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Resilient and Robust Water Distribution Systems: State-of-the-Art and Research Challenges

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A special issue of Water (ISSN 2073-4441). This special issue belongs to the section "Urban Water Management".

Deadline for manuscript submissions: closed (10 October 2019) | Viewed by 50653

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Prof. Dr. Joong Hoon Kim

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Guest Editor

School of Civil, Environmental and Architectural Engineering, Korea University, Anam-ro 145, Seongbuk-gu, Seoul 02841, Korea
Interests: machine learning; optimization algorithms; hydroinformatics; water distribution systems; urban drainage systems; smart water grids
Special Issues, Collections and Topics in MDPI journals

Prof. Donghwi Jung

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Guest Editor

Department of Civil Engineering, Keimyung University, Daegu 42601, Korea
Interests: WDS resilience and robustness; data-driven anomaly detection; metaheuristic optimization algorithm
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues

During the last decade, the water distribution system (WDS) design, operation, and management paradigm has been shifted from probability-based reliability to a “resilience” scheme. WDS resilience is the system’s ability to gracefully degrade and promptly respond and recover from catastrophic failure events (e.g., earthquake, intentional contamination, system-wide cyber-attack). Therefore, WDS resilience generally focuses on the system’s multiperiod performances under pre- and post-failure conditions, rather than focusing only on the failure consequence.

This Special Issue is intended to include papers addressing WDS resilience, especially those which introduce novel resilience-based design, operation, and management methodologies. While system resilience consists of the so-called 4Rs (robustness, redundancy, rapidity, and resourcefulness), novel design and operational methodologies should be developed for successfully guaranteeing systems’ pre- and post-failure performances.

The first two of the resilience components are believed to be improved through physical measures. For example, WDS design limiting the variation of stochastic pressures (persistence of pressure's behaviour) results in a robust system. Having multiple alternative paths for water supply helps improve system redundancy. On the other hand, the last two components, rapidity and resourcefulness, can be enhanced by non-physical measures such as operation and management. High system rapidity decreases failure duration and thus total system impact of the failure. Prompt response can be achieved with, for example, effective and efficient on-line anomaly detection, location models, and well-trained repair teams. The distribution and operation scheduling of available resources (e.g., water and human resources) for emergency conditions should be optimized for high system resourcefulness.

While some of the aforementioned resilience aspects are now being widely studied, there are research gaps that have not yet been tackled. Among others, few efforts have been devoted to investigating the interdependence between the four subcomponents of WDS resilience. In addition, the role of smart metering should be questioned and identified in terms of WDS resilience improvement. We also welcome papers to fill these gaps.

Finally, high-performance optimization and machine learning algorithms are essential to solve the aforementioned WDS resilience problems based on various real-world failure scenarios and conditions. We expect papers on the state-of-the-art review of WDS resilience metrics and those that address emerging WDS resilience issues and problems.

We hope this Special Issue can (1) serve as a reference point from which readers review progress, recent trends, and emerging issues; and (2) shed light on the right future directions of WDS resilience studies.

Prof. Joong Hoon Kim
Prof. Donghwi Jung
Guest Editors

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Keywords

Resilience-based WDS optimal design, operation, and management models
Interdependence between robustness, redundancy, rapidity, and resourcefulness (4Rs of resilience)
Smart metering for WDS rapidity and real-time operation and management
High-performance optimization and machine learning algorithms
WDS response and recovery under catastrophic failure events
Anomaly detection, classification, and location (e.g., pipe burst and leakage, cyber-attack, intentional contamination)
Water distribution network topology and resilience
State-of-the-art review of WDS resilience metrics
Defining emerging WDS resilience issues and problems

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Published Papers (12 papers)

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Editorial

Jump to: Research, Other

7 pages, 188 KiB

Open AccessEditorial

Emerging Issues and Methodologies for Resilient and Robust Water Distribution Systems

by Donghwi Jung and Joong Hoon Kim

Water 2020, 12(3), 769; https://doi.org/10.3390/w12030769 - 11 Mar 2020

Cited by 1 | Viewed by 2510

Abstract

This editorial summarizes the 11 papers published in the Special Issue entitled “Resilient and Robust Water Distribution Systems: State-of-the-Art and Research Challenges” which were classified into five themes related to water distribution systems (WDSs): (1) state-of-the-art review on WDS resilience and robustness (ROB), (2) WDS performance quantification and recovery under earthquakes, (3) criticality analysis and visualization, (4) novel design methodologies, and (5) hydraulic parameter monitoring for WDS rapidity improvement. Following the provision of the number of views and citations of each paper in a brief manner, a paper in category (1) that reviewed recent studies on WDS robustness is summarized. Category (2) covers three papers on improving the WDS capacity to fulfil customers’ demands in the case of an earthquake, a representative catastrophic failure event, while category (3) includes papers on visualization methods to represent the system’s criticality. The studies included in themes (4) and (5) proposed novel design methods and monitoring approaches for improving WDS resilience, respectively. Contributions from each study are described in the context of WDS resilience. We hope that this Special Issue can (1) serve as a reference point from which readers review progress, recent trends, and emerging issues, and (2) shed light on the appropriate future directions of WDS resilience studies. Full article

(This article belongs to the Special Issue Resilient and Robust Water Distribution Systems: State-of-the-Art and Research Challenges)

Research

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19 pages, 4527 KiB

Open AccessArticle

Reliability Assessment Model of Water Distribution Networks against Fire Following Earthquake (FFE)

by Yuanzhe Li, Jinliang Gao, Huaiyu Zhang, Liqun Deng and Ping Xin

Water 2019, 11(12), 2536; https://doi.org/10.3390/w11122536 - 30 Nov 2019

Cited by 11 | Viewed by 3598

Abstract

Fire following earthquake (FFE) is a common secondary disaster that can inflict great damage to humans. A large number of seismic resilience evaluation methods have been proposed, but few of them consider the influence of FFE. In this study, a multi-scenario simulation based model was developed to evaluate the post-disaster performance of water distribution networks (WDNs) in supplying both firefighting flow and original demand under the effect of seismic damage and FFEs. Hypothetical earthquakes were generated and the spatial–temporal distribution of FFEs was simulated by the Poisson distribution model and the Weibull distribution model. The post-disaster performance was evaluated by two types of seismic reliability metrics. The developed model was applied to a WDN currently operating in China with eight pre-determined earthquake scenarios. The results showed that the firefighting flow was concentrated in the first few hours after the earthquake. Thus, the serviceability of both original demand and firefighting flow was influenced significantly within the first few hours, while little impact was observed after the concentrated firefighting flow was delivered. The proposed model quantified the WDN’s performance under specific seismic damage and potential FFEs, and can be used for the planning, design, and maintenance of WDNs. Full article

(This article belongs to the Special Issue Resilient and Robust Water Distribution Systems: State-of-the-Art and Research Challenges)

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13 pages, 2812 KiB

Open AccessArticle

Development of Failure Cause–Impact–Duration (CID) Plots for Water Supply and Distribution System Management

by Seungyub Lee, Sueyeun Oak, Donghwi Jung and Hwandon Jun

Water 2019, 11(8), 1719; https://doi.org/10.3390/w11081719 - 18 Aug 2019

Cited by 7 | Viewed by 4282

Abstract

Understanding the impact and duration (consequences) of different component failures (cause) in a water supply and distribution system (WSDS) is a critical task for water utilities to develop effective preparation and response plans. During the last three decades, few efforts have been devoted to developing a visualization tool to display the relationship between the failure cause and its consequences. This study proposes two visualization methods to effectively show the relationship between the two failure entities: A failure cause–impact–duration (CID) plot, and a bubble plot. The former is drawn for an effective snapshot on the range (extent) of failure duration and the impact of different failures, whereas the latter provides failure frequency information. A simple and practical failure classification system is also introduced for producing the two proposed plots effectively. To verify the visualization schemes, we collected records of 331 WSDS component failures that occurred in South Korea between 1980 and 2018. Results showed that (1) the proposed CID plot can serve as a useful tool for identifying most minor and major WSDS failures, and (2) the proposed bubble plot is useful for determining significant component failures with respect to their failure consequences and occurrence likelihoods. Full article

(This article belongs to the Special Issue Resilient and Robust Water Distribution Systems: State-of-the-Art and Research Challenges)

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23 pages, 4599 KiB

Open AccessArticle

Ranking Approach to Scheduling Repairs of a Water Distribution System for the Post-Disaster Response and Restoration Service

by Alicja Bałut, Rafał Brodziak, Jędrzej Bylka and Przemysław Zakrzewski

Water 2019, 11(8), 1591; https://doi.org/10.3390/w11081591 - 31 Jul 2019

Cited by 12 | Viewed by 3977

Abstract

On the maintenance task list of each water distribution system (WDS) operator, determination of the order of undertaken repairs seems quite a typical task. Characteristics of damages, their localization, and other factors that influence repair sequencing have a sound impact on the execution of such tasks. In the case of the most complex cases where numerous failures of different types occur at the very same time (i.e., due to earthquakes), there is a long list of selection criteria that have to be analyzed to deliver an objectively logical schedule for repair teams. In this article, authors attempt to find out if it is possible to define pipe rankings in having obtained the best factors for defined objective functions (criteria), making it feasible to deliver judicious repair sequencing. For the purposes of this paper, a survey has been carried out. Its conclusions made it possible to propose a method to create rankings of pipes and evaluate them using a selected multicriteria decision method: preference ranking organization method for enrichment evaluation (PROMETHEE). The work was carried out for five different disaster scenarios that had been supplied by ‘The Battle of Post-Disaster Response and Restoration’ organization committee. Obtained results might be further used to finetune this sequencing method of undertaken repairs, while conclusions could be useful to model similar events in WDS when required. This article is an extended paper based on the conference preprint presented at the 1st International Water Distribution Systems Analysis (WDSA)/International Computing & Control for the Water Industry (CCWI) Joint Conference in July 23–25, 2018 in Kingston, Ontario, Canada. Full article

(This article belongs to the Special Issue Resilient and Robust Water Distribution Systems: State-of-the-Art and Research Challenges)

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14 pages, 2419 KiB

Open AccessArticle

A Framework for Improving Reliability of Water Distribution Systems Based on a Segment-Based Minimum Cut-Set Approach

by Seokhyeon Kim, Hwan Don Jun, Do Guen Yoo and Joong Hoon Kim

Water 2019, 11(7), 1524; https://doi.org/10.3390/w11071524 - 23 Jul 2019

Cited by 9 | Viewed by 6450

Abstract

A framework is presented to effectively improve the water distribution system (WDS) reliability. The proposed framework first classifies pipes in a WDS into three reinforcement types through topological analyses and hydraulic simulations over the WDS; type 1: no reinforcement, type 2: increasing pipe durability, and type 3: installing valve(s) at both ends. Then two rules, rules 1 and 2, are implemented, in which rule 1 first reinforces the pipe with the lowest reliability but rule 2 preferentially reduces damage size by pipe failures represented as the expected number of customers out of service (EN). The proposed method was applied to Cherry Hill network, and considerably improved the WDS reliability from 0.137 to 0.483. Both approaches showed notable differences in changes of the EN at each step of reinforcement, where rule 2 showed a better capability to reduce the EN and detect vulnerable areas in the WDS than rule 1. In addition, a practical approach, maximizing valve installations and minimizing pipe replacements according to the reinforcement types in the system, provided an improved WDS reliability (0.423) close to that of the rule-based approach (0.483) using only 21% of the construction cost by the rule-based approach. The proposed framework can be guidelines for improving the WDS reliability under restricted budget and site conditions. Full article

(This article belongs to the Special Issue Resilient and Robust Water Distribution Systems: State-of-the-Art and Research Challenges)

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13 pages, 2271 KiB

Open AccessArticle

Criticality Analysis of a Water Distribution System Considering Both Economic Consequences and Hydraulic Loss Using Modern Portfolio Theory

by Seungyub Lee, Sangmin Shin, David R. Judi, Timothy McPherson and Steven J. Burian

Water 2019, 11(6), 1222; https://doi.org/10.3390/w11061222 - 12 Jun 2019

Cited by 13 | Viewed by 5952

Abstract

This study introduces an approach using Modern Portfolio Theory (MPT) to consider hydraulic resilience and economic consequence resilience of a water distribution system (WDS) to identify critical assets. ECLIPS (Economic Consequence Linked to Interruption in Providing Service), a way to represent loss of water provision as economic loss, is used to measure economic consequence following a reduction of WDS functionality. The approach is demonstrated using a hypothetical WDS and tested for pipe breakage and replacement scenarios using EPANET hydraulic simulations. First, the correlation between hydraulic resilience and economic consequence resilience was investigated to assess differences between two resilience measures for identifying pipe’s criticality for replacement. The results confirmed the two resilience measures exhibited differing responses (covariance = 0.2), suggesting that use of both would provide complementary insight. Results of the MPT analysis identified the benefits of balancing hydraulic and economic consequence resilience measures to yield lower risk. This study provides a practical approach to incorporate economic consequence into planning, design, and research applications identifying critical WDS assets. Full article

(This article belongs to the Special Issue Resilient and Robust Water Distribution Systems: State-of-the-Art and Research Challenges)

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12 pages, 323 KiB

Open AccessArticle

Robustness and Water Distribution System: State-of-the-Art Review

by Donghwi Jung, Seungyub Lee and Joong Hoon Kim

Water 2019, 11(5), 974; https://doi.org/10.3390/w11050974 - 9 May 2019

Cited by 15 | Viewed by 4080

Abstract

The resilience of a water distribution system (WDS) is defined as its ability to prepare, respond to, and recover from a catastrophic failure event such as an earthquake or intentional contamination. Robustness (ROB), one of the components of resilience, is the ability to maintain functionality to meet customer demands. Recently, the traditional probability-based system performance perspective has begun to shift toward the ROB and system performance variation point of view. This paper provides a state-of-the-art review of WDS ROB-based approaches proposed in three research categories: Design, operation, and management. While few pioneering works have been published in the latter two areas, an ROB indicator was proposed and thoroughly investigated for WDS design. Then, some future works are recommended in each of the three domains to promote developments in WDS ROB. Finally, a brief summary of this paper is presented, from which the final conclusions of the state-of-the-art review and recommendations are drawn. The new paradigm of WDS ROB-based design, operation, and management is in its infant stage and should be carved out in future studies. Full article

(This article belongs to the Special Issue Resilient and Robust Water Distribution Systems: State-of-the-Art and Research Challenges)

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18 pages, 2313 KiB

Open AccessArticle

A Comparative Study on a Hydraulic and Water-Quality Analysis Method for Determining Rechlorination Injection Points for a Water-Supply Network

by Sang Myoung Lee, Ho Min Lee, Do Guen Yoo and Joong Hoon Kim

Water 2019, 11(4), 697; https://doi.org/10.3390/w11040697 - 4 Apr 2019

Cited by 5 | Viewed by 4445

Abstract

Water supply facilities are vulnerable to extreme weather events, such as droughts and floods. To establish a sustainable solution that resists accidents and disasters, a distributed system is required. To supply high-quality tap water using the existing water-supply network, rechlorination facilities must be installed to secure residual chlorine at the pipe end. In this study, a process is developed to determine the injection points and dosages of rechlorination using the latest pressure-driven analysis. The method was compared to the results of demand driven analysis methods. The proposed model was applied to P City in Korea to draw results. A detailed evaluation was performed to study how water pressure head and demand-based hydraulic and water quality analysis results impact the injection points and dosages of rechlorination. Thus, the existing demand-based model shows significant spatial deviations in the pressure head in the presence of water pressure drops, which subsequently lead to over-estimation of chlorine injection dosages for maintaining the concentration of residual chlorine. However, the proposed model involves a numerically validated theory and draws more reasonable results for hydraulic, water quality, and rechlorination dosages. The proposed model can be used as a decision-making tool based on hydraulic analysis for the supply of water of a stable quality. Full article

(This article belongs to the Special Issue Resilient and Robust Water Distribution Systems: State-of-the-Art and Research Challenges)

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13 pages, 2405 KiB

Open AccessArticle

The Impacts of Spatially Variable Demand Patterns on Water Distribution System Design and Operation

by Kegong Diao, Robert Sitzenfrei and Wolfgang Rauch

Water 2019, 11(3), 567; https://doi.org/10.3390/w11030567 - 19 Mar 2019

Cited by 9 | Viewed by 3965

Abstract

Resilient water distribution systems (WDSs) need to minimize the level of service failure in terms of magnitude and duration over its design life when subject to exceptional conditions. This requires WDS design to consider scenarios as close as possible to real conditions of the WDS to avoid any unexpected level of service failure in future operation (e.g., insufficient pressure, much higher operational cost, water quality issues, etc.). Thus, this research aims at exploring the impacts of design flow scenarios (i.e., spatial-variant demand patterns) on water distribution system design and operation. WDSs are traditionally designed by using a uniform demand pattern for the whole system. Nevertheless, in reality, the patterns are highly related to the number of consumers, service areas, and the duration of peak flows. Thus, water distribution systems are comprised of distribution blocks (communities) organized in a hierarchical structure. As each community may be significantly different from the others in scale and water use, the WDSs have spatially variable demand patterns. Hence, there might be considerable variability of real flow patterns for different parts of the system. Consequently, the system operation might not reach the expected performance determined during the design stage, since all corresponding facilities are commonly tailor-made to serve the design flow scenario instead of the real situation. To quantify the impacts, WDSs’ performances under both uniform and spatial distributed patterns are compared based on case studies. The corresponding impacts on system performances are then quantified based on three major metrics; i.e., capital cost, energy cost, and water quality. This study exemplifies that designing a WDS using spatial distributed demand patterns might result in decreased life-cycle cost (i.e., lower capital cost and nearly the same pump operating cost) and longer water ages. The outcomes of this study provide valuable information regarding design and operation of water supply infrastructures; e.g., assisting the optimal design. Full article

(This article belongs to the Special Issue Resilient and Robust Water Distribution Systems: State-of-the-Art and Research Challenges)

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17 pages, 2638 KiB

Open AccessArticle

Comparative Study of Hydraulic Simulation Techniques for Water Supply Networks under Earthquake Hazard

by Do Guen Yoo, Joo Ha Lee and Bo Yeon Lee

Water 2019, 11(2), 333; https://doi.org/10.3390/w11020333 - 15 Feb 2019

Cited by 9 | Viewed by 3979

Abstract

Water supply facilities such as waterworks systems are facilities that supply residential and industrial water essential for humans to live and it is essential for these facilities to be prepared for earthquake hazards. In the present study, new hydraulic analysis procedures that can complement problems in existing model were proposed for performance quantification under seismic hazards. Detailed procedures for estimating the serviceability of water supply networks using pressure dependent demand (PDD) and pressure dependent leakage (PDL) techniques were proposed. The developed methodologies can simulate many pipe leakage and breakage situations more realistically. The methodologies were applied to representative pipe networks to investigate the models and new performance quantification indicators were additionally presented. The developed models are judged to be usable as a basic tool finding for guidelines because they can simultaneously quantify the amount of leakage calculated from the viewpoint of suppliers as well as the water availability of consumers when an earthquake hazard has occurred. Full article

(This article belongs to the Special Issue Resilient and Robust Water Distribution Systems: State-of-the-Art and Research Challenges)

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11 pages, 1902 KiB

Open AccessArticle

The Optimum Monitoring Location of Pressure in Water Distribution System

by Sanghyun Jun and Hyuk Jae Kwon

Water 2019, 11(2), 307; https://doi.org/10.3390/w11020307 - 12 Feb 2019

Cited by 3 | Viewed by 2852

Abstract

This study proposes two methods for the determination of optimum monitoring locations of pressure changes in a water distribution system. A sensitivity analysis method is used to calculate the pressure change in a junction due to the change in demand at other junctions. A pressure contribution analysis method is used to calculate the summation of pressure contribution of a junction due to the change in demand at another junction. These methods are applied to a small sample pipe network, pilot plant, and small distribution system for verification. Furthermore, unsteady analysis of the sample pipe network and an experiment in the pilot plant are conducted to verify the availability and accuracy of the proposed methods. To verify the methods, leakage at J-55 was artificially produced at the pilot plant. The pressure change was measured at five different combination groups of sensor locations. From the results, it was found that the top ranked group of sensor locations, J-116, J-140, J-22, and J-68, had the highest pressure contributions and sensitivity. The results of the newly developed methods for the determination of monitoring locations are in good agreement with the results of the unsteady analysis. Finally, the proposed methods are applied to a real distribution system of a small city as a test bed. It is found that the proposed methods for determining the monitoring locations of pressure changes in the water distribution system are useful and effective. Full article

(This article belongs to the Special Issue Resilient and Robust Water Distribution Systems: State-of-the-Art and Research Challenges)

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Other

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14 pages, 1459 KiB

Open AccessTechnical Note

Development of Multi-Objective Optimal Redundant Design Approach for Multiple Pipe Failure in Water Distribution System

by Young Hwan Choi and Joong Hoon Kim

Water 2019, 11(3), 553; https://doi.org/10.3390/w11030553 - 17 Mar 2019

Cited by 13 | Viewed by 3120

Abstract

This study proposes a multi-objective optimal design approach for water distribution systems, considering mechanical system redundancy under multiple pipe failure. Mechanical redundancy is applied to the system’s hydraulic ability, based on the pressure deficit between the pressure requirements under abnormal conditions. The developed design approach shows the relationships between multiple pipe failure states and system redundancy, for different numbers of pipe-failure conditions (e.g., first, second, third, …, tenth). Furthermore, to consider extreme demand modeling, the threshold of the demand quantity is investigated simultaneously with multiple pipe failure modeling. The design performance is evaluated using the mechanical redundancy deficit under extreme demand conditions. To verify the proposed design approach, an expanded version of the well-known benchmark network is used, configured as an ideal grid-shape, and the multi-objective harmony search algorithm is used as the optimal design approach, considering construction cost and system mechanical redundancy. This optimal design technique could be used to propose a standard for pipe failure, based on factors such as the number of broken pipes, during failure condition analysis for redundancy-based designs of water distribution systems. Full article

(This article belongs to the Special Issue Resilient and Robust Water Distribution Systems: State-of-the-Art and Research Challenges)

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