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Sustainable water management has been a trending goal in the past decade. Non-revenue water (NRW) is one form of water loss that should be addressed to reach water sustainability. While rehabilitating water distribution networks (WDNs) is one way to decrease NRW, the process is often delayed owing to cost. Therefore, it is essential to provide decision-makers with cost-effective approaches to optimize WDN rehabilitation. This study aims to evaluate the cost-effectiveness of approaches for rehabilitating WDN from developing countries’ perspectives.

A systematic literature review was first conducted to identify different WDN rehabilitation methods and techniques to develop the questionnaire survey. This is followed by collecting questionnaire survey data in Malaysia and Egypt on the cost and effectiveness of the WDN rehabilitation methods and techniques. A total of 176 respondents were collected, 109 from Malaysia and 67 from Egypt. Then, the data were analyzed using mean score ranking with normalization technique and agreement analysis.

The results from the data analysis show that the cost-effective approaches are “programming,” “simulation,” “digital twin” and “supervisory control and data acquisition.” Additionally, the data from Malaysia suggest two additional cost-effective approaches: “zoning network” and “genetic algorithm.”

To the best of the authors’ knowledge, this paper presents one of the first studies that laterally compares the cost-effectiveness of existing and potential WDN rehabilitation approaches between different countries. There is yet a study that compared these WDN rehabilitation approaches. This comparison which is developed depending on the systematic review could be a reference for future studies or surveys which could be done on different countries in the future. The main findings of this paper can be a useful reference for decision-makers, especially those from middle-income countries, when looking into approaches for WDN rehabilitation. A better WDN rehabilitation supports NRW reduction, moving towards sustainable water management.

This study aims to develop a decision support tool to improve planning for the rehabilitation of water distribution networks (WDN) using the analytical hierarchy process (AHP) method and the urgency level score.

In this paper the AHP method was used to outclass the indicators having a strong influence on the deterioration of the pipes and the score of the level of urgency is calculated to establish the rehabilitation program (short, medium and long term). The proposed model was tested for the case of the city of Souk-Ahras in Algeria.

Based on the judgments of twenty-four experts, the relative weights of the three physical, operational and environmental criteria of the pipeline were calculated and found to be equal to 35.40%, 55.60% and 9.00%, respectively. The two indicators, number of failures and pressure, were found to have the highest overall weights. The results of this article can be used to improve decision-making in WDN rehabilitation planning in Algeria.

The main objective of water companies is to provide citizens with good quality drinking water in sufficient quantity. However, over time, WDN age, degrade and deteriorate. This degradation leads to a drop in the performance through the degradation of water quality and an increase in loss rates. WDN rehabilitation is one of the most widely adopted solutions to address these drawbacks.

Application of a hybrid method (AHP- Level of Emergency) for the planning of the rehabilitation of WDN in Algeria.

Sustainability involves ensuring that sufficient resources are available for current and future generations. Non-revenue water (NRW) creates a barrier to sustainability through energy and water loss. However, a comprehensive overview of NRW reduction strategies is lacking. This study reviews the existing literature to identify available strategies for reducing NRW and its components and discusses their merits.

A systematic literature review was conducted to identify and analyze different strategies for reducing NRW. The initial search identified 158 articles, with 41 of these deemed suitably relevant following further examination. Finally, 14 NRW reduction strategies were identified from the selected articles.

The identified NRW reduction strategies were grouped into strategies for reducing (1) apparent losses (AL), (2) real losses (RL) and (3) water losses, with the latter involving the combination of AL and RL. The strategies adopted most frequently are “prevent water leakage” and “control water pressure.” In addition, water distribution network (WDN) rehabilitation has additional benefits over other RL reduction strategies, including saving water and energy, increasing hydraulic performance and enhancing reliability. Finally, utilizing decision support systems is the only strategy capable of reducing multiple NRW categories.

This review provides insights into the overall NRW problem and the strategies best equipped to address it. Authorities can use these findings to develop case-specific NRW reduction action plans that save water and energy, while providing other economic benefits. In addition, NRW reduction can improve WDN reliability.

Water distribution networks (WDNs) must deliver water to its customers 24/7. Disruption of this important service after a strong seismic event impedes post-disaster activities and poses health and sanitation problems. Hence, WDNs must be able to quickly restore services after the occurrence of a major seismic event. This ability to return the water service can be a metric for resilience. The purpose of this paper is to quantify the resilience by developing a framework that translates various restoration strategies into an improved resilience measure for a multisource WDN.

This paper used a quantitative risk assessment method in developing the framework for the resilience quantification of WDN. Prim’s algorithm, Horn’s algorithm and maximum slope method are used for the restoration analysis conducted in this study.

This paper provides resilience indices of the WDN for each repair scenarios. Then, the resilience indices are used to determine the most efficient and optimized repair scenario to restore the hypothetically damaged WDN owing to Level 1 and Level 2 seismic events.

The developed framework of this study only focuses on the robustness, rapidity and resourcefulness properties of resilience.

This study aims to help the water district in the maintenance, repair and evaluation of WDN against seismic events. The results from the study can be used in preparing the disaster management plan of the local water district to repair possible pipelines. This study also serves as a starting point to more complex and comprehensive research about the resilience quantification of WDNs with the consideration of optimal restoration sequence in the future.

The developed framework in the resilience quantification of WDN is original, as it uses optimal restoration strategies to represent the rapidity property of resilience.

In recent years, centrality measures have been extensively used to analyze real-world complex networks. Water distribution networks (WDNs), as a good example of complex networks, exhibit properties not shared by other networks. This raises concerns about the effectiveness of applying the classical centrality measures to these networks. The purpose of this paper is to generate a new centrality measure in order to stick more closely to WDNs features.

This work refines the traditional betweenness centrality by adding a hydraulic-based weighting factor in order to improve its fit with the WDNs features. Rather than an exclusive focus on the network topology, as does the betweenness centrality, the new centrality measure reflects the importance of each node by taking into account its topological location, its demand value and the demand distribution of other nodes in the network.

Comparative analysis proves that the new centrality measure yields information that cannot be captured by closeness, betweenness and eigenvector centrality and is more accurate at ranking the importance of the nodes in WDNs.

The following practical implications emerge from the centrality analysis proposed in this work. First, the maintenance strategy driven by the new centrality analysis enables practitioners to prioritize the components in the network based on the priority ranking attributed to each node. This allows for least cost decisions to be made for implementing the preventive maintenance strategies. Second, the output of the centrality analysis proposed herein assists water utilities in identifying the effects of components failure on the network performance, which in turn can support the design and deployment of an effective risk management strategy.

The new centrality measure, proposed herein, is distinct from the conventional centrality measures. In contrast to the classical centrality metrics in which the importance of components is assessed based on a pure topological viewpoint, the proposed centrality measure integrates both topological and hydraulic attributes of WDNs and therefore is more accurate at ranking the importance of the nodes.

The increased complexity of water distribution networks (WDNs) emphasizes the importance of studying the relationship between topology and vulnerability of these networks. However, the few existing studies on this subject measure the vulnerability at a specific location and ignore to quantify the vulnerability as a whole. The purpose of this paper is to fill this gap by extending the topological vulnerability analysis further to the global level.

This paper introduces a two-step procedure. In the first step, this work evaluates the degree of influence of a node by employing graph theory quantities. In the second step, information entropy is used as a tool to quantify the global vulnerability of WDNs.

The vulnerability analysis results showed that a network with uniformly distributed centrality values exhibits a lower drop in performance in the case of partial failure of its components and therefore is less vulnerable. In other words, the failure of a highly central node leads to a significant loss of performance in the network.

The vulnerability analysis method, developed in this work, provides a decision support tool to implement a cost-effective maintenance strategy, which relies on identifying and prioritizing the vulnerabilities, thereby reducing expenditures on maintenance activities.

By situating the research in the entropy theory context, for the first time, this paper demonstrates how heterogeneity and homogeneity of centrality values measured by the information entropy can be interpreted in terms of the network vulnerability.