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The paper presents some of the most common operational problems in water pipe networks, studied in the water distribution system of Athens, the capital of Greece. The study, which took place from 1995 to 2000, concerning individual pipes of a network with a total length of 7,000 km, was based on the leakage and pipe break records kept by Athens Wat...
Citations
... Many studies have shown that a significant portion of leakages can be attributed to flaws in the connections between pipelines, which corresponds to more than 50% of the total water losses, even in cases when networks exhibit low link density [44,46,93,94]. ...
While only a minimal fraction of global water resources is accessible for drinking water production, their uneven distribution combined with the climate crisis impacts leads to challenges in water availability. Leakage in water distribution networks compounds these issues, resulting in significant economic losses and environmental risks. A coherent review of (a) the most widely applied water loss estimation techniques, (b) factors influencing them, and (c) strategies for their resilient reduction provides a comprehensive understanding of the current state of knowledge and practices in leakage management. This work aims towards covering the most important leakage estimation methodologies, while also unveiling the factors that critically affect them, both internally and externally. Finally, a thorough discussion is provided regarding the current state-of-the-art technics for leakage reduction at the municipal-wide level.
... The management of a water distribution system aims to satisfy water demands with minimum operational costs (Kanakoudis, 2004). Water supply networks to be reliable should have sufficient distribution capacity to meet the consumption requirements in terms of both quantity and pressure of the supplied water (Shinstine et al., 2002). ...
This paper examines the reduction of pump energy consumption at existing water distribution networks through a selective pipes' replacement with new pipes of greater diameter. The selection of diameter is conducted via a Genetic Algorithm which searches for pipes and their diameters that will have the biggest impact in the increase of pressures, on condition that the pressure of each junction does not exceed a maximum value. By testing different budgets each time, we obtain different changes in diameters and consequently increase pressures. Then the pressures are reduced by decreasing the heads of the pumps in order to reach the initial pressure values. Thus, as the pump's head decreases, we have a different operational cost of the network, which translates into long-term energy and economic benefit. Tests are conducted in Python through the package Water Network for Resilience (WNTR), which can run EPANET models. The method proposed is applied in Evaggelistria in Thessaloniki (Greece) resulting in lower pumps' heads.
... Earlier studies have indicated that pipe age should not be considered the only priority criterion (USEPA 2002), as pipe material, location, in terms of depth and soil properties, and installation practices are more important factors for predicting and preventing pipe bursts (O'Day 1987;Wengström 1993). This is supported by a study conducted in Athens, Greece, during 1995Greece, during -2000, concluding that 92% of the pipe bursts could be prevented if the pipe structural strength was sufficient and, therefore, the most efficient way to ensure service quality is to use corrosion-free pipe materials and collect and analyse data about the system's functioning to support data-based decision-making (Kanakoudis 2004). ...
... This selection is pivotal in safeguarding hydraulic installations against the adverse effects of pressure surges, as outlined by Fuertes-Miquel et al. (2019) [1]. Throughout the last decades, a considerable amount of attention has been focused on the examination of water hammer effects, primarily driven by incidents of pipe collapses, concentrating on monophasic conditions involving water [2,3]. ...
Starting up water installations is typically a task that falls within the purview of water utility companies. These operations involve the presence of two separate fluids (water and air) that can be analyzed in terms of consideration two distinct behaviors (hydraulic and thermodynamic). During a filling process, trapped air pockets exhibit a trend of declining volume, generating pressure surges that are typically not addressed under current worldwide regulations. This research introduces an innovative mathematical approach based on physical equations to investigate filling operations in water installations involving trapped air, incorporating an unsteady friction model (using the Brunone friction coefficient), in combination with the rigid water column model. The validation of the proposed model is carried out in an experimental facility measuring 7.36 m in length. The proposed model is then applied to a case study involving a 460 m long pipeline with an internal pipe diameter of 150 mm, featuring an undulating profile composed of three branches, to demonstrate how the gravity term should be calculated in real-world water installations. The results showed that the proposed model, considering an unsteady friction model, is suitable for simulating the start up of water pipelines for the experimental facility analysis and the case study. The Swamee–Jain formula yielded the best results compared to other formulations for computing the friction factor.
... Water distribution systems (WDSs) play a crucial role in providing clean water and making it accessible to the population. However, the problem of leakage, along with other issues reported by many researchers (Mays 2000;Kanakoudis & Tolikas 2001;Kanakoudis 2004aKanakoudis , 2004b, in the distribution network is a persistent challenge faced by water supply companies worldwide. Leakages affect the system's efficiency, reduce the available water supply, and increase costs for repairs and maintenance. ...
Detecting leaks in Water Distribution Systems (WDS) is a challenging task for maintenance managers. One widely used method for leak detection is the Pressure Residual Vector method, which involves comparing pressure values with computed values. In this paper, a new approach using probability distribution function and entropy content is proposed to expand the applicability of the previous models. The study began by collecting real-time information on water consumption using automatic electromechanical water meters over a one-year period. Hourly parameters were calculated to determine the temporal pattern of water consumption per capita. Hypothetical leakage was then imposed on each pipe, and the average entropy of water head variations in the nodes was determined. A combinatorial search process was used to suggest a Pressure Gauge Network (PGN) in a WDS. The study found that after a certain number of pressure gauges, the increase in entropy content is insignificant. This quantity may be deemed as the number of pressure gauges required in the PGN. Furthermore, the study showed that the impact of leak parameters can be disregarded when designing a PGN for leak detection purposes. Overall, the study's findings can be used to design a PGN for leak detection in a WDS. Key words: entropy, leakage detection, pressure gauge network design, pressure residual vector method, water distribution system HIGHLIGHTS • Per-capita hourly consumption of water was obtained by field measurement. • The entropy concept is used to identify nodes that are most affected by failures in the distribution network. • These nodes are used as candidate nodes for installing pressure gauge sensors to detect leaks. • The effect of leakage parameters on the monitoring network is evaluated. • Information content reflected by pressure variation in nodes is reported.
... Water distribution systems (WDSs) play a crucial role in providing clean water and making it accessible to the population. However, the problem of leakage, along with other issues reported by many researchers (Mays 2000;Kanakoudis & Tolikas 2001;Kanakoudis 2004aKanakoudis , 2004b, in the distribution network is a persistent challenge faced by water supply companies worldwide. Leakages affect the system's efficiency, reduce the available water supply, and increase costs for repairs and maintenance. ...
Detecting leaks in Water Distribution Systems (WDS) is a challenging task for maintenance managers. One widely used method for leak detection is the Pressure Residual Vector method, which involves comparing pressure values with computed values. In this paper, a new approach using probability distribution function and entropy content is proposed to expand the applicability of the previous models. The study began by collecting real-time information on water consumption using automatic electromechanical water meters over a one-year period. Hourly parameters were calculated to determine the temporal pattern of water consumption per capita. Hypothetical leakage was then imposed on each pipe, and the average entropy of water head variations in the nodes was determined. A combinatorial search process was used to suggest a Pressure Gauge Network (PGN) in a WDS. The study found that after a certain number of pressure gauges, the increase in entropy content is insignificant. This quantity may be deemed as the number of pressure gauges required in the PGN. Furthermore, the study showed that the impact of leak parameters can be disregarded when designing a PGN for leak detection purposes. Overall, the study's findings can be used to design a PGN for leak detection in a WDS.
HIGHLIGHTS
Per-capita hourly consumption of water was obtained by field measurement.;
The entropy concept is used to identify nodes that are most affected by failures in the distribution network.;
These nodes are used as candidate nodes for installing pressure gauge sensors to detect leaks.;
The effect of leakage parameters on the monitoring network is evaluated.;
Information content reflected by pressure variation in nodes is reported.;
... Different from pipe cracking can be immediately detected and repaired, water leakage frequently escapes notice for a long time. 1 Water leakage frequently occurs by elevated pressures, corrosion, aging infrastructure, water quality degradation, and third-party damage. 2 Rates of water leakage are also affected by weather conditions. 2 It is estimated that 40-50% of drinking water is lost due to leakage in developing countries, 3 whereas less than 10% is lost in countries with well-maintained infrastructures such as Japan. 4 In Taiwan, the percentage of people served by tap water was 94.39%, but the rate of leakage was 12.71%, in 2019 (Taipei Water Department, 2020). ...
... Different from pipe cracking can be immediately detected and repaired, water leakage frequently escapes notice for a long time. 1 Water leakage frequently occurs by elevated pressures, corrosion, aging infrastructure, water quality degradation, and third-party damage. 2 Rates of water leakage are also affected by weather conditions. 2 It is estimated that 40-50% of drinking water is lost due to leakage in developing countries, 3 whereas less than 10% is lost in countries with well-maintained infrastructures such as Japan. 4 In Taiwan, the percentage of people served by tap water was 94.39%, but the rate of leakage was 12.71%, in 2019 (Taipei Water Department, 2020). ...
A method of in‐situ leakage diagnosis of a water supply network using fire hydrant water flow measurements and simulation by EPANET software was established. A network with 1032 m of water distribution pipes and 350 user‐side water meters in Taipei was separated into five zones. The lowest volume of daily water flow occurred between 1:00 a.m. and 6:00 a.m., with values ranging from 0.004 to 0.785 m³/min; these data can be regarded as a minimum value of water leakage in the network at midnight. The volume of water leakage was strongly correlated with observed pressure transients, enabling the measurement of the water leakage in the network, which ranged from 5.76 to 628 m³/d. The total water leakage simulated by EPANET was 1.48×103 m³/d in the network. Although this value deviated by 23% from the District Metered Area (DMA) results, both EPANET and DMA tools confirmed that zones 4 and 5 had severe water leakage problems. Simplifying valves and combining neighboring pipes of the same diameter during the EPANET simulation was efficiently tackle water leakage. EPANET allows for quick diagnosis of the water leakage areas, whereas the DMA tool allows for precise measurements of water volume and pressure. The costs of in‐situ diagnosis and EPANET simulation include instruments, labor, and time, and are estimated to be lower than those of the DMA tool. Furthermore, the methodology of this study can reduce the risks of underground working disasters.
... Nevertheless, mechanical loads are affected by the covering soil properties and the construction method [136]. Generally, adopting a suitable construction method and adequately selecting the bedding and backfilling material reduce the mechanical loads induced by the traffic loads [62]. ...
The deterioration of water pipes causes significant socio-economic and environmental burdens. Many predictors/factors are used to mitigate such problems by modelling the water pipe deterioration. However, these predictors have not been thoroughly investigated in the literature. This study adopts mixed systematic and scientometric analyses to review the predictors used in modelling water pipe deterioration. Within the study context, the predictors are categorised into pipe-related, soil and corrosion-induced, operational, and environmental. The results reveal that the pipe-related predictors have received the most attention in the reviewed studies, whereas further investigations are required to study long-term changes in the environmental-induced predictors. Accordingly, future research directions are recommended to fill these gaps (e.g., considering sustainability issues, and deploying real-time monitoring, and IoT facilities to enhance data availability. These directions greatly benefit practitioners and researchers from multidisciplinary backgrounds in research directions related to water pipes.
... Corrosive substances: The presence of corrosive substances in water, such as chlorine, or a high concentration of dissolved salts and minerals, degrade the material of a pipe, which can ultimately cause its failure (Rehan Sadiq et al., 2010). For a WDN located in Greece, Kanakoudis (2004) found that the presence of high levels of iron concentration turns the flowing water to red, which contributes significantly to the corrosion of the pipes and, eventually, their failure. ...
The need for sustainable water infrastructure systems continues to grow as clean water is essential for daily life.
Despite efforts to sustain water distribution networks (WDNs), they often experience frequent failures, leading to
several environmental, social, and economic consequences. Previous studies have investigated the causes of
water pipe failure in different contexts. However, a comprehensive and holistic understanding of these causes is
lacking in the literature. Therefore, this study contributes to the existing knowledge by presenting 1) a scientometric
analysis of the previous literature, 2) a systematic discussion of the causes, 3) an Analytical Hierarchy
Process model and fault tree logic to prioritize and map the causes, respectively, and 4) an overview of techniques
used in developing failure prediction models. The scientometric analysis reveals that little attention has
been paid generally to the operational causes of water pipe failure. The same trend was supported by the systematic
review, which divides a total of 33 causes into three main categories: pipe-related, environment-related,
and operation-related causes. This study gives insights to academics and practitioners working in this domain on
the contributions of various factors to the failure of water pipes, which would be useful in designing a sustainable
and resilient WDN.
... An efficient and effective operation and management of WDS requires that the gathered and stored data can be combined into a single platform to help the utility managers and operators to address their operational and infrastructural problems, namely, related to assets' ageing, non-revenue water, water stress and scarcity, and variability of hydrologic events from climate change, among others [8][9][10][11]. This process is typically called data integration. ...
This paper presents a set of computational tools specially developed for supporting the operation and management of water distribution systems towards digital transformation of water services. These tools were developed in the scope of two R&D projects carried out in Portugal, DECIdE and WISDom, during 2018–2022. The DECIdE project focused on the development of tools for importing cadastral and operational data, as well as on the three operational tools for supporting the performance assessment: the first allows the calculation of different key performance indicators, both at a global and sectorial level, which is an annual requirement of the water regulator, and the other two allow the calculation of the water and the energy balances and a set of complementary indices. The WISDom project aimed at the implementation of applications that directly address specific water utility needs, namely, the flow rate data processing, the optimal location of pressure sensors, the identification of critical areas in the distribution network for pipe burst location, and the prioritization of pipes for rehabilitation. Implemented tools are useful to support water utilities in the daily operation and management of their systems, being a step forward towards digital transformation of the water sector.
