A New Method for Optimization of Water Distribution Networks While Considering Accidents

Optimization of water distribution networks can effectively reduce their annual cost, which includes the average investment for each year the operational costs and depreciation costs. However, the existing optimization models rarely directly consider the basic flow of each node in case of accidents, such as pipe bursts. Therefore, it is necessary to check the flow requirements under accident conditions. In order to deal with these drawbacks, two optimization models are established considering accident conditions: a single-objective optimization model considering annual cost as an economic objective, and a multi-objective optimization model with a reliability objective defined by the surplus water head. These models are solved based on the genetic algorithm, non-dominated sorting genetic algorithm-II algorithm and Levenberg-Marquardt iterative method. Applying two cases of a single pump station and a multi pump water station water supply, it is shown that the annual cost when considering the accident conditions is higher than that without considering the accident conditions. Moreover, the annual cost obtained with the multi-objective optimization model is slightly higher than that obtained with the single-objective optimization model. The cost is higher because the former model reduces the average surplus water head, which can improve the water distribution network reliability. Therefore, the model and optimization algorithm proposed in this paper can provide a general and fast optimization tool for water distribution network optimization.

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Identifying Critical Isolation Valves in a Water Distribution Network: A Socio-Technical Approach

10.21203/rs.3.rs-416140/v1 ◽

2021 ◽

Author(s):

Noha Abdel-Mottaleb ◽

Payman Ghasemi Saghand ◽

Mathews Wakhungu ◽

Hadi Charkhgard ◽

E. Christian Wells ◽

...

Keyword(s):

Water Distribution ◽

Water Distribution Network ◽

Distribution Networks ◽

Decision Makers ◽

Multi Objective Optimization ◽

Technical Approach ◽

Dual Representation ◽

Multi Objective ◽

Additional Information ◽

Single Objective

Abstract Isolation valves are critical for reliable functioning of water distribution networks (WDNs). However, it is challenging for utilities to prioritize valve rehabilitation and replacement given it is often unclear if certain valves are operable in a given WDN. This study uses the Gomory-hu tree of the segment-valve representation (or dual representation) of WDNs to obtain logical implications of inoperable valves (i.e., which segments would be isolated and merged unnecessarily due to valve inoperability). Multi-objective optimization is then used to identify the critical valves based on selected attributes (e.g., social vulnerability, flow volume) of segments that would be unnecessarily isolated as a result. This study developed three multi-objective formulations: first, deterministic; second, accounting for uncertainty; and third, accounting or both uncertainty and likelihood of failure of pipes within segments. Identified critical valves are compared between the three developed formulations and a method considering only a single objective. Results demonstrated that the multi-objective optimization provided additional information that can be used to discern valve importance for utilities in comparison with using a single objective. Further, though there was overlap between the results from the three formulations, the third formulation provided the most insight without overwhelming decision-makers with a large number of identified valves.

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A multi-objective optimization model for operation of intermittent water distribution networks

Water Science & Technology Water Supply ◽

10.2166/ws.2020.159 ◽

2020 ◽

Vol 20 (7) ◽

pp. 2630-2647

Author(s):

Mohammad Solgi ◽

Omid Bozorg-Haddad ◽

Hugo A. Loáiciga

Keyword(s):

Water Quality ◽

Water Supply ◽

Optimization Model ◽

Water Distribution ◽

Distribution Networks ◽

Water Distribution Networks ◽

Multi Objective Optimization ◽

Multi Objective ◽

Intermittent Operation ◽

Supply Interruption

Abstract Intermittent operation of water distribution networks (WDNs) is an undesirable yet inevitable strategy under some circumstances such as droughts, development, electricity blackouts, and water pollution, mostly in developing countries. Intermittent utilization of WDNs poses several disadvantages encompassing water quality degradation, deterioration of the water-distribution system, and extra operational and maintenance costs due to frequently interrupted supply, unfair water distribution among consumers, and reduction of system serviceability. This paper proposes a multi-objective optimization model to address the negative consequences of intermittent water shortages. The model is intended to maximize the quantitative and qualitative reliability and the fairness in water supply, and to minimize the frequency of supply interruption. The developed model also considers pragmatic limitations, water quality, water pressure, and supply reservoir's constraints to plan the operation of intermittent water distribution systems under water shortage. The model's efficiency is tested with a WDN in Iran and compared with a standard operation policy (SOP) for water distribution. According to the evaluated efficiency criteria concerning reliability, resiliency, and vulnerability of water quality and quantity of water supply, the developed model is superior to the SOP rule and improves the performance of the network under intermittent operation. In addition, the results demonstrate there is a tradeoff between the uniformity of water distribution and the frequency of supply interruption that shows operators’ and customers’ conflicting priorities.

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Multi-objective optimization for improving equity and reliability in intermittent water supply systems

Water Science & Technology Water Supply ◽

10.2166/ws.2020.066 ◽

2020 ◽

Vol 20 (5) ◽

pp. 1592-1603 ◽

Cited By ~ 1

Author(s):

Passwell Pepukai Nyahora ◽

Mukand Singh Babel ◽

David Ferras ◽

Andres Emen

Keyword(s):

Decision Making ◽

Water Supply ◽

Water Distribution ◽

Investment Decision ◽

Water Distribution Network ◽

Distribution Networks ◽

Water Supply Systems ◽

Multi Objective Optimization ◽

Multi Objective ◽

Intermittent Water Supply

Abstract Intermittent water systems suffer from several drawbacks such as unfair distribution among users, low reliability and poor water quality. Given limited water and financial resources, making decisions for improving intermittent water supply (IWS) becomes a complex process. The paths to continuous supply are a priori undefined, however, the provision of efficient service is crucial. In the scientific literature, limited research addresses how to improve intermittent systems, to enhance the current service while transitioning to continuous supply. A multi-objective optimization (MOO) tool using a genetic algorithm has been developed to assist in investment decision-making. This approach uses multiple cost-effective intervention options to maximize equity and reliability while minimizing cost implications in an IWS system. The costs in such interventions include expenditure on pipe replacement, booster pump and elevated tank installation. The approach was first tested on a benchmark Hanoi synthetic network, and then applied to the water distribution network of Milagro (Ecuador). The developed tool reveals the extent to which equity and reliability can be driving objectives, and how they can be factored into decision-making. The application of the MOO tool in intermittent systems in order to improve existing distribution networks with strategic infrastructure addition can provide greater equity and reliability.

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A study on appropriate investment of pipeline rehabilitation for water distribution network

Water Science & Technology Water Supply ◽

10.2166/ws.2005.0019 ◽

2005 ◽

Vol 5 (2) ◽

pp. 31-38

Author(s):

A. Asakura ◽

A. Koizumi ◽

O. Odanagi ◽

H. Watanabe ◽

T. Inakazu

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Water Supply ◽

Water Distribution ◽

Ad Hoc ◽

Distribution Network ◽

Water Distribution Network ◽

Distribution Networks ◽

Optimal Basis ◽

Model Case

In Japan most of the water distribution networks were constructed during the 1960s to 1970s. Since these pipelines were used for a long period, pipeline rehabilitation is necessary to maintain water supply. Although investment for pipeline rehabilitation has to be planned in terms of cost-effectiveness, no standard method has been established because pipelines were replaced on emergency and ad hoc basis in the past. In this paper, a method to determine the maintenance of the water supply on an optimal basis with a fixed budget for a water distribution network is proposed. Firstly, a method to quantify the benefits of pipeline rehabilitation is examined. Secondly, two models using Integer Programming and Monte Carlo simulation to maximize the benefits of pipeline rehabilitation with limited budget were considered, and they are applied to a model case and a case study. Based on these studies, it is concluded that the Monte Carlo simulation model to calculate the appropriate investment for the pipeline rehabilitation planning is both convenient and practical.

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Optimal placement of valves in a water distribution network with CLP(FD)

Theory and Practice of Logic Programming ◽

10.1017/s1471068411000275 ◽

2011 ◽

Vol 11 (4-5) ◽

pp. 731-747 ◽

Cited By ~ 13

Author(s):

MASSIMILIANO CATTAFI ◽

MARCO GAVANELLI ◽

MADDALENA NONATO ◽

STEFANO ALVISI ◽

MARCO FRANCHINI

Keyword(s):

Logic Programming ◽

Distribution Systems ◽

Water Distribution ◽

Distribution Network ◽

Real Life ◽

Water Distribution Network ◽

Distribution Networks ◽

Constraint Logic Programming ◽

Optimal Placement ◽

Isolation System

AbstractThis paper presents a new application of logic programming to a real-life problem in hydraulic engineering. The work is developed as a collaboration of computer scientists and hydraulic engineers, and applies Constraint Logic Programming to solve a hard combinatorial problem. This application deals with one aspect of the design of a water distribution network, i.e., the valve isolation system design. We take the formulation of the problem by Giustolisi and Savić (2008 Optimal design of isolation valve system for water distribution networks. InProceedings of the 10th Annual Water Distribution Systems Analysis Conference WDSA2008, J. Van Zyl, A. Ilemobade, and H. Jacobs, Eds.) and show how, thanks to constraint propagation, we can get better solutions than the best solution known in the literature for the Apulian distribution network. We believe that the area of the so-calledhydroinformaticscan benefit from the techniques developed in Constraint Logic Programming and possibly from other areas of logic programming, such as Answer Set Programming.

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Towards Development of an Optimization Model to Identify Contamination Source in a Water Distribution Network

Water ◽

10.3390/w10050579 ◽

2018 ◽

Vol 10 (5) ◽

pp. 579 ◽

Cited By ~ 14

Author(s):

Oluwaseye Adedoja ◽

Yskandar Hamam ◽

Baset Khalaf ◽

Rotimi Sadiku

Keyword(s):

Optimization Model ◽

Water Distribution ◽

Distribution Network ◽

Water Distribution Network ◽

Contamination Source

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Multi-objective optimization to the rehabilitation of a water distribution network

Advances in Water Supply Management ◽

10.1201/noe9058096081.ch34 ◽

2003 ◽

Author(s):

L Reis ◽

I Carrijo ◽

P Cheung

Keyword(s):

Water Distribution ◽

Distribution Network ◽

Water Distribution Network ◽

Multi Objective Optimization ◽

Multi Objective

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Technical note: Problem specific variators in a genetic algorithm for the optimization of drinking water networks

10.5194/dwes-2018-21 ◽

2018 ◽

Author(s):

Karel van Laarhoven ◽

Ina Vertommen ◽

Peter van Thienen

Keyword(s):

Drinking Water ◽

Real World ◽

Water Distribution ◽

Water Distribution Network ◽

Distribution Networks ◽

Technical Note ◽

Practical Implementation ◽

Utility Level ◽

Water Utility ◽

Drinking Water Distribution

Abstract. Genetic algorithms can be a powerful tool for the automated design of optimal drinking water distribution networks. Fast convergence of such algorithms is a crucial factor for successful practical implementation at the drinking water utility level. In this technical note, we therefore investigate the performance of a suite of genetic variators that was tailored to the optimisation of a least-cost network design. Different combinations of the variators are tested in terms of convergence rate and the robustness of the results during optimisation of the real world drinking water distribution network of Sittard, the Netherlands. The variator configurations that reproducibly reach the furthest convergence after 105 function evaluations are reported. In the future these may aid in dealing with the computational challenges of optimizing real world networks.

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Proposal of optimal operation strategy applied to water distribution network with statistical approach

Ambiente e Agua - An Interdisciplinary Journal of Applied Science ◽

10.4136/ambi-agua.2455 ◽

2020 ◽

Vol 15 (2) ◽

pp. 1

Author(s):

Alex Takeo Yasumura Lima Silva ◽

Fernando Das Graças Braga da Silva ◽

André Carlos da Silva ◽

José Antonio Tosta dos Reis ◽

Claudio Lindemberg de Freitas ◽

...

Keyword(s):

Genetic Algorithms ◽

Water Distribution ◽

Distribution Network ◽

Water Distribution Network ◽

Distribution Networks ◽

Optimal Operation ◽

Optimization Techniques ◽

Experimental Techniques ◽

Computational Optimization ◽

Depth Analysis

Inefficiency of sanitation companies’ operation procedures threatens the population’s future supplies. Thus, it is essential to increase water and energy efficiency in order to meet future demand. Optimization techniques are important tools for the analysis of complex problems, as in distribution networks for supply. Currently, genetic algorithms are recognized by their application in literature. In this regard, an optimization model of water distribution network is proposed, using genetic algorithms. The difference in this research is a methodology based on in-depth analysis of results, using statistics and the design of experimental tools and software. The proposed technique was applied to a theoretical network developed for the study. Preliminary simulations were accomplished using EPANET, representing the main causes of water and energy inefficiency in Brazilian sanitation companies. Some parameters were changed in applying this model, such as reservoir level, pipe diameter, pumping pressures, and valve-closing percentage. These values were established by the design of experimental techniques. As output, we obtained the equation of response surface, optimized, which resulted in values of established hydraulic parameters. From these data, the obtained parameters in computational optimization algorithms were applied, resulting in losses of 26.61%, improvement of 16.19 p.p. with regard to the network without optimization, establishing an operational strategy involving three pumps and a pressure-reducing valve. We conclude that the association of optimization and the planning of experimental techniques constitutes an encouraging method to deal with the complexity of water-distribution network optimization.

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