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Analysis of Economic Leakage Level and Infrastructure Leakage Index Indicator by Applying Active Leakage Control
(Asce-Amer Soc Civil Engineers, 2021) Yilmaz, Salih; Firat, Mahmut; Ates, Abdullah; Ozdemir, Ozgur
Active leakage control (ALC) has an important place in the management and prevention of leaks in water or/and gas distribution systems. However, cost-benefit components and the amount of economically recoverable leakage should be analyzed and determined, respectively, for the effective implementation of this method. In this study, an analysis of the cost-benefit components of the ALC method is presented for determining the amount of recoverable leakage and evaluating changes in the infrastructure leakage index (ILI) under the ALC method. An economic analysis of ALC was made for nine regions with different characteristics and benefits. System performance was evaluated according to ILI by calculating cost. The economically recoverable leakage under ALC, representing the maximum amount of water that could be economically saved to the system by the ALC method in the district metered areas (DMAs), were calculated. The ILI parameter, which has quite an important place in the performance of water distribution systems (WDSs), may be insufficient on its own for determining whether application of ALC will be economical in a region. The results showed that application of ALC method would not be economical, especially in regions in which unit water production costs are low and the number of customers per unit length and leakage are low.
Analysis of floods from natural channels in urban areas and creation of risk map: Malatya province case
(Pamukkale Univ, 2019) Kilic, Selami; Ozdemir, Ozgur; Firat, Mahmut
In this study, flood simulation analysis was carried out for the natural channels in the urban area and a risk map of flood waters was formed. For this purpose, Horata channel in Malatya city center was selected as the application area where there are a total of four streams, which have the flood risk potential. The flood events observed in the past were investigated and the factors that cause it were evaluated. Flood hydrographs were obtained for 50, 100 and 500 year return periods for the Horata channel. Info-works ICM was used for flood simulation and flood analysis was performed for different recurrence periods. It was observed that stream sections were inadequate and settlement areas would be adversely affected especially for the return period of 500 years. As a result, flood propagation maps were created for each case and the affected areas were determined. According to the results of these analyzes, the regions where the risk of floods are high can be listed as follows, especially where the natural flow is disturbed, the section is constricted for bridging, the areas where meandering are formed, regions where the section is insufficient.
Analysis of network useful life and cost-benefits for sustainable water management
(Yildiz Technical Univ, 2024) Yilmaz, Salih; Firat, Mahmut; Ates, Abdullah
Main lines and service connections in distribution systems are damaged due to various factors. The leakage volume, operating and repair costs increase depending on the density of damage. The cost-benefit and economic life analysis should be done for network renewal in distribution systems. In this study, a useful life analysis model was developed for pipes serving in distribution systems. The total number of failures in water distribution systems, failure repair costs, pipe diameter and material and leakage rates in the existing system and network characteristics are considered. The developed model was applied in 9 isolated regions with different properties in the application area. The useful lives have varied depending on the characteristics of the regions. The number of failures and the amount of water losses, as well as the length of the network and the type of new pipe play serious role in useful life analysis. Especially, it was observed that the type of pipe material to be used in network renewal has an effect on the useful life. It is thought that this study will constitute a reference for technical personnel, especially in deciding to renew the network.
Analysis of temperature series: estimation of missing data and homogeneity test
(Wiley-Blackwell, 2012) Firat, Mahmut; Dikbas, Fatih; Koc, A. Cem; Gungor, Mahmud
In this study, missing value analysis and homogeneity tests were applied on the 267 meteorological stations having temperature records throughout Turkey. The monthly and annual mean temperature data of stations operated by the Turkish State Meteorological Service (DMI) for the period 1968-1998 were considered. For each station, each month was analysed separately and the stations with more than 5 years missing values were eliminated. The missing values of the stations were extrapolated by the Expectation Maximization (EM) method using the data of the nearest gauging station (reference station). In consequence of the analysis, annual mean temperature data are obtained by using the monthly values. These data have to be hydrologically/statistically reliable if they are to be used in later hydrological, meteorological, climate change and estimation studies. For this reason, the Standard Normal Homogeneity Test (SNHT), the (Swed-Eisenhart) Runs Test and the Pettitt homogeneity test were applied to detect inhomogeneities in the annual mean temperature series. Each test was evaluated separately and inhomogeneous stations were determined. Copyright (C) 2011 Royal Meteorological Society
Analysis of the effect of pressure control on leakages in distribution systems by FAVAD equation and field applications
(Iwa Publishing, 2021) Ozdemir, Ozgur; Firat, Mahmut; Yilmaz, Salih; Usluer, Mustafa
Pressure has an important effect on the occurrence of failures/leaks in water distribution systems (WDSs) or the change of leakage in existing leakages. For this reason, monitoring the pressure is important especially for analyzing the changes in the day and night, determining the fluctuations and applying pressure management (PM) to ensure normal operating conditions. In this study, the effect of pressure on water losses and minimum night flow (MNF) was carried out according to the Fixed and Varied Area Discharge (FAVAD) approach, which allows the amount of leakage to be calculated based on the change in pressure and field tests. The minimum flow rate and potential leakage were determined under the network operating conditions before the pressure control in a region. Then, considering the features of the region, pressure was reduced with the pressure control system and MNFs and leaks were monitored. By reducing the pressure from 9.10 bar to 3.2 bar in the region, the MNF rate was reduced from 6.95 I/s to 3.29 I/s. The daily water savings in the system inlet volume is 78.44 m(3)/day and the annual saving is 28,624 m(3)/year. The results obtained are very important for practitioners in terms of implementing PM in the field.
Analyzing the economic water loss level with a discrete stochastic optimization algorithm by considering budget constraints
(Iwa Publishing, 2022) Yilmaz, Salih; Firat, Mahmut; Ate, Abdullah; Ozdemir, Ozgur
Water losses in water distribution systems (WDSs) cause inefficiency of water resources and increase operating costs. Water loss management (WLM) methods generally have high initial investment and operating costs. However, the budget planned within the scope of WLM in administrations is generally limited. Therefore, the most appropriate method should be determined by considering the budget conditions and cost-benefit analysis. The aim of this study is to propose a new economic water loss level (EWLL) model in WDSs with the different budget constraints of 5, 15 and 20% of the annual income. This EWLL model was developed by the discrete stochastic optimization algorithm. The EWLL and economically recoverable leakage volumes were determined by considering the budget constraints. Moreover, the most appropriate methods were determined to reach the EWLL values defined according to the budget constraints. The EWLL was calculated as 8.62% by the optimization model without budget constraints. Moreover, the EWLL values with budget constraints of 5, 15 and 20% of the annual income were determined as 56.82, 21.14 and 18.02%, respectively. This EWLL model will make a significant contribution to the annual planning in WLM depending on the budget constraints of the administrations.
Classification of Annual Precipitations and Identification of Homogeneous Regions using K-Means Method
(Turkish Chamber Civil Engineers, 2012) Firat, Mahmut; Dikbas, Fatih; Koc, Abdullah Cem; Gungor, Mahmud
Classification of Annual Precipitations and Identification of Homogeneous Regions using K-Means Method Reliable and correct estimation of hydrological and meteorological processes is one of the major problems in regions with insufficient hydrologic information and data. The classification of the hydrological variables and determination of homogeneous regions are the most important steps of regional studies. The purpose of this study is to classify the annual total precipitation series and to identify the homogeneous regions by K-Means method. The K-means method, which is the simplest and most commonly used clustering method, divides a data set into clusters by minimizing the sum of the Euclidean distance between each feature vector and its closest cluster centre. The annual precipitation records and longitude, latitude and altitude values obtained of 188 stations operated by the National Meteorology Works (DMI) in Turkey were considered for clustering analysis. The number of clusters was determined as 7 by means of clustering analysis. Moreover, the regional homogeneity test was applied for testing the homogeneity of regions.
Classification of precipitation series using fuzzy cluster method
(Wiley-Blackwell, 2012) Dikbas, Fatih; Firat, Mahmut; Koc, A. Cem; Gungor, Mahmud
The identification of hydrologically homogeneous regions is one of the most important steps of regional frequency analysis. The hydrologically homogeneous regions should be determined using cluster analysis instead of the geographically close regions or stations. In this study, fuzzy cluster method (Fuzzy C-Means: FCM) is applied to classify the precipitation series and identify the hydrologically homogeneous groups. The choice of appropriate cluster method and the variables that will be used according to the data of the basin is also very important. In the context of this study, total precipitation data of stations operated by National Meteorology Works (DMI) in Turkish basins for cluster analysis are used. The optimal number of groups is determined as six, based on different performance evaluation indexes. Regional homogeneity tests based on L-moments method are applied to check homogeneity of these six regions identified by cluster analysis. Regional homogeneity test results show that regions defined by FCM method are sufficiently homogeneous for regional frequency analysis. According to the results, FCM method is recommended for classifying the precipitation series and for identifying the hydrologically homogenous regions. Copyright (c) 2011 Royal Meteorological Society
Comparative analysis of neural network techniques for predicting water consumption time series
(Elsevier Science Bv, 2010) Firat, Mahmut; Turan, Mustafa Erkan; Yurdusev, Mehmet Ali
Monthly water consumption time series have been predicted using a series of Artificial Neural Network (ANN) techniques including Generalized Regression Neural Networks (GRNN), Cascade Correlation Neural Network (CCNN) and Feed Forward Neural Networks (FFNN). One hundred and eight data sets for the city of Izmir, Turkey are used for a number of ANN modeling exercises. Several ANN models depending on the combination of antecedent values of water consumption records are constructed and the best fit input structure is investigated. The performance of ANN models in training and testing stages are compared with the observed water consumption values to identify the best fit forecasting model based upon a number of selected performance criteria. (C) 2010 Elsevier B.V. All rights reserved.
Defining cost standard and new algorithm for economic leakage level components in water loss management
(Univ Estadual Maringa, Pro-Reitoria Pesquisa Pos-Graduacao, 2022) Yilmaz, Salih; Ates, Abdullah; Firat, Mahmut; Ozdemir, Ozgur
Methods and tools used to reduce leakage in distribution systems are often time consuming and costly and require special requirements. Therefore, cost-benefit analysis is very important for basic reduction methods applied in water loss management. In this study, cost and benefit analysis standards were developed for basic methods such as pressure management, number of teams, and pipe rehabilitation and active leakage control, in managing leakages. Moreover, a new cost algorithmic structure was developed and the economically recoverable water amount was determined by applying calculation tool developed to make detailed analyzes systematically and accurately. The most important advantage of this study is the development of an economic analysis model and algorithmic structure for basic reduction methods according to field data. It is thought that the cost analysis and algorithmic structures developed will make a significant contribution to the economic leakage level analysis and serve as a reference for sustainable water loss management.
Defining Homogeneous Regions for Streamflow Processes in Turkey Using a K-Means Clustering Method
(Springer Heidelberg, 2013) Dikbas, Fatih; Firat, Mahmut; Koc, A. Cem; Gungor, Mahmud
The major problem in ungauged basins for planning and management of water resources projects is to estimate the flood magnitudes and frequencies. The identification of hydrologically homogeneous regions is one of the most important steps of regional frequency analysis. In this study, K-Means clustering method is applied to classify the maximum annual flows and identify the hydrologically homogeneous groups. For this aim, the annual maximum river flows, coefficient of variation and skewness of annual maximum river flows, latitude and longitude at 117 stations operated by the General Directorate of Electrical Power Resources Survey and Development Administration throughout Turkey are used. The optimal number of groups was determined as seven. Regional homogeneity test based on L-moments method is applied to check homogeneity of these seven regions identified by clustering analysis. The results show that regions defined by K-Means method can be used for regional flood frequency analysis. According to the results, K-Means method is recommended to identify the hydrologically homogeneous regions for regional frequency analysis.
DEFINING THE OPTIMUM PRESSURE FOR ACTIVE LEAKAGE CONTROL EFFICIENCY BY CONSIDERING ECONOMIC CRITERIA
(Parlar Scientific Publications (P S P), 2021) Yilmaz, Salih; Firat, Mahmut; Ates, Abdullah; Ozdemir, Ozgur
The main purpose of this study is to determine the optimum pressure level by considering the economic criteria in case of applying pressure management and acoustic listening method, which are the most basic leakage reduction methods. For this purpose, optimum pressure levels were determined in the pilot regions selected and benefits to be obtained were discussed. The useful flow rate for ALC application in 4 regions was obtained as zero (0). In these DMAs, it was observed that the benefit to be obtained by applying only pressure management in these regions is more than the benefit that can be obtained from applying acoustic listening and pressure management together. Due to low water production costs, determining an active reduction strategy in the region will have uneconomic consequences for the Administration. Therefore, if there is no shortage of water resources, it would be a more ideal strategy to apply PM for DMA4. The results obtained from this study will constitute a reference within the scope of determining the optimum pressure level that will provide maximum benefit economically in the network when PM and ALC methods are used together.
Determination of Economic Leakage Level with Optimization Algorithm in Water Distribution Systems
(World Scientific Publ Co Pte Ltd, 2021) Firat, Mahmut; Yilmaz, Salih; Ates, Abdullah; Ozdemir, Ozgur
It is necessary to set the most appropriate targets in water loss management (WLM) and to choose the most economically and technically suitable method to achieve these targets. The aim of this work is to define the level of economic leakage with the optimization algorithm in sustainable WLM, considering the system components, requirements and costs of the methods. For this purpose, a new model based on discrete stochastic optimization has been developed to determine the most appropriate values of the pressure level and the number of teams. After the system components were entered into the model, the optimal values of parameters were determined according to the problem-specific defined objective function. It was calculated that the pressure should be reduced from 40 m to 25.30 m, and the number of teams was 4 for the sample system. The Economic Leakage Level for the system was calculated as 145.85 m(3)/day in volume and 11.9% in percentage.
Determination of economic loss levels in water distribution systems with different network conditions by a district stochastic optimization algorithm
(Iwa Publishing, 2023) Yilmaz, Salih; Ates, Abdullah; Firat, Mahmut; Ozdemir, Ozgur; Cinal, Huseyin
Water losses in water distribution systems reach significant rates depending on the network characteristics. Various methods, which have initial investment and operating costs have been applied to reduce these losses. Therefore, appropriate and applicable methods should be preferred by considering the network characteristics. The aim of this study is to determine the economic loss level with an optimization algorithm for utilities with different network characteristics, water production, operating costs and institutional capacity. Three pilot utilities with different system characteristics and water loss components were selected as application areas. The non-revenue water rates are currently calculated as 57, 50 and 37%, respectively. The economic loss levels in the pilot utilities were calculated as 29, 16 and 23% with the optimization model. Moreover, the most appropriate methods to be applied according to the conditions of the utilities were determined in order to reach these defined economic loss levels. It is thought that the results obtained from this study will be a reference for the development of sustainable water loss management strategies and their implementation in the field.
DETERMINATION OF PRIORITY REGIONS FOR REHABILITATION IN WATER NETWORKS BY MULTIPLE CRITERIA DECISION MAKING METHODS
(Yildiz Technical Univ, 2020) Gul, Seymanur; Firat, Mahmut
Network rehabilitation and pipe material management could be shown as an important economic load for the Water Utility. For this reason, detailed analysis should be made and the worst regions should be determined before applying the methods. In this study, it is aimed to determine the priority regions for rehabilitation in distribution systems in order to prevent water losses. For this aim, a total of 28 factors that can be measured, applied and representing the problem were determined in the application area. Weight coefficients were calculated with the ENTROPY method to determine the degree of influence of these factors in decision making. The highest weight coefficient was obtained for the unreported leakages determined by active leakage control. ELCETRE I and PROMETHEE II methods were applied in determining the priority regions in rehabilitation. According to the results obtained with the ELECTRE I method, DMA 13, DMA 11, DMA 12, DMA 14 and DMA 5 regions were determined as the first 5 regions with rehabilitation priority. On the other hand, according to the PROMETHEE II method, the first 5 regions with rehabilitation priority were DMA 13, DMA 11, DMA 12, DMA 8 and DMA 15. When the results obtained by these two methods are compared, it is seen that the first region with priority of rehabilitation is similar. Thus, it is possible to provide a solution that requires investment priority and aims to increase water resource and economic efficiency. It is thought that the results obtained in this study will serve as a reference in terms of network and water loss management.
Developing a management and operation model for water and wastewater components using the equilibrium optimization algorithm
(Iwa Publishing, 2024) Kilic, Selami; Ates, Abdullah; Firat, Mahmut; Yilmaz, Salih
A novel optimization model was developed using the equilibrium optimization algorithm to define the most appropriate management process according to the current state of urban water components in utilities. The basis of the optimization model is the current status analysis and management system, which consists of 11 main headings and 231 components. This model is applied for three utilities, and the results are presented in comparison with real-time data. Currently, the number of components with 0 or 1 score is 28, 19 and 69, respectively. The current average scores of the components in the utilities were obtained as 2.84, 3.43 and 2.48, respectively. Then, the improvement process of these components is optimized by the equilibrium optimization algorithm. The most appropriate targets were defined as 3.90, 4.15 and 3.71, respectively, with the optimization algorithm by considering the current scores in the utilities. The target scores for water supply, wastewater collection and treatment components are determined as 3.81, 4.05 and 3.84 for utility I; 4.03, 4.18 and 4.22 for utility II; and 3.51, 3.56 and 4.05 for utility III. The proposed model will be a reference for defining the most appropriate target and determining the management process.
Developing a model to evaluate current practice level of key data used in water loss management
(Pamukkale Univ, 2023) Bozkurt, Cansu; Firat, Mahmut; Ates, Abdullah
Various methods and processes are applied in order to manage losses in water distribution systems. In order to apply these methods and achieve the expected benefits, the basic data in the system should be measured and monitored regularly. In this study, a new model was developed to analyze and evaluate the current levels of basic data required for the sustainable execution of water loss management processes. For this, a total of 18 basic components covering water loss management were considered. A scoring structure has been developed to evaluate the current status and application level of these components. In this scoring structure, the components are scored gradually to define the current level of application. The developed model was applied to three water utilities and tested with real field data. The current situation, weaknesses and strengths of each administration are defined within the scope of basic data. Targets to be achieved gradually for each component were determined based on these analyzes. It is thought that this study will constitute a reference for decision makers and technical personnel in administrations, especially in water loss management.
Development and Implementation of a Novel Assessment System for Water Utilities in Strategic Water Loss Management
(Asce-Amer Soc Civil Engineers, 2023) Firat, Mahmut; Bozkurt, Cansu; Ates, Abdullah; Yilmaz, Salih; Ozdemir, Ozgur
Numerous methods and tools have been proposed to manage water losses in water distribution systems. These methods generally involve time-consuming and costly processes. Since the dynamic structure of each system is different, the applicability of the methods should be analyzed before applying the methods. In this study, a novel system is developed to analyze the current condition of utility and to assess the data quality and current implementation level of water loss management (WLM) practices. This system consists of a total of 144 WLM components under eight main categories. Pilot utilities are selected to test the feasibility of the developed model and analyze its behavior in the field. Weaknesses and strengths within the scope of WLM are defined separately for each utility. It was understood that the model developed takes into account the dynamic structure of each utility, is applicable in the field, and presents the current condition in a realistic way. It is thought that the developed model will create a reference, especially for practitioners and decision makers in the field, and will provide important benefits in the scope of WLM.
Development of a new comprehensive framework for the evaluation of leak management components and practices
(Iwa Publishing, 2022) Bozkurt, Cansu; Firat, Mahmut; Ates, Abdullah
Leaks cause significant operational problems in water distribution systems (WDSs). The methods for managing leaks are time-consuming and costly. Therefore, the suitability and applicability of water loss management (WLM) methods should be analyzed. In this study, a new comprehensive framework was proposed using the scoring table to evaluate and highlight the reliability of data and to analyze the current application level of leakage management practices in WDSs. The developed framework consists of 60 sub-components determined to cover the WLM practices. A scoring structure was created to analyze these sub-components in measurable criteria. The developed framework was applied to three pilot administrations, and the results were discussed. The data quality (quite good, good, doubtful, poor, and quite poor) is classified according to the application level of the leakage management practices. The data quality of leakage management components and the application levels of practices are at good level in Administrations I and II and at moderate level in Administration III. The weaknesses and strengths in administrations were defined in the scope of leakage management, and the components that need improvement are determined dynamically. This framework will provide more accurate data for sustainable leakage management in the administration and make field applications more systematic.
Development of current condition assessment and target definition model for water balance practices in sustainable water loss management
(Iwa Publishing, 2022) Bozkurt, Cansu; Firat, Mahmut; Yilmaz, Salih; Ates, Abdullah
In water distribution systems, water losses should be defined accurately and systematically. The water balance method is one of the most basic analyzes applied in water loss management. In this study, a new method was proposed to evaluate the data quality of water balance components and application levels of the water balance practices by considering a total of 27 components. The developed model was applied in 4 pilot water administrations. The weaknesses and strengths in water balance practices were determined by considering the scoring in accordance with the dynamic structure of each administration. The quality of basic data measurement components and application levels of water balance practices are at good level in Administrations II and IV, at poor level in Administration I, and at average level in Administration III. Moreover, quality of water balance analysis and performance monitoring practices are at good level in Administrations II and IV, at poor level in Administrations I and II. Thus the components that need improvement in each administration were identified and improvement process was suggested. It is thought that this model will make a significant contribution to the testing of current application levels of water loss management components for practitioners and decision makers.

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