones were mostly at moderate imbalance, with the Chengdu Plain economic zone showing the highest CCD. Overall, the CCD scores across the economic zones were on an ascending trajectory. The study, grounded in the state of water security and CCD in Sichuan, can forge a scientific foundation for the sustainable development of WSS-SES. [ABSTRACT FROM AUTHOR]

This review explores our understanding of Cryptosporidium species and Giardia duodenalis distribution in Middle East and North African (MENA) water resources. Results emphasize that Cryptosporidium species (sp.) and G. duodenalis (oo)cysts are present in distinct categories of water in ten MENA countries. Cryptosporidium sp. proportional prevalence in the MENA region was 24.5% (95% CI 16.3-33.8), while G. duodenalis prevalence was 37.7% (95% CI 21.9-55.1). Raw wastewater and surface water were the water categories most significantly impacted. Both parasites were reported in the various types of MENA drinking waters. The most frequent species/genotypes reported were C. hominis, C. parvum, and G. duodenalis assemblage A. Despite the high prevalence of (oo)cysts reported, we should consider the absence of waterborne outbreaks. This indicates significant underestimation and underreporting of both parasites in MENA. Stakeholders should apply water contamination legislation to eradicate Cryptosporidium sp. and G. duodenalis (oo)cysts from water resources/categories. [ABSTRACT FROM AUTHOR]

The study assessed static management, i.e., without planned periodic maintenance of the storage (no sediment dredging) denoted as SC1, or with maintenance denoted as SC2. The second approach was dynamic management based on applying Real-Time Control (RTC) techniques to scenario SC1 and scenario SC2 denoted as RTC-1 and RTC-2, respectively. The dynamic management of the UCT dam with RTC-1 and RTC-2 approaches increase yield by 2.1 and 1.1 ml, respectively. Additionally, RTC-1 and RTC-2 approaches increase volumetric reliability by 5.3 and 2.5%, respectively, while maintaining the required level of service of a stormwater harvesting system. SC1 and SC2 results in water savings of up to 21.15 and 21.45 ZAR/kl, respectively, while RTC-1 and RTC-2 could save up to 19.35 and 19.45 ZAR/kl. Thus, static configurations results in water savings approximately 9% in comparison to RTC. In addition, static configurations harvested stormwater at a relatively lowest unit cost in comparison to RTC configurations. Notwithstanding this finding, the RTC system exhibits a great potential in reshaping the stormwater harvesting system to simultaneously deliver water conservation and stormwater management. HIGHLIGHTS Assessed the extent to which stormwater harvesting could contribute to ‘net zero’, i.e., transitioning the University of Cape Town toward a ‘water-sensitive precinct’.; Impact of planned periodic maintenance in enhancing harvested stormwater volume.; Benefit of Real-Time Control (RTC) in enhancing harvested stormwater volume;

The assessment of the rainwater harvesting (RWH) potential in Hosaena City from medium to large public buildings is the main objective of the study. ArcGIS with Google Earth Pro was used to calculate the rooftop area of the selected building, and RWH from each category of public buildings was evaluated by considering rooftop areas, monthly rainfall, and runoff coefficient. The result shows that the highest amount of rainwater was harvested from the City Administration building in August (197.1 m3), whereas the lowest was collected from the Health Center building in December (1.8 m3). Additionally, the contribution of RWH from individual public buildings for each month was evaluated, and its values ranged from 0.073 to 1.8%. The comparison shows that Wachemo University, Nigist Eleni Comprehensive Hospital, a technical and vocational institute, and teacher training center buildings, could have a significant potential for rainwater storage, ranging from 1.56 to 28.41%. This implies that, besides saving a noteworthy volume of potable water, the excess rainwater can be stored and utilized for the later dry months. As a result, it is recommended that rooftop RWH in Hosaena be the best source of the city's water supply system to reduce the current water supply shortage. HIGHLIGHTS Rainwater harvesting (RWH) is a suitable technology to store excess rainwater and utilize it for the later dry months.; Medium to large public buildings are the main rooftop area in the field for the RWH system.; Use of RWH technology should reduce the water supply–demand gap in the city.; A large amount of rainwater per month was harvested from City Administration public buildings.;

This study investigated non-revenue water (NRW) dynamics in Rwanda from 1 July 2014, to 30 June 2023, utilizing panel data and cross-sectional datasets. It aimed to assess progress towards achieving the government's target of 25% NRW. Through panel data analysis and machine learning models, it examined water supply variations, NRW levels, and associated risks across fiscal years and regions. The observed average NRW of 41.24% underscores the need for targeted interventions to meet the set target. Regional disparities, exemplified by Kigali City's water network's 38.61% average NRW compared to Nyagatare's 55.31%, emphasize the importance of tailored strategies. Machine learning models indicated low and inconsistent progress across networks. Notably, no single water supply managed to meet the target in more than 20% of the 36 quarters studied. Comparison with existing literature highlighted excessive NRW in Rwanda, aligning with global trends. Achieving the 25% NRW target requires region-specific approaches, necessitating infrastructure improvements, leak detection, and capacity building. The positive correlation between water loss risk and household access to improved water sources accentuated the complexity in NRW reduction efforts. This study contributes to understanding NRW dynamics and informs sustainable water management strategies tailored to Rwanda's context. HIGHLIGHTS Need for balancing NRW reduction and access to improved water sources.; NRW is a region-specific issue.; WASAC is progressing slowly in the attainment of the target NRW of 25%.; Need to leverage panel data analysis and machine learning algorithms to understand NRW.; Most instances of 25% NRW or below were uncertain (due to issues of overlaps identified in all NRW classes), thus the need for a specific investigation on them.;

Capacity development is at the core of water operators' partnerships (WOPs), which aim to enhance the capacities and performance of water and sanitation service providers. This study sought to understand the factors in a WOP that favour or hinder the start-up phase of WOP projects. Fifty interviews were performed with representatives of the lead, beneficiary and additional partners of 18 projects of the European Commission programme during the first year of the programme. The article finds that WOP projects represent a considerable challenge for the staff of water utilities as participating in such partnerships requires a skill set that is different from the skills required in their daily work activities. The findings also suggest that the facilitation of the WOP start-up can smoothen and accelerate the development of WOP projects. Moreover, the article argues that because of limited time and financial resources, WOP projects need to find a balance between prioritizing impacts that can be achieved using the variety of capacity strengthening approaches that are available. HIGHLIGHTS The article examines factors that influence the start-up of water operators' partnership (WOP) projects under a large WOP programme.; Ownership, top-level commitment and integration of the WOP project within the utility strategy and processes are crucial factors during the start-up phase.; Partnership practice needs to be learned.; Facilitation can play a positive role in smoothing the partnering of water operators.;

The effectiveness of an emergency water supply using private wells has been asserted theoretically but not evaluated in detail. This paper aims to consider the effectiveness and shortcomings of emergency water supply based on local wells and to support policy formulation regarding groundwater usage in the event of a disaster. In Kamisu City, Ibaraki Prefecture, Japan, not only public-operated formal water supply points using water trucks but also informal water supply points using private wells were open to address water outages following the Great East Japan Earthquake of 2011. This study clarified the pattern of appearance and spatial distribution of those points by combining information from local newspapers, Internet archives, and an original questionnaire survey. In addition, the function of informal water supply points was quantitatively evaluated using GIS by comparing cases with and without informal water supply points. Analysis revealed that informal water supply points expanded the size of the serviced population within a 500-m radius of the water supply points by 47%, compared with cases when only formal water supply points were available. However, well water was not necessarily suitable for drinking owing to quality issues. As a policy lesson, the importance of sharing well information is indicated. HIGHLIGHTS In emergency, informal water supply points (IWSPs) using private wells are superior to public ones in terms of service area and speed of availability.; In this case study, IWSPs expanded the size of the serviced population within a 500-m radius of water supply points by 47%.; Groundwater cannot always be potable owing to quality problems.; Information sharing on IWSPs could encourage the appearance of additional water providers.;

Non-revenue water due to pipe leakages presents a significant global challenge, impacting both the economy and environmental sustainability. The current approach to pipe management for water utilities in Sweden is mainly reactive; leaks are repaired when detected, sometimes with large costs if the leakage is extensive and critical. With this study, we want to focus on proactive pipe network management by using an Artificial Neural Network (ANN) model to estimate the probability of leakage in water pipes. The ANN model was trained on leaks that occurred over 10 years. A comparison with leaks reported after the training shows that the model succeeds in identifying groups of pipes with a higher leakage frequency. Evaluation of both new and historical leaks in four different water pipe networks in Sweden showed that a higher prediction value from the ANN model was linked to a higher occurrence of leakage. This indicates that the ANN model succeeds in identifying some of the combinations of attributes that lead to leakage. An evaluation of the input attributes in the ANN model found that the most important attributes for leakage prediction were pipe material, pipe age, adjacent problems on the pipe stretch, pipe length and pipe dimension. HIGHLIGHTS An ANN model for pipe status in four Swedish water utilities has been assessed.; The ANN model demonstrates effectiveness in predicting leakages.; There are clear relationships between prediction values and reported leakages.; The most important attributes for leakage prediction are material, age, adjacent problems, length, and dimension.; The ANN model can identify potential leakages and enable proactive maintenance strategies.;

Multi-objective optimization of water distribution networks (WDNs) is crucial for achieving a balance between cost, equity, and reliability. The present study conducts a comparative analysis, evaluating the effectiveness of four multi-objective optimization algorithms implemented within the EPANET framework for the optimal design of three distinct WDNs taken from the literature. The networks were optimized considering three objectives: maximizing network resilience, and uniformity coefficient (CU, a measure of uniformity), alongside minimizing the cost of the network. Further, multi-criteria decision-making (MCDM) analysis is carried out, encompassing various MCDM techniques and weighting methods, to explore the sensitivity of solution rankings. In Network 1, non-dominated sorting genetic algorithm 2 (NSGA-II) produced suboptimal solutions with CU and In values below 0.4, while caRamel, multi-objective particle swarm optimization based on crowding distance (MOPSO-CD), and multi-objective evolutionary algorithm with decomposition (MOEA/D) showcased increasing CU and In values towards 1, paralleled by a rise in network cost. The performance of NSGA-II in Network 3 was unsatisfactory (CU < 0.32), while the other algorithms demonstrated satisfactory values (>0.98) for reliability and (>0.5) for CU. The findings offer valuable insights into cost-effective strategies for achieving equity in water supply without substantial impact on overall network cost. The findings of the study also underscore the sensitivity of ranking outcomes in MCDM analysis to the choice of technique and weighting method. HIGHLIGHTS A multi-objective optimization model is developed for the design of an intermittent water supply system.; The equity in water supply and network resilience along with the cost for the optimal design is considered.; A comparative analysis of various multi-objective optimization algorithms for the design of WDNs is made.; Ranking of optimal solutions is made.; The sensitivity of the ranking by different MCDM techniques is explored.;

This study in Rwanda offers a comprehensive analysis of water quality, reliability, and cost-effectiveness, departing from previous research by utilizing panel data analysis for a nuanced understanding of spatiotemporal dynamics. Unlike earlier studies focusing on specific aspects, this research adopts a holistic approach, examining factors crucial for water supply, quality, and cost, thus providing an integrated view of Rwanda's water sector. By analyzing data from various sources, including the Water and Sanitation Corporation (WASAC), the study evaluates the reliability, quality, and cost-effectiveness of drinking water. It identifies cost-effective water treatment plants and studies determinants such as production cost, raw water quality, and supply between 2017 and 2022, introducing novel metrics such as performance scores and a drinking water quality index. Despite an increase in lost water, WASAC notably improves water supply, resulting in a higher water access rate by 2022. The study highlights the influence of factors such as performance scores and raw water quality on water supply and quality. It emphasizes continuous monitoring, targeted interventions, and community engagement for sustainable water service delivery. The findings provide actionable insights for policymakers, stakeholders, and practitioners, aiming to enhance water management strategies and improve water access in Rwanda. [ABSTRACT FROM AUTHOR]

Taking the Yangtze River Source Basin (YRSB) and Shule River Basin (SRB) as two typical cases, the sustainability of the water resources in these two basins was evaluated using the level of water stress (LWS) from sustainable development goal 6.4.2, and the regulating effect of the glacier runoff on the LWS was quantified. From 2000 to 2030, the level of socioeconomic development in the YRSB is low, and the total water consumption is only about 0.18 x 108 m3, whereas the SRB has a relatively high level of socioeconomic development and total water consumption is about 10 x 108 m3, i.e., 50 times higher than that in the YRSB. For the aforementioned reasons, the SRB's LWS is much higher than the YRSB's, resulting in a very low sustainability of water resources. As natural assets, glaciers flow downstream in the runoff mode, so compensation at the watershed scale should be considered. In the basin, the optimal allocation of water resources is needed. At the interbasin scale, the compensation mechanism of glacier water resources needs to be improved. [ABSTRACT FROM AUTHOR]

A new type of bio-composite material is being produced from water-recovered resources such as cellulose fibres from wastewater, calcite from the drinking water softening process, and grass and reed from waterboard sites. These raw materials may be contaminated with pathogens and chemicals such as Escherichia coli, heavy metals, and resin compounds. A novel risk assessment framework is proposed here, addressing human health risks during the production of new bio-composite materials. The developed framework consists of a combination of existing risk assessment methods and is based on three main steps: hazard identification, qualitative risk mapping, and quantitative risk assessment. The HAZOP and Event Tree Analysis methodologies were used for hazard identification and risk mapping stages. Then, human health risks were quantitatively assessed using quantitative chemical risk assessment, evaluating cancer and non-cancer risk, and quantitative microbial risk assessment. The deterministic and the stochastic approaches were performed for this purpose. The contamination of raw materials may pose human health concerns, resulting in cancer risk above the threshold. Microbial risk is also above the safety threshold. Additional analysis would be significant as future research to better assess the microbial risk in biocomposite production. The framework has been effectively used for chemical and microbial risk assessment. [ABSTRACT FROM AUTHOR]

The study objective is to analyze the water expenditure of 4315 rural households in the Karst region of China. The empirical results have been analyzed by using the extended linear expenditure system model. The study has been based on water expenditure, which provides a feasible differential water pricing strategy in the karst region of China. The result shows that (1) the coefficient for water expenditure has been examined as low. The coefficient of water expenditure in the Karst region ranges from 0.534 to 1.025%, the average value is 0.723%, and the modified coefficient ranges from 0.814 to 1.508%, with an average value of 1.070%. (2) The marginal consumption propensity of rural residents in the Karst region is 0.2%, and the marginal consumption propensity in each province ranges from 0.1 to 1%. (3) The per capita basic water demand has 3 m3. In this scenario, the study recommended that basic water prices range from CNY 2.091 to CNY 3.468 per cubic meter. If the water consumption exceeds basic demand (3 m3 per month), then the bearing water price shall not be lower than CNY 2.091 to CNY 3.468 per cubic meter and not higher than CNY 7.122 per cubic meter. HIGHLIGHTS Analyzed the water expenditure of 4,315 rural households in the Karst region of China.; The basic water prices range from CNY 2.091 to CNY 3.468 per cubic meter.; The water price reform in rural China should be subsidies and flexible.; Increasing financial subsidies for low-income households and charging discount fees to households with idle water equipment.; Water pricing mechanism should be flexible for everyone.;

Shared sanitation services continue to expand in India's growing cities, yet, these facilities are blighted by issues including lack of privacy, overflow of raw sewage, and notably, a lack of water supply. Access to water in shared toilets for menstruating women and girls to wash themselves, their reusable menstrual products, their stained clothes, and sanitation infrastructure is a critical but all too-often neglected aspect of menstrual hygiene management (MHM). Drawing on the existing literature and data from Maharashtra, this commentary article uses the example of urban India to highlight the ‘need of the hour’, the provision of water in shared sanitation facilities in the global South for MHM as and when required. Evidence-based water supply norms in shared sanitation for MHM, from menarche to the perimenopause, are key, to highlight the need for water as an ‘MHM plus’ requirement for women and girls reliant on shared facilities. Connecting shared toilets to piped water is a long-term process, but the provision of water in buckets is a start. Hygiene promotion can create awareness of the importance of water for sustainable MHM. Monitoring and evaluation can determine the impact of supplying water in shared toilets on MHM. HIGHLIGHTS Water supply is needed for menstrual hygiene management (MHM).; The supply of water for MHM is neglected in shared toilets.; Providing water in shared toilets can improve MHM and reproductive health, support women and girls dependent on community and public toilets, encourage sustainable MHM, and reduce menstrual waste.; Evidence-based water supply norms for MHM should support policymaking to provide water supply in shared sanitation services.;

Globally, surface water, groundwater, soil moisture, snow storage, canopy water, and wet biomass constituents make up water storage, which plays a significant role in the hydrological water balance. Evaluating the variations in water storage anomalies associated with climate forcing and human activities over river basins is crucial for assessing water scarcity and predicting potential pressures on water resources in the future. In this study, we assessed the impacts of climatic and anthropogenic drivers on the change in water storage in the river basins of Ethiopia by using the independent component analysis to examine Gravity Recovery and Climate Experiment with the Global Land Data Assimilate System-based water storage and comparing the independent component analysis with hydro-meteorological data and statistical data related to human activities. It is of great significance for helping people better understand the evaluation of terrestrial water storage anomalies under the combined influence of climatic change and anthropogenic activities and providing information for better protection and utilization of water resources at river basin level. It is crucial to take effective measures to protect these precious land and water resources and prevent their further deterioration. The estimated result will be essential for sustainable water management and protection. [ABSTRACT FROM AUTHOR]

Pacific Island Countries (PICs) collectively have the lowest rates of access to safely managed or basic drinking water and sanitation globally. They are also the least urbanised, have dynamic socioeconomic and increasing climate-linked challenges. Community-based water managers need to respond to variability in water availability and quality caused by a range of hazards. Water Safety Planning (WSP), a widely adopted approach to assessing water supply, offers a risk-based approach to mitigating both existing and future hazards. WSP is adaptable, and making modifications to prescribed WSP to adapt it to the local context is common practice. Within the Pacific Community Water Management Plus research project, we used formative research and co-development processes to understand existing local modifications, whether further modifications are required, and, to develop additional modifications to WSP in Fiji, Vanuatu and Solomon Islands. The types of additional local modifications we recommend reflect the unique context of PICs, including adjusting for community management of water supplies and required collective action, community governance systems, levels of social cohesion in communities, and preferred adult-learning pedagogies. Incorporating modifications that address these factors into future WSP will improve the likelihood of sustained and safe community water services in Pacific and similar contexts. [ABSTRACT FROM AUTHOR]

The available literature on natural hazard risk analysis focused on the implementation of water safety plans (WSPs) is surprisingly quite poor, despite the significant increase in the number and severity of disasters and adverse effects on drinking water supply systems generated by natural hazards. At the same time, WSPs that conveniently account for natural hazards with a comprehensive approach 'from source to tap' are still scarce as they typically occur at larger spatial scales and adequate prevention, mitigation and adaptation require efficient inter-institutional collaborations. The aim of this paper is to highlight the main bottlenecks for water utilities to include natural hazards in the development of their WSPs. The research adopted a stakeholders-oriented approach, involving a considerable number of water utilities (168), water sectoral agencies (15) and institutions (68) across the Adriatic-Ionian Region through a stepwise process that generated joint SWOT analysis, the development of a decision support system (DSS) focused on WSPs procedures and tabletop exercises. The final outcomes generated strategic documents (REWAS - Adrion Road map for resilient water supply) that highlighted the necessity for efficient cross-sectoral and inter-institutional cooperation in the development of well-founded and robust WSPs to address natural hazard risk analysis for water supply systems (DWSS). [ABSTRACT FROM AUTHOR]

In a recent monitoring study of Minnesota's public supply wells, Cryptosporidium was commonly detected with 40% of the wells having at least one detection. Risk factors for Cryptosporidium occurrence in drinking water supply wells, beyond surface water influence, remain poorly understood. To address this gap, physical and chemical factors were assessed as potential predictors of Cryptosporidium occurrence in 135 public supply wells in Minnesota. Univariable analysis, regression techniques, and classification trees were used to analyze the data. Many variables were identified as significant risk factors in univariable analysis and several remained significant throughout the succeeding analysis techniques. These factors fell into general categories of well use and construction, aquifer characteristics, and connectedness to the land surface, well capture zones, and land use therein, existence of potential contaminant sources within 200-feet of the well, and variability in the chemical and isotopic parameters measured during the study. These risk categories, and the specific variables and threshold values we have identified, can help guide future research on factors influencing Cryptosporidium contamination of wells and can be used by environmental health programs to develop risk-based sampling plans and design interventions that reduce associated health risks. [ABSTRACT FROM AUTHOR]

Onsite wastewater treatment systems (OWTSs) and private wells are commonly used in Eastern North Carolina, USA. Water from private wells is not required to be tested after the initial startup, and thus persons using these wells may experience negative health outcomes if their water is contaminated with waste-related pollutants including bacteria, nitrate or synthetic chemicals such as hexafluoropropylne oxide dimer acid and its ammonium salt (GenX). Water samples from 18 sites with OWTSs and groundwater wells were collected for nitrate, Escherichia coli (E. coli), total coliform, and GenX concentration analyses. Results showed that none of the 18 water supplies were positive for E. coli, nitrate concentrations were all below the maximum contaminant level of 10 mg L-1, and one well had 1 MPN 100 mL-1 of total coliform. However, GenX was detected in wastewater collected from all 18 septic tanks and 22% of the water supplies tested had concentrations that exceeded the health advisory levels for GenX. Water supplies with low concentrations of traditionally tested for pollutants (nitrate, E. coli) may still pose health risks due to elevated concentrations of emerging contaminants like GenX and thus more comprehensive and routine water testing is suggested for this and similar persistent compounds. [ABSTRACT FROM AUTHOR]

Acque Bresciane is a public company that manages the integrated water cycle for more than 580,000 inhabitants in the Province of Brescia, in the north of Italy, providing drinking water, waste water treatment, and sewer systems. Drinking water systems are supplied with different types of groundwater, springs, and surface water sources (from lakes and rivers) whose availability and quality can be affected by climate change events. A multidisciplinary team, in collaboration with the University of Milano Bicocca, developed a specific Water Safety Plan (WSP) risk matrix focusing on the evaluation of climate-related hazardous events and calculation of their likelihood of occurrence, also using thematic maps. Moreover, to reduce the residual risks, in the risk matrix, possible control measures are suggested, such as the activation of an emergency plan, the use of other water sources, storage tanks, and interconnection with other water distribution networks. This work shows a simple and effective tool that can be applied by drinking water utilities to evaluate climate-related catchment risks, using a WSP risk matrix, thematic maps, and possible control measures to reduce risks in terms of water quality and availability and to respond with resilience to changes. [ABSTRACT FROM AUTHOR]

The world grapples with immediate crises like COVID-19, Russia's invasion of Ukraine, floods, droughts and wildfires. However, a longer-term crisis looms due to humanity's overstepping of planetary boundaries and its disruptive consequences. Growing awareness of the potential collapse of societies due to planetary boundary violations has prompted increased attention in the scientific literature. In the water sector, where infrastructure built today might persist during a future collapse, we must therefore ask ourselves how a (basic) level of water supply can be maintained in a collapsing society. This paper explores this question and proposes research directions to address it in the short to medium term. Despite the seeming remoteness of a societal collapse scenario, it is imperative to incorporate it urgently into water infrastructure research and planning. HIGHLIGHTS Environmentally induced societal collapse is an ignored risk for the water sector.; Research into potential consequences and strategies for deep adaptation are needed.; A four-stranded approach for this research is proposed, mirroring a prior one for research on worst-case climate change and systemic risks.;

To ensure universal access to water supply and sanitation (WSS) services that are safe, reliable, sustainable, and affordable, it is important to attract the right types of financing and identify the aspects that could be hindering the success of WSS projects. In this study, 62 completed World Bank WSS projects were analyzed to understand the relationship between project characteristics, bank performance, and quality of results. The methodological approach included a systematic quantitative review and comparative, statistical, and regression analyses, considering important aspects of the projects. The existence of correlations and interactions between project results, bank performance, and key aspects of the projects (such as type of project, initial and final risk assessments, commitments and disbursements, and other characteristics) was observed. This study highlights the importance of rating and mitigating WSS project risks (especially the environmental, social, political, and governance risks) and the importance of development bank financing. The applied methodology could be used by both financiers and borrowers. HIGHLIGHTS The study highlights the importance of assessing and mitigating risks, especially the environmental, social, political, and governance risks.; The rating of project risks appears to be a worthwhile procedure that could be adopted by financiers and borrowers alike.; Development bank financing is important for the quality of WSS project results.;

The gap between water supply and demand is increasing in several urban clusters of the world. This study uses the water evaluation and planning model to assess the water supply and demand dynamics in one of the large metropolitan regions of the Chennai hydrological basin. The primary water supply sources, including reservoirs, groundwater, inter-basin transfer, and desalination plants, were integrated into the model to simulate the current and future water demand and supply scenario. Three rainfall scenarios (excess, normal, and deficit) were utilized to assess their impacts on water supply. The study highlights the increase in unmet demand for normal and deficit rainfall scenarios. In response, various mitigation options were explored, including increasing groundwater recharge, reservoir capacity enhancement, water treatment plant expansion, additional storage, and utilization of water stored in rock quarries. The findings provide valuable insights for policymakers and stakeholders to develop sustainable water management strategies in the Chennai Basin. HIGHLIGHTS Water supply-demand gap keeps increasing in Chennai Basin, highlighting the need for proactive planning and efficient management.; Expanding desalination plants, increasing water treatment capacity, and increasing reservoir capacity through desilting and utilizing quarries can enhance water availability.; Groundwater recharge measures and alternative measures are crucial to bridge the supply-demand gap in the Chennai Basin.;

A risk-based approach is recognised worldwide as the most reliable means for the provision of safe drinking water. Efficient implementation of the water safety plan (WSP) approach, recommended by the World Health Organization (WHO), is facilitated by an auditing framework. In Hungary, development of WSPs is a legal obligation for water suppliers. WSPs are subject to a two-stage regulatory audit, a consultative central technical audit and a formal local audit. In 2019, a survey was conducted in cooperation with WHO to evaluate audit experiences of over 1,200 WSPs. Recommendations from the central audit significantly improved coherence and compliance of WSPs, confirming the efficiency of the dual approach. The use of a WSP template provided by the national authority further increased consistency and reduced time and work demand of the audit. Both water suppliers and public health authorities indicated a need for further capacity building on WSP development and auditing. The main challenge for water suppliers is the identification and risk assessment of hazards associated with the water source and distribution within premises. The recast European Union drinking water regulation is expected to accelerate the uptake of WSP and strengthen linkages to water catchment management and water safety in buildings. HIGHLIGHTS Experiences of a dual regulatory water safety plan auditing system were evaluated.; Survey addressed audit outcomes of over 1,200 WSPs.; Central (national) audit ensures consistent high quality of WSPs.; Local regulatory audit complements with in-depth local knowledge and on-site visit.; Regular trainings are essential both for water supply operators and authorities.;

This article compares the concentration levels of 17β-estradiol (E2), bisphenol-A (BPA) and caffeine (CAF) in the Sinos River, Brazil, which is a source of drinking water and the presence of contaminants after the conventional treatment in a municipal water treatment plant (WTP). A total of nine sampling campaigns were carried out, with sample collection in the Sinos River, upstream and downstream of the WTP, in addition to a drinking water sample (DW). The samples were extracted with solid phase extraction (SPE) and the concentration by liquid chromatography coupled to mass spectrometry (LC-MS). The maximum concentration in the Sinos River was 6,127.99 ng·L−1 for E2, 3,294.63 ng·L−1 for BPA and 1,221.95 ng·L−1 for CAF. In drinking water, the concentration range of E2, BPA and CAF was from less than the Detection Limit (DL) up to 437.50 ng·L−1,

The assessment of sprinkler system performance is crucial in ensuring the efficient use of water resources. The commonly used indicators of the uniformity of water distribution in sprinkler systems are Christiansen's uniformity (CU) and distribution uniformity (DU) coefficients. A more comprehensive analysis of water distribution is essential in situations where the reliability of these coefficients as indicators of water distribution patterns is limited. In the present research, distribution maps of water depth were prepared from water application profiles using catch cans experiments that were carried out in the research farm of the Agriculture and Natural Resources Faculty of the University of Tehran, which is located in Alborz province. In this way, water application profile data were obtained at different operating pressures (200, 250, 300, 350, and 400 kPa). By using this data, 2D and 3D distribution maps of water depth were created due to the overlapping of sprinklers in different arrangements, spacing, and pressures. In addition, CU and DU coefficients in square, rectangular, and triangular arrangements with different spacing and pressures from 200 to 400 kPa. A total of 11,250 different simulations were calculated and analyzed. Distribution maps of water depth contribute to advancing the understanding of sprinkler irrigation system performance and aid in the optimization of water management practices. HIGHLIGHTS CU and DU coefficients provide only an overall measure of uniformity and do not demonstrate the spatial variability of water depth, which could lead to over- or under-irrigation in certain areas of the field.; Water depth distribution maps offer a more accurate assessment of spatial variability and allow for the identification of specific areas that require attention to improve sprinkler system performance.;

Water supply from a common pool resource based on productivity indicators for different uses is one of the goals of planning in dry areas. Productivity indicators are defined based on time, geographical location and hydrological conditions in the form of food security, economic benefits and ecosystem restoration. This study was conducted in order to evaluate the contrast between economic criteria and food security in the exploitation of water resources in Lu'an city in Anhui province of China. Probabilistic modeling based on the prediction of uncertain values using the Latin hypercube technique was used for hydrological variables and water resources. The method of data mining and trend analysis of dependent variables was also simulated to estimate economic values in the water cycle. Statistical information of 32 years from 1991 to 2022 has been collected and used as an annual average per population. The results showed that the economic value of water consumption in the tourism industry has increased compared to agriculture. The total water provided for food security is equal to 6.5 m3 per person, the excess of which can be allocated to other uses through weighting indicators based on ecosystem and quality. HIGHLIGHTS The bargaining approach in water supply between the two beneficiaries of agriculture and tourism has been evaluated.; The results showed that the increase in water permits in the tourism industry has increased the economic value of water allocation.; The bargaining model showed that the weight of food security is more in the desirable functions of the ecosystem.;

Adequate and sustainable supply of potable water in urban areas of developing countries is often a challenge. This study assessed the performance of the water supply system in Muke Turi town, Oromia, Ethiopia. The Water Geospatial Engineering Modeling System (WaterGEMS) model was used for hydraulic analysis of the distribution network. The water losses were determined by different indicators including non-revenue water (NRW), losses per pipe connection (LPC), losses per main pipe length (LMPL), unavoidable annual real losses (UARL), and infrastructure leakage index (ILI). The water supply coverage of the town was found as 43.34%, which is considerably low. From the hydraulic analysis, the velocity of flow in 54.2% of the pipe and pressure at 60% of the nodes were found within the recommended ranges. The NRW was estimated at 37.61%, which is above the acceptable limit. Of which, the real losses are the major ones with 37.14%. Moreover, the LPC and LMPL were found to be 298 l/d and 29,709 l/km/d, respectively, which are again above the recommended limits. Based on ILI, the annual real losses were estimated to be 4.31 times the UARL. Finally, it was concluded that access to water in the town is inadequate which is exacerbated by high losses. HIGHLIGHTS The level of performance of Muke Turi Town water supply system was assessed.; WaterGEMS hydraulic model was employed to simulate the water distribution network.; The water supply coverage and hydraulic performance of the system were found low.; The supply–demand gap and the water losses are high.; To improve the performance of the system, equitable distribution, service management, and control of losses need utmost attention.;

Determining sources of uncertainty in the agricultural water supply helps to increase irrigation scheduling accuracy. Evaporation and transpiration, sensitivity coefficient of water tension, cultivation costs, product price and water allocated to plants are among the main sources of uncertainty in the simulation process. This study was conducted to estimate the fluctuations of the response due to the uncertainty of four parameters of soil moisture, water provided for cultivation, cost of cultivation during the growing season, and coefficient of sensitivity to drought. In the concept of water and food nexus, two basic factors, including increasing economic productivity and achieving maximum product production, are known as decision criteria. Therefore, mathematical modeling of net income and the ratio of actual and potential yield production has been prepared according to the four uncertain input variables of the problem. The proposed model has used a multi-objective particle swarm optimization algorithm to estimate the best values of non-deterministic variables. The results of the uncertainty analysis showed that the range of changes in performance and net profit compared to the coefficient of sensitivity to water stress has different ranges and mechanisms and knowing the nature of each helps to improve the responses. HIGHLIGHTS The fluctuations of the response due to the uncertainty of four parameters of soil moisture, water provided for cultivation, and cultivation cost were evaluated.; Mathematical modeling of net income and the ratio of actual and potential yield production has been prepared according to the four uncertain input variables.;

Since their incorporation into the 2004 version of the World Health Organization's (WHO's) Guidelines for Drinking Water Quality (GDWQ), Water Safety Plans (WSPs) continue to be the pre-eminent process for the delivery of safe drinking water to consumers. WSPs achieve this by prioritising proactive, rather than reactive, management of risks to drinking water quality. Since the use of WSPs was incorporated into the GDWQ, a range of supporting resources have been produced to assist water suppliers in preparing WSPs. Producing a robust WSP is an important first step in the management of risk, but in many cases, the implementation of WSPs presents significant challenges, particularly in relation to the implementation of Module 5 (implementing improvements) and Module 6 (monitoring of control measures). To address barriers to WSP implementation, the Ghana Water Company Limited (GWCL), in a peer-to-peer partnership with two Australian water utilities, developed a pilot WSP implementation strategy for one of the company's drinking water supply systems. One of the outputs of the collaboration was the development of a framework for operationalising water safety planning, which incorporates basic guidance for embedding the WSP within routine operations, in order to ensure the safe management of drinking water. [ABSTRACT FROM AUTHOR]

Small water supplies face similar problems worldwide, regardless of ownership or management type. Non-compliance with water quality regulations is more frequent in small supplies than in large ones, as are waterborne disease outbreaks. The new European Union Drinking Water Directive requires risk-based approach (RBA) to secure water safety as is recommended in the World Health Organization's Guidelines for drinking water quality through 'water safety plans'. This is already in regulation in the Nordic countries, although less used in small supplies. In this research, we explore the challenges, barriers and possible solutions to implementing RBA and improving compliance in small supplies. This was achieved by conducting and analysing interviews with 53 stakeholders from all eight Nordic countries to produce recommendations for action by the different implicated actors. Our findings suggest the centrality of governmental policy, including support for continuous training, provision of simple RBA guidelines and increasing cooperation in the water sector. The Nordic experience reflects global challenges with small water supplies and the trend towards systematic preventive management epitomized in the framework for drinking water safety advocated by the World Health Organization since 2004. [ABSTRACT FROM AUTHOR]

Access to freshwater resources has become more limited. Correspondingly, water monitoring methods in sensitive or critical areas interims of terrestrial water storage are becoming increasingly important. The monitoring of the water storage in this area, using appropriate methods and datasets, is highly effective in preventing possible future water crises. This paper aims to estimate terrestrial water storage of the Abbay River Basin with available data and tools where hydro climatological studies are scarce due to limited observation. The data obtained from Global Land Assimilation System (GLDAS), gravity recovery and climate experiment (GRACE), and TerraClimate were used for the analysis of terrestrial water storage in the river basin. The result shows that there was a varying trend of terrestrial water storage for the study time. We have observed water shortages during the dry season and surplus water during the wet season. The monitoring of changes in terrestrial water storage is crucial for optimal water resource utilization and our results confirm the major role of such monitoring in decisionmaking processes and management. [ABSTRACT FROM AUTHOR]

This article compares the concentration levels of 17β-estradiol (E2), bisphenol-A (BPA) and caffeine (CAF) in the Sinos River, Brazil, which is a source of drinking water and the presence of contaminants after the conventional treatment in a municipal water treatment plant (WTP). A total of nine sampling campaigns were carried out, with sample collection in the Sinos River, upstream and downstream of the WTP, in addition to a drinking water sample (DW). The samples were extracted with solid phase extraction (SPE) and the concentration by liquid chromatography coupled to mass spectrometry (LC-MS). The maximum concentration in the Sinos River was 6,127.99 ng·L−1 for E2, 3,294.63 ng·L−1 for BPA and 1,221.95 ng·L−1 for CAF. In drinking water, the concentration range of E2, BPA and CAF was from less than the Detection Limit (DL) up to 437.50 ng·L−1,

A risk-based approach is recognised worldwide as the most reliable means for the provision of safe drinking water. Efficient implementation of the water safety plan (WSP) approach, recommended by the World Health Organization (WHO), is facilitated by an auditing framework. In Hungary, development of WSPs is a legal obligation for water suppliers. WSPs are subject to a two-stage regulatory audit, a consultative cen- tral technical audit and a formal local audit. In 2019, a survey was conducted in cooperation with WHO to evaluate audit experiences of over 1,200 WSPs. Recommendations from the central audit significantly improved coherence and compliance of WSPs, confirming the efficiency of the dual approach. The use of a WSP template provided by the national authority further increased consistency and reduced time and work demand of the audit. Both water suppliers and public health authorities indicated a need for further capacity building on WSP development and auditing. The main challenge for water suppliers is the identification and risk assessment of hazards associated with the water source and distribution within premises. The recast European Union drinking water regulation is expected to accelerate the uptake of WSP and strengthen linkages to water catchment management and water safety in buildings. [ABSTRACT FROM AUTHOR]

The formation of ice jams is sudden, and they will cause abnormal water level fluctuations in water diversion projects, affecting the water supply and even causing severe flood disasters. Based on the characteristics of the Middle Route of the South-to-North Water Diversion Project, this paper uses the numerical simulation method to establish an emergency intervention effect simulation model for ice jam events. The hydraulic response characteristics of the project under gate group scheduling and taking different emergency measures are analyzed with the water level deviation and stabilization time consumption of the pool as indicators. Moreover, this paper proposes an emergency intervention mode for ice jam events. The results show that using the gate group scheduling after ice jam events will cause a sharp rise in the upstream water level of the pool where the ice jams are located. Also, compared with other emergency measures, the electric heating ice melting measure has less influence on water level, and the de-icing effect is better. Finally, the emergency intervention mode can signifi- cantly reduce the maximum water level deviation and shorten the time required to stabilize the water level. [ABSTRACT FROM AUTHOR]

The establishment of national strategic frameworks for systematic scaling-up of water safety plans (WSPs) implementation needs to overcome major constraints: lack of legislation and policies, and the need for appropriate monitoring tools. In 2018, the Uruguayan regulator for energy and water services promulgated a regulation intended to ensure an ambitious and pragmatic strategy that supports and promotes WSP implementation and auditing at a national scale. The goal is to have all drinking water supply systems with their WSP implemented by 2030. For this, a demanding schedule was recommended considering the size of the drinking water supplies: (i) large systems serving more than 2,000 inhabitants and (ii) small and very small systems serving fewer than 2,000 inhabitants. A mandatory verification through internal and external audits was also established. This work describes the legal and regulatory framework as well as the challenges and opportunities that open up for the generalization of WSP implementation in Uruguay. Despite the impact of COVID-19 on working conditions for water suppliers, as for the year 2022, WSPs have been successfully implemented in 94 water systems serving more than 2.4 million people. Results of successful implementation and auditing processes are presented and discussed covering methods and outcomes. [ABSTRACT FROM AUTHOR]

Improved water, sanitation and hygiene (WASH) facilities in water-scarce areas is one of the most important barriers to improving the standards of people’s life, which is even worse in a locality with forcibly displaced people (e.g., nearly 1 million Rohingya refugees in Bangladesh). In attempting to understand the extent of vulnerability and risks of WASH facilities, their impacts, and adaptive practices in the communities, an exploratory study has been carried out in five selected camps (13, 15, 16, 24 and 27) in Cox’s Bazar, Bangladesh. Examination of water facilities shows that households in camps 13, 15 and 16 suffered from an adequate supply of water during summer as there is no direct access to surface water from adjacent water reservoirs, while camps 24 and 27 have such facilities. The frequency of water shortage for drinking purposes in camps 13, 15 and 16 was not so severe as in camps 24 and 27. Drinking water collectors had to spend 3–5 h in queues. All latrines were communal/shared latrines, which made users feel uncomfortable and vulnerable. This study implies that WASH facilities need to be reinforced, and community sensitization on WASH behavior needs to be strengthened to reduce WASH-related health hazards. [ABSTRACT FROM AUTHOR]

To have an efficient water distribution network, optimal design alternatives need to be identified and analysed using combined hydraulic modelling and optimization. This paper reports on the application of the fast-messy genetic algorithm (fmGA) coupled with hydraulic modelling tool EPANET to assess and select an optimum design and operational alternative for a water distribution pipe network. The sole objective of the optimization modelling was to minimize network costs subject to hydraulic and design constraints. The fmGA was first tested using the benchmark case study of the Hanoi network and then applied to the real network of Maun, Botswana which is considered as the case study. We have compared our results of the fmGA model application with other optimization techniques applied to the Hanoi network. The findings of the test revealed that the fmGA is superior to other popular metaheuristic optimization methods in terms of processing speed with comparable accuracy and pressure constraints fulfilled for all nodes. It also provides the best solution. For the water distribution network of Maun, the best pipeline configuration and route were determined, in which Configuration B is found to be the best and least cost solution to improve the water supply situation in Maun. HIGHLIGHTS A combined hydraulic modelling and optimization modelling has been employed to enable the design of an efficient water distribution network, where optimal design alternatives are identified and analysed.; This paper employs the fast-messy genetic algorithm (fmGA) coupled with the hydraulic modelling tool EPANET to assess and select an optimum design and operational alternative for a water distribution pipe network.;

The purpose of this research is to investigate the climate change impacts in Maroon Basin, Iran. To investigate the impacts of climate change on rainfall, temperature, and inflow in Maroon Dam, a simulation of four general circulation models (GCMs) was done in three future periods 2021–2040, 2041–2060, and 2061–2080. The results showed that the projected increased temperature would significantly reduce the runoff in the basin, despite the projected increase in rainfall. The most significant decrease of the average inflow to the Maroon Dam Reservoir in the near future of the RCP4.5 and RCP8.5 scenarios in March 24 and 26.4%, the middle future in March 25.4 and 29%, and the far future in March 27 and 30.6%, respectively, is predicted. Also, the MODSIM model simulation results showed that the Maroon Dam Reservoir would face a water resources shortage in the future to provide maximum demands. The average water supply reliability in climate change scenarios showed that the maximum water supply of 85% in the period 2021–2040 and the minimum of 80.4% in 2061–2080 would occur in the RCP4.5 and RCP8.5 scenarios, respectively. HIGHLIGHTS To plan for water resources allocation to demands in the Maroon Basin affected by climate change, a combination of SWAT and MODSIM models was used.; It was found that the RCP8.5 scenario will have the most severe water stress and the worst allocation conditions.; Add-on of a water management model to a hydrological model results in a powerful simulation tool that can serve for sustainable river basin management.;

Water supply is a crucial concern for planners across all countries, especially in rural communities. This paper proposes a multidimensional approach to examining the effective criteria for water supply projects in rural areas of Iran. The study compares alternative methods of project implementation and employs three multi-criteria decision-making (MCDM) methods: analytical hierarchy process (AHP), Fuzzy-AHP, and technique for order preference by similarity to ideal solution (TOPSIS) to prioritize criteria, sub-criteria, and alternatives. The results indicate that, among the five options analyzed, diverting water from the river and constructing temporary storage dams are the highest priorities, while pipeline branching to the nearby city or village is given the lowest priority. The study reveals that environmental and economic criteria are more critical than social-security and technical-management criteria, while negative environmental impacts and the possibility of risk-taking by subversive agents are the most important among the 14 sub-criteria studied. HIGHLIGHTS The most important criteria and sub-criteria in the implementation of rural water supply (RWS) projects are prioritized.; The fuzzy framework and TOPSIS techniques are integrated into the AHP approach to dissect different RWS choices.; The results indicate the great importance of environmental and economic criteria.; Technical-management and social-security criteria play a secondary role.;

Water supply and sanitation development in developing countries, specifically in Ethiopia, appear to be making substantial progress. Governments, international organizations, and other organizations are contributing to the development of water supply and sanitation systems. Water supply and sanitation challenges are linked to climate change effects and the quest for climate-resilient development. This paper evaluates the current challenges in water supply and sanitation development in developing countries and infrastructure resilience. The research is based on the data collected throughout the practical development task. Some of the findings were the climate change effect and temporary adaptation mechanisms, such as intermittent supply causing further pressure variation and water loss in the system. Resilient water supply and sanitation development require an integrated approach based on practical experiences, the latest technological development in water supply and sanitation system operation and management tools, and climate change adaptation. A seamless understanding of engineering, management, and technology is required for the development and management of water supply and sanitation systems. Dispersed skills may be available that were not effective at this time, which calls for a different approach to training provision and skill development as a package on design, management, and recent technological support. HIGHLIGHTS Challenges in water supply and sanitation development in developing countries.; Improved development needs pervious skills, recent technology, climate change, and resilience.; Adaptations as a temporary solution to climate change in water supply system that makes water distribution systems inefficient.;

In maize fields, few studies have been conducted to identify the temporal trend of soil salinity and formulate optimal irrigation plans under climate change. Therefore, the main goals of this study were to predict changes in soil salinity over 2022–2050 and to formulate an optimal supplemental irrigation plan preventing soil salinity in a South African rainfed maize field. The study used the Global Climate Model (GCM) MPI-ESM1-2-LR to obtain future climate data for the study area from 2022 to 2050 and applied the HYDRUS-1D model to project the effects of these future climate data on soil salinity over the same period and to identify the best irrigation plan under climate change. Two key findings were revealed: first, the combined use of GCMs (i.e., MPI-ESM1-2-LR model) and soil-water models (i.e., HYDRUS-1D) was a powerful tool to identify soil salinity trends and formulate optimal irrigation plan under climate change. Second, in addition to rainfall amount, supplying a limited supplemental irrigation amount equal to 8% of the actual evapotranspiration of maize at the mid-season stage of maize growth can significantly reduce soil salinity (

Many cities around the world face water crisis. Poor management contributes more to water crises than resource constraints. Multiple Indian metropolitan cities face severe water crises. These cities usually have high non-revenue water (NRW) levels. The present study estimates the efficiency of the extent of NRW management to improve per capita water supply (PCS) and cost recovery (CR) in 55 Indian metropolises with more than one million population. The study considered variable-returns-to-scale data envelopment analysis (DEA) using input orientation (I/P DEA). NRW has been used as the input variable, while the PCS and CR are studied as the output variables. The DEA model recommends that reduced NRW levels can address the water crisis in Indian cities. According to the DEA findings, about 38 Indian cities (68.09%) could reduce NRW levels by more than 50% while improving PCS and CR levels substantially. Around 47 cities (85.45%) can fulfil the water supply benchmark value of 135 litres per capita per day (lpcd). Three cities can improve the cost recovery by more than 100%. The findings suggest that water supply utilities in Indian cities should focus on reducing NRW levels substantially to improve the PCS and CR. HIGHLIGHTS Limited water resources and poor water management result in the water crisis in urban areas.; Indian metropolitan cities face water scarcity and usually import water from vast distances.; The study examines the efficiency of non-revenue water (NRW) to address cost recovery and a per capita water supply input-oriented DEA model was used.; Cautious management of NRW is helpful in reducing burden on utilities to augment new water sources.;

This paper presents updated water handpump functionality estimates for eight councils in the Mvila Division, southern region of Cameroon. The methodological approach was based on a technical inspection of 647 water points (181 boreholes and 466 wells) and semi-structured interviews with 500 stakeholders, including 103 water point committee members, 389 water users, and 8 water experts. According to the findings, one out of every three hand pumps is inoperable. Based on this rate, approximately 1.3 billion CFA francs (approximately 2 million US dollars) invested by the government, communities, and development partners are immobilized and do not generate any benefit for affected rural communities. This high level of handpump non-functionality is due to the low economic viability of water point management, the poor functionality of water point committees, and the poorly structured handpump maintenance chain. The pooling of water point management at the scale of the Mvila Division appears to be an avenue to be explored to improve the functionality of the handpump. HIGHLIGHTS This paper presents updated water handpump functionality estimates for eight councils in the Mvila Division, southern region of Cameroon.; Results show that one out of three handpumps is non-functional.; The factors that influence the functionality of handpumps are economic, institutional, managerial, and technical.;