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Abstract The critical importance of water makes it an indispensable natural resource. In context of urban infrastructure, particularly in the developing world, supplying water to urban households poses a notable challenge. Optimizing water supply systems (WSS) is one of the most arduous challenges in addressing this issue, primary contributors being energy and water losses during supply process. This paper focuses on the method adopted for minimizing losses in WSSs and creating a self-sustainable model for water supply in the urban settlement of Dehradun, India. The solution entails deployment of Energy Savings Companies (ESCO) service delivery model and the utilization of Supervisory Control and Data Acquisition (SCADA) system. This approach, thus far has yielded saving in both revenue, energy and water consumption at source, potentially generating saving that would enable covering the operational and maintenance changes for the established system for around 10 years.

The critical importance of water makes it an indispensable natural resource. In context of urban infrastructure, particularly in the developing world, supplying water to urban households poses a notable challenge. Optimizing water supply systems (WSS) is one of the most arduous challenges in addressing this issue, primary contributors being energy and water losses during supply process. This paper focuses on the method adopted for minimizing losses in WSSs and creating a self-sustainable model for water supply in the urban settlement of Dehradun, India. The solution entails deployment of Energy Savings Companies (ESCO) service delivery model and the utilization of Supervisory Control and Data Acquisition (SCADA) system. This approach, thus far has yielded saving in both revenue, energy and water consumption at source, potentially generating saving that would enable covering the operational and maintenance changes for the established system for around 10 years. [ABSTRACT FROM AUTHOR]

Water is essential for all human activities and for sustenance of human life. Adequate water supply to households remains a mirage due to poor water management leading to water wastages emanating from both the production and distribution process and the activities of water thieves and carelessness from inability of the SWAs to promptly resolve all reported cases of leaks and bursts in the distribution and production channels. This study has analyzed the ways through which water is lost from Water Distribution Production System and network and how it affects the revenue of PSWB. It utilized the authors' observations, key stakeholder interview and documented reports of leaks and bursts, illegal connections, administrative leakages and other non-revenue water obtained from Plateau State Water Board Jos. The study has established among other things that of all the leakages are as result of administrative and physical leakages, followed by vanadalisation and illegal connections which are more prevalent in Jos Central and Gada Biyu in Jos North and Bukuru/Rahol kanang area in Jos South Local Government Area, it also found that water losses impacts negatively on the revenue profile of the Board. The study concludes that water supply assets such as assessment pipelines networks to identify aged pipes where water leakages is common, prepaid water meters should be deployed to all areas to ascertain the actual volume of water delivered in the Water Distribution System (WDS) and water use for ease of determining the Non-Revenue Water (NRW). [ABSTRACT FROM AUTHOR]

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.;

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. HIGHLIGHTS Panel data analysis offers nuanced spatiotemporal insights departing from cross-sectional methods.; Holistic approach examines water supply, quality, and cost, unlike prior single-focus studies.; Innovative metrics introduced include performance score and water quality index.; Practical insights help identify cost-effective water treatment plants and key determinants.; Sustainability focus emphasizes continuous monitoring and community engagement.;

This paper aims to assess non-revenue water (NRW) in the urban water distribution system in Cameroon. The methodological approach used in this study was based on online searches using the databases such as Google Scholar, Web of Science, PubMed, and the International Water Association. These online searches have been completed through field observations and interviews with institutional and non-institutional stakeholders in the urban water sector. Results indicate that the total volume of NRW in the urban area of Cameroon was 100.26 million m3/year, which represents 52.5% of the total system input volume. About 2 million people could be supplied by cutting Cameroon's NRW to half the present level. Findings also suggest that the water utility (Camwater) practices passive leakage control, meaning that Camwater repairs only those leaks that are visible. Reducing NRW can be achieved through leakage detection and pipe replacement, pressure management, water metering, and a program to identify, remove, and replace illegal connections. HIGHLIGHTS This study shows that the annual volume of non-revenue water (NRW) is estimated at 274,679.2 m3/day, or 100.26 million m3/year, which represents about 52.5% of the annual system input volume.; About 4 million people (14% of the population) could be supplied with the present level of NRW.;

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]

Non-revenue water (NRW) in Luangprabang City, Laos, has been high and fluctuating. Therefore, we aimed to analyze the factors influencing the fluctuation of NRW in two district-metered areas (DMAs). The average NRWs for 16–17 months in DMA-1 and DMA-2 were 28.92 and 43.92%, respectively, whereas the coefficients of variation of the monthly NRWs were high at 49.7 and 11.7%, respectively. Among the factors causing the fluctuation of NRW, meter inaccuracies were less than 2%, although inaccessibility to customer meters was high at 46.4 and 38.7% in DMA-1 and DMA-2, respectively. However, the meter reading intervals had little influence on billed water consumption. Using the IWA Water Balance table, the apparent loss was estimated as 2.6%, whereas the real loss (24.9%) was the main component of NRW (27.5%) in DMA-2. The monthly and 3–7-month moving averages of NRW were inversely correlated with billed water consumption, indicating that both volumetric and percentage NRWs were strongly influenced by fluctuations in billed water consumption. Network simulation verified that high inaccessibility to customer meters, particularly during the COVID-19 lockdown, caused large fluctuations in billed water consumption and NRWs. Therefore, access to customer water meters should be improved to alleviate the fluctuation of NRW. HIGHLIGHTS High rates of meter malfunction and inaccessibility caused NRW fluctuation.; Apparent loss was only 9.4%, whereas real loss was 90.6% for non-revenue water.; Volumetric and percentage NRWs are inversely correlated with billed consumption.; Taking moving averages helps find relations between water consumption and NRW.; Meter reading errors can be estimated using DMA inflow data and EPANET simulation.;

Non-revenue water poses a significant challenge to sustainable water management in municipalities worldwide. This study investigates the factors contributing to NRW and assesses the effectiveness of existing management strategies in three municipalities in Mpumalanga, South Africa. Through a survey-based approach, perceptions of municipality workers were collected to gain insights into the drivers of NRW and the efficiency of currently employed NRW management strategies. The findings highlight real losses; broken pipes, pipe bursts, water leakages, and storage overflows are perceived as the most significant contributing factors of NRW across all three municipalities. These results align with previous studies, emphasizing the importance of addressing real losses to mitigate NRW. Additionally, the study reveals management factors and political interference as perceived contributors to increased NRW in the municipalities. In terms of management strategies, modern flow metering is employed in two of the municipalities to control active leakage, while the third municipality relies on active leakage control equipment. Pressure management practices, automatic pressure-reducing valves, and regular asset performance assessments were identified as common practices for managing and mitigating NRW, whereas the use of smart metering technologies, modern leakage detection techniques, zoning (district metered areas), and improved estimation techniques were proposed as mitigation strategies with the potential to further reduce NRW in the three municipalities. The study fills a research gap by providing insights into the specific factors contributing to NRW in the selected municipalities and evaluating the effectiveness of existing strategies. The results of the study can inform decision-makers and water utility managers in developing targeted interventions to reduce NRW and improve water management practices. It is further recommended that future studies explore the implementation and long-term effectiveness of some of the proposed mitigation strategies to effectively address NRW in order to ensure sustainable water supply, efficient resource utilization, and improved service delivery.

By 2050, over 40% of the global population could face severe water stress. The 2030 Agenda explicitly integrates water resources, supply, and sanitation, emphasizing sustainability for present and future generations. Non-revenue water (NRW) creates a barrier to sustainability through energy, water loss, and money not collected through water bills. However, NRW is well recognized by water service providers, and a comprehensive solution is lacking. Addressing NRW is vital to sustainable operations and achieving the Sustainable Development Goals (SDGs). This desk literature review investigates NRW's links with SDGs, highlighting global and local impacts, flameworking interconnections, and revealing economic, social, and environmental consequences. The study revealed that NRW not only aligns with various SDGs, particularly SDG 6 and SDG 13, but also has synergies with other goals related to energy and sustainable consumption. Reducing NRW can achieve more sustainable and resilient water systems, and contribute to the broader SDG. The cost of NRW extends beyond the financial implications for water utilities. It also encompasses the economic impacts on industries and businesses, which impacts exceeded water productivity, increased operational costs, and economic development constraints. HIGHLIGHT Explores new methods of planning and management of NRW by indicators.;

Water infrastructure management relies on information, communication strategies, and affordable technologies. This paper used demand analysis and modeling to guide strategic decision-making in sustainable water management for the urban cluster in Tlemcen, Algeria. To achieve this, the water supply and demand of the study area were assessed over the past three decades. The Water Evaluation and Planning (WEAP) system was employed considering different future scenarios to help decision-makers consider the best choices for sustainable urban water resources management. The results showed that the average water production and distribution efficiency was only 46% due to the high network loss. Therefore, urgent action should be considered to increase the efficiency of the distribution network. Moreover, the outcome showed severe unmet demand in 2050, which can be managed by improving the water networks, increasing conventional water production, and reducing personal water consumption. In cooperation with key stakeholders, new scenarios can be analyzed to develop efficient water management policies and to implement sustainable water allocation approaches. [ABSTRACT FROM AUTHOR]

In order to optimally manage the pressure and reduce the non-revenue water as much as possible, taking into account the costs of each activity, it is necessary to examine the priority of each solution by scientific methods and considering the costs, efficiency and duration of implementation. Therefore, in order to avoid cost wastage and efficient use of financial resources, it is necessary to use a comprehensive and systematic approach to identify different strategies that can be used to manage urban water pressure, the benefits and Compare their disadvantages. In the statistical population of this research, the knowledge and experience of 35 experts in the water and wastewater industry were used. Also in order to prioritize the proposed operations with the aim of reducing non-revenue water based on three criteria: the impact of the project, the duration of the project and the cost of the project, the integrated TOPSIS-VIKOR method has been used. Findings indicate that in the first priority, the installation of online data loggers pressure gauges, the second priority is the continuous updating of water maps and GIS network mapping, and in the third priority the completion of its information layers including pipe life, material and diameter, were located.

In the new world view, water is considered an economic-social commodity and a basic human need. This work aims to investigate the relationship between corrosion and changes in the minimum night flow (MNF) rate in water systems. Changes in MNF as a dependent variable are affected by changes in independent variables such as total unreported water loss, allowed night consumption, and network field leakage. First of all, the share of water loss due to network corrosion in total unreported water loss was investigated through a mathematical model and regression analysis according to Geography Information System (GIS). As a result, the p-value for pressure was .564. The Power function had a suitable correlation on the scatter diagram and best-fit curve which was used for Inflow to the water distribution network based on the regression model. The error of the consumers' meter and the correction of these errors were discussed in the apparent water loss section. The apparent water loss value was equal to 1.12% of produced water. This amount of apparent water loss showed the share of the actual water loss due to network corrosion from the total unreported water loss in the facilities. HIGHLIGHTS Improvement of networked sensors.; Connection between GIS, RS, and IoT.; Relationship class definition for the water system.; Access to leakage locations by GIS, RS, and IoT.; Conceptual model for MNF and corrosion control.;

One of the most important accidents for water transmission lines occur by air entrance due to water hammer into the water pipeline at sub-atmospheric transient pressure. The air can be sucked into the water system causing repeated pipe breaks in sub-atmospheric transient pressure. This work aimed to improve the advanced techniques including remote sensing (RS), and the internet of things (IoT) to control the repeated pipe breaks. According to the geospatial information systems (GIS), the relationship classes between the spatial and non-spatial data were defined for the scaled model. By GIS the location of pipe breaks and sucking air into water pipeline was recognized during fluid instabilities. The location of pipe breaks was defined by the numerical modelling based on GIS. According to numerical analysis, the Courant number was equal to 0.977. In the field test, the surge velocity was 1084 m/s. The pressure wave was detected in 0.005 s by RS facilities equipped with water hammer sensors, advanced modems, and data loggers referring to the IoT technique. The result of this work led to a reduction of the non-revenue water (NRW) and the saving of drinking water. HIGHLIGHTS Connection between GIS, RS, and IoT for record the water pressure wave (in this work 0.005 s).; Conceptual modeling definition for prediction of the pressure wave variation due to water hammer.; Improvement of RS facilities installation equipped with data loggers, IoT and GEO-database.; Relationship class definition for water system elements for leakage points.; Make water and energy savings.;

Apparent losses and real losses are two main components of water losses in water supply systems (WSSs). Apparent losses are caused by water meter inaccuracies, illegal consumption, and data handling errors whereas real losses are associated with leakage, pipe bursts and overflow from storage tanks. In well managed WSSs, apparent losses mainly result from inaccuracies of water meters. Performance of water meters is affected from many factors such as meter type, class, size and age, installation, and water consumption profile. In this study, new and used multi-jet type water meters, which is one of the most widely installed water meter type, were tested under different flow rates in a laboratory setup for performance evaluation. Starting flow rates and metering errors of new and used multi-jet water meters under varying flow rates were tested. Average starting flow rate for the new multi-jet (MJ-N) water meters is determined as 7.02 l/h whereas the multi-jet water meters with an age of more than 9 years (MJ-3) old have the highest starting flow rate with an average value of 40.18 l/h. Meter degradation for average starting flow rates shows an almost linear trend. All tested water meters tend to make more measurement errors at lower flow rates. As measurement errors for ageing meters (MJ-2 and MJ-3) are similar at medium and high flow rates, ageing of meters cannot be described by linear degradation. This study showed that ageing and water consumption profiles have a great impact on water meter performance. An evaluation on ageing effects on the accuracy of water meters is provided in this study. [ABSTRACT FROM AUTHOR]

In this study, it has been revealed that physical water losses in drinking water networks are one of the important issues in the protection of water resources. The demand for drinking water is increasing day by day with the increase in population. On the other hand, the amount of potable water is decreasing and the effective use of water in drinking water networks becomes important. The water that is given to the water network but does not reach the users is known as lost leakage. Lost and leaks are called physical and visible losses. In order to determine the water loss and leakage level in the research, the amount of water supplied to the system for 2020, the number of pipe failures, the amount of water consumption according to the usage areas, and the minimum night flow information were obtained from the municipality. In order to determine the water loss and leakage level in the Merzifon sample, the infrastructure leakage index was determined by creating a water balance. In the sample of Merzifon, it was determined that the amount of physical water loss and leakage for 2020 was 44.12%. The infrastructure leak index (ILI) was determined as 13.6. In order to protect the water supply, pressure management in the drinking water network, network renewal, active leakage control, improvement of repair speed and quality should be done. [ABSTRACT FROM AUTHOR]

One of the main challenges undermining water supply in African cities is the rapid decay of networked infrastructures. Urban water managers, policymakers and researchers, however, have paid little attention to repair and maintenance or to their importance for the operation and renewal of urban water utilities. Using a sociotechnical framework, this paper investigates the maintenance and repair practices of utility officials from two water companies, one in Accra and one in Dar es Salaam. More specifically, through the interplay of four variables, we develop a novel analytical framework inspired by science and technology studies to explain and compare the contingent, place-based maintenance and repair practices that shape urban water supply. These four variables are materialities, discourses, institutional arrangements, and the knowledge of local experts. The two aims of this paper are to explain how the 'everyday' repair and maintenance practices of utility officials shape water supply, and to draw lessons for improving water supply in both cities. Our findings show that repair and maintenance practices are strongly shaped by place-based materialities and contextual knowledge in water supply, but at the same time are contingent on wider national and international relations as reflected in discourses, policies, and the supply of technical and material spare parts.

Because of population growth, rapid urbanization, and climate change, many water supply utilities globally struggle to provide water that is safe to drink. A particular problem is the aging of the water supply facilities, which is exacerbated by their inefficient operation and maintenance (O&M). For this reason, many water utilities have recently been actively adopting intelligent and integrated water supply O&M solutions that utilize information and communication technology, the Internet of Things, big data, and artificial intelligence to solve water supply system problems. In this study, smart water solutions (GSWaterS) were implemented to enhance the efficiency of the water supply system in the city of Aracatuba, Brazil. They were used to monitor and analyze the operating conditions of the water supply system in real time, thus allowing for the effective management of water supply assets. GSWaterS also supports the design and optimization of district metered areas, the reduction and management of water losses, real-time water network analysis, and big data analysis using artificial intelligence. Economic analysis revealed that GSWaterS produces various direct and indirect benefits for the water supply system. [ABSTRACT FROM AUTHOR]

Water leakages in urban water supply networks are a major cause of non-revenue water (NRW) and pose significant challenges for water management. To address this issue, the Municipal Enterprise for Water and Wastewater of Aigialeia (DEYA Aigialeias), the Institutionalized Research Laboratory of Smart Technologies, Renewable Energy Sources and Quality of UNIWA (STRESQ), and the Laboratory of Climatology and Atmospheric Environment (LACAE, NKUA) are collaborating on a project titled “Smart system for Leak Detection for water supply Network of Aigio”. By installing sensors and implementing a SCADA system with PLC controllers, critical parameters such as water supply, pressure, and quality will be monitored. This project aims to reduce water leakage, which currently accounts for approximately 48% of the town’s total water supply, ultimately saving around 600,000 m3 of water annually.

Background: This research paper studied the parameters affecting the non-revenue water in Egypt. The neural model was developed to forecast the NRW ratio before and after network rehabilitation using main parameters and statistical data for various measured district metered areas (DMAs) in Egypt. The non-revenue water (NRW) ratio is a parameter of significant concern for the water distribution system's performance evaluation. Therefore, NRW ratio parameter evaluation requires analysis of variables that influence the NRW ratio. Aim/objective: This study aims to offer findings that will lay the basis for sustainable water resources management in Egypt.Consequently, a comprehensive evaluation of water distribution systems and parameters affecting NRW was conducted. Methodology: The predictive models were developed using the historical data of the water company for various measured district metered areas (DMAs) in Egypt. The automated meta-models were developed at steady-state and over a prolonged period using a series of principles, rules, and constraints. It was based on multi hidden units of feed-forward neural networks trained by the back-propagation algorithm. Thus, the iterative methods of weight adjustment and activation function of Levenberg-Marquardt was used. Two scenarios were assumed, one that has complete data of the DMA investigated while the other assumed total lack of knowledge. Therefore, four models were built to forecast multiple parameters affecting the percentage of non-revenue water. However, three models were combined to reach the final NRW ratio with no historical data. An optimal number of neurons was determined to be 10. Each model result was tested against numeral statistical indicators showing a different level of accuracy. Results: The model results showed high accuracy in NRW final estimation. The performance indicators (i.e., RMSE, MAE, and correlation) also showed that the machine-learning algorithm better identifies complex relationships between different parameters. The models developed in this research can be applied to other DMAs in Egypt. Overall, these findings indicate that the machine-learning model may be adequate for water companies seeking immediate, cost-effective and long-term improvement of their water distribution systems. Practical implication: Results can provide the basis for decision-makers to reduce costs after applying the rehabilitation process upon any new DMA created. This study presents a modelling approach that provides the best prediction of non-revenue water. It allows the use of a model that enables the accurate projection of NRW ratio and approximating NRW in Egypt and elsewhere in similar countries around the world. Thus, it will help decision-makers enhance the overall NRW ratio strategically across Egypt and elsewhere worldwide.

Efficiency optimization of urban water systems is a growing concern for water utilities worldwide. This case study aimed at evaluating the impact of using cloud-based tools on the reduction of both real (real-time network monitoring) and apparent water losses (integrated customer meters management) in two water utilities. The incorporation of smart water solutions with a methodology for the management and operation of the systems allowed us to diagnose, prioritize areas and define actions to improve efficiency. Using a real-time monitoring tool allowed us to categorize bursts and to evaluate their impact on water loss volumes and to identify operational inefficiencies regarding detection and repair times, particularly in small and medium bursts. Additionally, the implementation of an integrated customer meters management tool allowed for an optimized meter management reducing apparent losses by estimating metering errors more accurately, enabling the water utilities to replace meters based on specific lifespan. Digitalization, through the implementation of optimized algorithms and early warning systems, allowed the analysis of data in a methodical and prompt manner resulting in non-revenue water reduction up to 8% in 3 years while improving the digital organization of data and its quality (reliability and accuracy), interdepartmental organization and communication, capacity building and utilities’ image among stakeholders. HIGHLIGHTS Two water utilities implemented web-based tools to promote the sustainable reduction of non-revenue water.; Implementing a real-time monitoring tool, utility A and B decreased 13 million m3/year in real losses.; Using an integrated customer meters management web-tool, both utilities decreased apparent losses by 3.1 million m3/year.; Non-revenue water reduced by 8% overall, resulting in savings of 5.8 million € in 3 years.;

The methods for water loss management should be selected based on the needs, economy, applicability and current condition. Therefore, it is very important to develop a model that considers all components, actors, analyzes and offers the most appropriate alternatives. The aim of this study is to carry out a detailed evaluations for effective, efficient, sus tainable and strategic water loss management, to present a new strategic model and to create a literature discussion that will set a reference for future studies. It is thought that the proposed model will provide significant advantages to studies such as making the current condition analysis in detail, determining the performance indicators that can be calculated, defining the goals, and determining the most appropriate methods. Thus, it will be possible to calculate more accurate indicators according to the data situation, to set realistic goals according to the current situation and to suggest the most appropriate methods. [ABSTRACT FROM AUTHOR]

One of the main challenges undermining water supply in African cities is the rapid decay of networked infrastructures. Urban water managers, policymakers and researchers, however, have paid little attention to repair and maintenance or to their importance for the operation and renewal of urban water utilities. Using a sociotechnical framework, this paper investigates the maintenance and repair practices of utility officials from two water companies, one in Accra and one in Dar es Salaam. More specifically, through the interplay of four variables, we develop a novel analytical framework inspired by science and technology studies to explain and compare the contingent, place-based maintenance and repair practices that shape urban water supply. These four variables are materialities, discourses, institutional arrangements, and the knowledge of local experts. The two aims of this paper are to explain how the 'everyday' repair and maintenance practices of utility officials shape water supply, and to draw lessons for improving water supply in both cities. Our findings show that repair and maintenance practices are strongly shaped by place-based materialities and contextual knowledge in water supply, but at the same time are contingent on wider national and international relations as reflected in discourses, policies, and the supply of technical and material spare parts. [ABSTRACT FROM AUTHOR]

This study examines how Samoa improved the capacity of Samoa Water Authority (SWA) by implementing integrated cooperation with water utilities in Okinawa Prefecture, and hardware and software development to reduce the high non-revenue water (NRW) ratio and improve water supply quality and inadequate water pressure. Standard operation procedures were formulated to enhance the capacity of SWA. The cooperation method adopted continuous on-the-job training with a bottom-up approach. Consequently, the NRW ratio was reduced from 68 per cent to 36 per cent and water supply with proper pressure was achieved in the targeted area. The quality of the tap water, in which many coliform bacteria were detected before the cooperation, achieved 100 per cent compliance with standards. The cooperation evidenced that improving water services can help users' understanding of tariff payments, although the water tariff increased for most consumers due to a shift from fixed to metered tariff. [ABSTRACT FROM AUTHOR]

The control of water loss in distribution systems has been highlighted in multiple discussions in the field of water and sanitation. However, there are few scientific studies on this topic that have focussed on loss control performance in developing countries. With the intention to expand the limited scientific framework investigating the management of water losses in economic scarcity scenarios, this paper provides an overview of which practices directed to water loss control are being conducted in a Brazilian region. Data were collected from 42 water utilities and show there is a direct relationship between the utilities' performances and the number of water loss practices adopted. The divergences in the number of practices applied by the water utilities may be influenced by technical–operational, planning and management factors. The paper brings greater robustness to the loss management debates in regions with economic scarcity, being able to support the action of utilities operating in similar scenarios. HIGHLIGHTS The mix of practices in water loss control is substantial for superior utilities performance.; A relationship between water utilities’ performances and number of water loss control practices applied is observed.; Factors that influence water loss control are discussed.; A greater robustness to debates of loss management in developing countries is provided.;

Water is one of the most essential needs in human daily life. Water losses or Non-Revenue Water (NRW) refers to the treated water that has been produced from water plant which did not reach to the customer. This waste of water has caused the company to suffer losses and hence, burdens the people with increasing water tariff. Moreover, it becomes one of the challenges for commercial water system management because the water company must fulfil the demand from the society which keep increasing day by day. In addition, the demand for water is increasing, as the population is growing. Despite having the rainfall throughout the year in Malaysia, many cities are experiencing water shortage and frequent water supply disruptions. Therefore, efficient management of water distribution is required to minimise the water losses and to make sure the sustainability of water reserve for a long period. This study focuses on identifying the significant factors that influence the Non-Revenue Water and modelling the data using Multiple Linear Regression Model. The sample size used in this study were 212 observations and the variables involved were Length of Connection, Number of Connection, Production Quantity, Consumption Quantity and Non-Revenue Water. It is found that the variables of Number of Connection, Consumption Quantity and Production Quantity were significant to Non-Revenue Water whereas the variable of Length of Connection was not significant. It is hoped that the result from this study can be used by the water authority company in improving the water distribution and thus reduce water losses and cost.

In water loss management, monitoring system behavior and analyzing system performance according to appropriate indicators is very important for improving operating conditions. However, appropriate calculation tools should be used to make these analyzes accurately, regularly, systematically and precisely. Therefore, in this study, the most appropriate indicators were determined based on the indicators proposed IWA and other organizations in literature in order to analyze and monitor the process performance in water loss management. A web-based "GGS basic performance analysis calculation tool" has been developed to systematically calculate these indicators and monitor performance. This tool basically includes volumetric and percentage indicators, service connection and per line length indicators, administrative and physical loss, economic and cost, failure and network rehabilitation indicators. The details of this tool were detailed, its advantages were discussed by analyzing of sample data set. It is believed that this analysis tool developed in this study will provide significant contributions to the analysis and monitoring of the performance of the Utilities in terms of water loss management and its components, and to evaluate the process performance for active leakage control activities

With a growing urban population and increasing climate uncertainty, it is necessary to quantitatively understand the flux of resources through cities, specifically energy and water resources. Many methods exist to analyze the urban energy–water nexus based on either physical characteristics of the system or using available data. While data‐driven approaches can be valuable, they are often challenging to duplicate on a large scale due to data availability, or they do not allow for drawing specific, detailed conclusions. Our work seeks to remedy these challenges by using multi‐resolution data and a mass balance approach to provide a reproducible and scalable method for analyzing water and embedded energy systems in cities with varying levels of infrastructure and technological advancements. Using a combination of utility‐scale and meter‐level data, we provide several quantitative performance gauges on a monthly and annual time scale. This process reveals notable seasonal variation in water demand, non‐revenue water, and embedded energy, providing a holistic understanding of water and its embedded resources. Our work further confronts the challenges of integrating disparate data sets into a uniform format to allow for accurate analysis. These particular data, coupled with a mass balance methodology, facilitate the examination of an urban area from top‐down and bottom‐up perspectives, yielding opportunities to quantify additional performance metrics beyond a single approach. [ABSTRACT FROM AUTHOR]

This study sought to determine daily water consumption in the three zones of Sumbawanga Urban district. The study applied the geographical information system (GIS) to map and quantify non-revenue water (NRW), and tested the use of geospatial database management strategy to reduce NRW. The study used water distribution networks of zone A (Majengo ward), zone B (Katandala and Mazwi wards), and zone C (Chanji and Kizwite wards) that are served by the Sumbawanga Urban Water Supply Authority (SUWASA). The study collected water flow and water loss data by recording and mapping the existing water networks using a GPS device. The methodology for determining the quantity of NRW abstracted from the International Water Association (IWA), and maps made through QGIS, were used to show the degree of water loss by zones. A geo-database that assists in maintenance, budgeting, planning and procurement of water assets to reduce NRW was developed using postgress and postGIS, and connected to QGIS for visualization. Experimental results and computations indicate that around 8787.6m3, 10718.3m3, 14637.1m3 of water are consumed monthly in zones A, B and C, respectively. Furthermore, the results show that averages of 15.15%, 40.2%, and 24.52% of water are lost as NRW in zones A, B, and C, respectively. The NRW in all the three zones were greater than the maximum NRW of 20% recommended by Energy and Water Utilities Regulatory Authority (EWURA), and key performance indicators suggested by the SUWASA. This study inform planners and decision-makers that management strategies should employ GIS to establish optimal routes for effective and quick response to bursts before losing a lot of water, instead of using traditional auditing systems that results into high NRW levels. [ABSTRACT FROM AUTHOR]

Effective strategies for optimal management of water distribution networks (WDNs) along with financial resources are clearly identifying design and performance parameters affecting the emergence of non-revenue water and reducing the impact of parameters. In this study, using references and experiences of experts in the field of WDN, the factors that are involved in the development of non-revenue water components were identified. Then, to collect the required information on the status of the parameters, officials’ and experts’ opinion were asked through questionnaires. Bayesian Networks (BNs) were used as a modeling tool so as to not only consider uncertainties associated to the lack of sufficient data and detailed information on non-revenue water components but also consider the probabilistic relationships between parameters. Finally, in order to analyze BN models results, a sensitivity index was proposed to prioritize parameters based on their impact. To investigate the usefulness of the proposed model, the area covered by District 4 of Tehran Water and Wastewater Company was selected as a case study. The results indicated that the probability that apparent losses, real losses and non-revenue water are high is 37.48 %, 35.04% and 32.2%, respectively.

Revenue water flow is defined as the amount of water for which the water rate has been collected, against tap water production, whereas non-revenue water (NRW) is defined as water that has been produced, but for which payment cannot be charged. In South Korea, there are big differences in NRW among the regions, and the NRW ratio in urban areas is higher than in rural regions. To reduce regional differences and effectively manage the water system, a management system to lower the NRW ratio is required. In particular, the NRW ratio can be reduced through an automatic leakage detection and sensor-error automatic checking system for feed water pipes and piping in household, and through leakage detection of water supply and drainage pipes that transport large volumes of water. Therefore, this study develops a system that can generate automatic alarms whenever abnormal usage is predicted via analysis of household water flow rate. Linear regression, ARIMA model, and additive regression model are compared to find the best method with high accuracy. The proposed method can support efficient water system management to lower the NRW ratio.

The aim of this study is to determine the priority areas in the meter replacement or rehabilitation by using an integrated methodology combining the AHP and ELECTRE I methods to reduce the non-revenue water. For this, a total of 7 criteria such as the Water Consumption Rate, Mean Meter Age, Faulty Water Meter Ratio, Region Population Rate, Customer Loyalty Percentage, Average Operating Pressure and Calibrated Age were considered. The AHP method was applied to calculate the weights of the criteria and then a model based on weights of criteria was developed using the ELECTRE I method. The model based on AHP and ELECTRE I methods was applied by taking into account the field data records for 7 criteria and the priority regions in water meter replacement were determined. This study will make significant contributions in the scope of minimizing the losses caused by the meters, reducing the costs in meter management and making the most benefit in meter replacement. [ABSTRACT FROM AUTHOR]

Jalur Baru Kedung Halang Branch is one of distribution pipeline in Perumda Air Minum Tirta Kahuripan which has 70,42% of Non-Revenue Water (NRW) value and 24,69% of physical water losses. Reducing physical water losses was an effort to reduce NRW value. The aim of this research was to determine the effect of pressure management on physical water losses. The methode of the analysis in this research was carry out by simulation using the epanet 2.2. Based on the results of the analysis, the pressure management using Pressure Reducing Valve (PRV) and setting the work periode of pumps based on peak hours and minimum hours could reduce physical water losses by 4,38%, thus 40.656 m³ of water can be saved in a year. [ABSTRACT FROM AUTHOR]