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

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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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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Appraisal of water quality indices for service reservoirs in water distribution networks

Water Science & Technology ◽

10.2166/wst.2020.215 ◽

2020 ◽

Vol 81 (8) ◽

pp. 1606-1614 ◽

Cited By ~ 1

Author(s):

M. S. Nyirenda ◽

T. T. Tanyimboh

Keyword(s):

Water Quality ◽

Water Distribution ◽

Distribution Network ◽

Water Distribution Network ◽

Distribution Networks ◽

Sampling Point ◽

Quality Indices ◽

Water Quality Indices ◽

State Of Water ◽

Pollution Loads

Abstract The use of water quality indices to aggregate pollution loads in rivers has been widely studied, with researchers using various sub-indices and aggregation methods. These have been used to combine various quality variables at a sampling point in a river into an overall water quality index to compare the state of water quality in different river reaches. Service reservoirs in a water distribution network, like rivers, have complex mixing mechanisms, are subjected to various water quality variables and are variably sized and sited. Water quality indices and the relevant sub-indices are formulated here and applied to service reservoirs within a water distribution network. This is in an attempt to compare holistically the performance of service reservoirs in solutions of optimisation algorithms with regards to water quality.

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A Framework for Identifying the Critical Region in Water Distribution Network for Reinforcement Strategy from Preparation Resilience

Sustainability ◽

10.3390/su12219247 ◽

2020 ◽

Vol 12 (21) ◽

pp. 9247

Author(s):

Mingyuan Zhang ◽

Juan Zhang ◽

Gang Li ◽

Yuan Zhao

Keyword(s):

Water Distribution ◽

Large Scale ◽

Distribution Network ◽

Water Distribution Network ◽

Distribution Networks ◽

Water Shortage ◽

Hydraulic Control ◽

Urban Function ◽

Network Disruption ◽

Critical Regions

Water distribution networks (WDNs), an interconnected collection of hydraulic control elements, are susceptible to a small disturbance that may induce unbalancing flows within a WDN and trigger large-scale losses and secondary failures. Identifying critical regions in a water distribution network (WDN) to formulate a scientific reinforcement strategy is significant for improving the resilience when network disruption occurs. This paper proposes a framework that identifies critical regions within WDNs, based on the three metrics that integrate the characteristics of WDNs with an external service function; the criticality of urban function zones, nodal supply water level and water shortage. Then, the identified critical regions are reinforced to minimize service loss due to disruptions. The framework was applied for a WDN in Dalian, China, as a case study. The results showed the framework efficiently identified critical regions required for effective WDN reinforcements. In addition, this study shows that the attributes of urban function zones play an important role in the distribution of water shortage and service loss of each region.

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Sensor placement for leak detection and location in water distribution networks

Water Science & Technology Water Supply ◽

10.2166/ws.2014.037 ◽

2014 ◽

Vol 14 (5) ◽

pp. 795-803 ◽

Cited By ~ 20

Author(s):

R. Sarrate ◽

J. Blesa ◽

F. Nejjari ◽

J. Quevedo

Keyword(s):

Water Distribution ◽

Structural Model ◽

Distribution Network ◽

Pressure Sensors ◽

Water Distribution Network ◽

Leak Detection ◽

Distribution Networks ◽

Optimization Strategy ◽

Sensor Configuration ◽

Leak Detection And Location

The performance of a leak detection and location algorithm depends on the set of measurements that are available in the network. This work presents an optimization strategy that maximizes the leak diagnosability performance of the network. The goal is to characterize and determine a sensor configuration that guarantees a maximum degree of diagnosability while the sensor configuration cost satisfies a budgetary constraint. To efficiently handle the complexity of the distribution network an efficient branch and bound search strategy based on a structural model is used. However, in order to reduce even more the size and the complexity of the problem the present work proposes to combine this methodology with clustering techniques. The strategy developed in this work is successfully applied to determine the optimal set of pressure sensors that should be installed in a District Metered Area in the Barcelona water distribution network.

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Study on Safety Evaluation Method for Water Distribution Networks Based on LS-SVM

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.5003 ◽

2011 ◽

Vol 243-249 ◽

pp. 5003-5008

Author(s):

Zhi Tao Wang ◽

Jing Yu Su ◽

Wei Wang

Keyword(s):

Water Distribution ◽

Distribution Network ◽

Water Distribution Network ◽

Distribution Networks ◽

Influential Factors ◽

Water Distribution Networks ◽

Security Level ◽

Urban Water ◽

Ann Model ◽

Svm Model

To evaluate the security of urban water distribution network, one model based on LS-SVM was put forth. On the basis of summary and analysis of influential factors for urban water distribution network security, a set of indexes used in the evaluation model above was constructed. The nonlinear mapping between the water distribution networks security classification and its conditions were learned from the finite samples and a water distribution network example was simulated using this model. In addition, the BP ANN model was used to simulate the same example. Through the analysis of the result of the actual security level, the security level acquired by the LS-SVM model and BP ANN model, it may be found that the result acquired by the LS-SVM model has high accuracy, and may used in actual engineering.

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Hydraulic performance of post-earthquake water distribution networks based on head driven simulation method

Water Science & Technology Water Supply ◽

10.2166/ws.2013.141 ◽

2013 ◽

Vol 13 (5) ◽

pp. 1281-1288 ◽

Cited By ~ 5

Author(s):

A. Mani ◽

M. Tabesh ◽

M. R. Zolfaghari

Keyword(s):

Urban Areas ◽

Water Distribution ◽

Performance Indicator ◽

Distribution Network ◽

Water Distribution Network ◽

Simulation Method ◽

Distribution Networks ◽

Hydraulic Performance ◽

Water Distribution Networks ◽

Actual Performance

Water distribution networks are one of the most important infrastructures in urban areas. Evaluating their real hydraulic performance after being damaged by earthquake loadings is crucial for future planning. In this study, pipeline damage caused by seismic wave propagation is modelled using relationships obtained from 1994 Northridge earthquake. Damaged network is hydraulically analysed using the head driven simulation method (HDSM). This analysis helps to obtain actual performance of the water distribution network damaged by seismic waves, without the usual need to handle negative nodal pressures generated from demand driven simulation method. Pressure performance indicator and the total leakage of the network are used as indicators to show the hydraulic performance of the system. Comparison of the damages from different seismic scenarios and the hydraulic indicators of the network, illustrate the probable condition of the water distribution network after the earthquake. The proposed methodology is applied on a reservoir zone of the Tehran water distribution network. The results indicate the degree of damage in terms of pipe burst and leak points in this network.

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Application of Routine Calibration of Real Water Supply Network with Adjustment of Demand Roughness Parameters Driven by Applied Pressure Real Network of Brazil

10.29007/z3hq ◽

2018 ◽

Author(s):

Fernando Das Graças Braga Da Silva ◽

Thaisa Dias Goulart ◽

Regina Mambeli Barros

Keyword(s):

Water Distribution ◽

Distribution Network ◽

Applied Pressure ◽

Water Distribution Network ◽

Distribution Networks ◽

Calibration Method ◽

Decision Variable ◽

Demand Model ◽

Real Network ◽

Search Tool

The calibration of water distribution networks is one way to perform such procedures in hydraulic models, but several are the difficulties encountered in calibrating a real network. This work proposes the improvement of modules of the calibration method proposed by Silva (2003), where using the genetic algorithm (GA) search tool, the author calibrates a real water distribution network of a Brazilian city, adjusting parameters mainly from roughness and coefficient of leakage. The enhancement of GA is the introduction of a new decision variable, the nodal demand, which assigns demand values to nodes according to the pressure-driven demand model of Tucciarelli, Criminisi and Termini (1999). The tests of the GAs implemented are tested for this real water distribution network presented by Silva (2003). The effect of the improvement on the calibration results was significant for the network, but the need for more in-depth studies, which are of course required for the application of new algorithms in real-scale networks.

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Technical note: Graph theory-based heuristics to aid in the implementation of optimized drinking water network sectorization

10.5194/dwes-2021-11 ◽

2022 ◽

Author(s):

Marius Møller Rokstad ◽

Karel Antonie van Laarhoven

Keyword(s):

Drinking Water ◽

Water Distribution ◽

Mathematical Problem ◽

Distribution Network ◽

Large City ◽

Distribution Networks ◽

Technical Note ◽

Optimization Techniques ◽

Actual Distribution ◽

Drinking Water Distribution

Abstract. Drinking water distribution networks form an essential part of modern-day critical infrastructure. Sectorizing a network into district metered areas is a key technique for pressure management and water loss reduction. Sectorizing an existing network from scratch is, however, an exceedingly complex design task that designs in a well-studied general mathematical problem. Numerical optimization techniques such as evolutionary algorithms can be used to search for near-optimal solutions to such problems, but doing so within a reasonable timeframe remains an ongoing challenge. In this work, we introduce two heuristic tricks that use information of the network structure and information of the operational requirements of the drinking water distribution network to modify the basic evolutionary algorithm used to solve the general problem. These techniques not only reduce the time required to find good solutions, but also ensure that these solutions better match the requirements of drinking water practice. Both techniques were demonstrated by applying them in the sectorization of the actual distribution network of a large city.

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An investigation of the possible scenarios for the optimal locating of quality sensors in the water distribution networks with uncertain contamination

Journal of Water and Health ◽

10.2166/wh.2020.099 ◽

2020 ◽

Vol 18 (5) ◽

pp. 704-721

Author(s):

Hamideh Jafari ◽

Taher Rajaee ◽

Sara Nazif

Keyword(s):

Water Consumption ◽

Water Distribution ◽

Distribution Network ◽

Water Distribution Network ◽

Distribution Networks ◽

Contaminated Water ◽

Nsga Ii ◽

Minimum Number ◽

Contamination Event ◽

Population Ratio

Abstract One of the ways to reduce the risk of contaminated water consumption is to optimally locate the quality sensors. These sensors warn users in the case of contamination detection. Analyzing the actual conditions of the contamination which enters the network is faced with many uncertainties. These uncertainties include the dose of contamination, time and location of its entry which have received less attention. Also, the uncertainty in the nodes' water demand causes changes in the distribution and contamination diffusion within the network. The main impetus of the present study is to determine the optimal quality sensor locations in the water distribution network in order to reduce the damage caused by contaminated water consumption prior to the contamination event detection. For this purpose, a parameter is defined as the maximum possible damage for calculating which the vulnerability and importance of the nodes have been considered in addition to the uncertainties in the location and time of the contamination entry. The importance of each node differs from that of other ones. Ranking the importance of the nodes is influenced by both land use and covered population ratio. In this study, six scenarios are defined for the contamination event in the water distribution network. These scenarios consider the effects of varying pollutant dose and the contamination input from nodes which are prone to its entry. Also, the NSGA-II has been utilized in order to minimize the damage with minimum number of sensors. The proposed model is evaluated on a real network in Iran. The results indicate that adding only one or two contamination warning sensors to the proposed locations can lead to the decreasing damage caused by the contaminated water consumption from 54 to 82%. According to the proposed method, the best answer for scenarios 1–6 was obtained for 7, 6, 6, 2, 2 and 2 sensors, respectively. The results showed that the slope of the pollution rate diagram does not change much from 6 sensors upwards in the first three scenarios, and from 4 sensors upwards in the second three scenarios. In scenarios 1–3, with 7, 6 and 6 sensors, respectively, in different nodes, the best placement is for 203–224 equivalent attack population, and in scenarios 4–6, with sensors in nodes 4 and 43, the best placement is for 225–279 equivalent attack population.

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