District Metered Areas Research Articles

A framework for real-time disinfection plan assembling for a contamination event in water distribution systems

Water distribution system contamination events caused by intentional, negligent, or accidental intrusion of biological, chemical, or radioactive contaminants have significant impacts on the health of the populations that it services. Therefore, it is important to have an effective plan that can be readily implemented to minimize the impact of these contamination events. However, limited research has been focused on strategic planning of the decontamination process of the contaminated infrastructure. This paper proposed a framework for assembling a disinfection plan in real-time by (1) partitioning a WDS into a number of district metered areas (DMAs), (2) generating a solution region for each of the DMAs, and (3) assemble an effective decontamination plan using solution region generated. This framework has been applied to three contamination events. The results show that, when planning for the decontamination stage of a contamination event, the use of the proposed framework can (1) significantly reduce the response time, (2) improve the quality of the decontamination plan, and (3) provide a model for optimizing the resource allocation.

Mitigasi Non Revenue Water (NRW) Sistem Jaringan Distribusi pada District Meter Area (DMA) Zona Kota Blahbatuh PDAM Gianyar

The most common problem with drinking water supply is Non Revenue Water (NRW). NRW can be grouped into two types, namely physical water loss and non-physical water loss. This study aims to determine the NRW size, NRW causes, counter measures that can be done to suppress NRW. The results of evaluation of distribution networks that occur in the Blahbatuh City Zone District Meter Area (DMA) PDAM Gianyar. The difference between the amount of water distributed and the amount of water recorded in the account is NRW. The way to find out the cause and control of NRW is to analyze the results of the step test, UFM test (Ultrasonic Flow Meter), and conduct the interviews with employees of PDAM. The evaluation of distribution networks is only done in DMA Pande that has completed data. The amount of NRW that occured in the Blahbatuh City Zone is 474,142.83 m3/year (59.91%). The water loss is caused by damage to pipe accessories, leaky pipes, inaccuracies in the accuracy of the water meter. The water loss can be overcame by establishing a DMA, replacing pipe accessories, calibrating and replacing water meters. The evaluation results for the existing conditions of the distribution network in DMA Pande of Blahbatuh City Zone have not worked optimally. It seen from the results of the waternet and from the number of SR’s that have not met the requirements for the formation of a DMA.

Automatic Multiscale Approach for Water Networks Partitioning into Dynamic District Metered Areas

Water distribution systems (WDSs) today are expected to continuously provide clean water while meeting users demand, and pressure requirements. To accomplish these targets is not an easy task due to extreme weather events, operative accidents and intentional attacks; as well as the progressive deterioration of the WDS assets. Therefore, water utilities should be ready to deal with a range of disruption scenarios such as abrupt variations on the water demand e.g. caused by pipe bursts or topological changes in the water network. This paper presents a novel methodology to automatically split a WDS into self-adapting district metered areas (DMAs) of different size in response to such scenarios. Complex Networks Theory is proposed for creating novel multiscale network layouts for a WDS. This makes it possible to automatically define the dynamic partitioning of WDSs to support further DMA aggregation / disaggregation operations. A real, already partitioned, water utility network shows the usefulness of an adaptive partitioning when the network is affected by an abnormal increase of the peak demand of up to 15%. The dynamic DMA reuses the assets of the static partitioning and, in this case, up to the 82% of resilience is restored using 94% of the assets already installed. The results also show that the overall computational and economic management costs are reduced compared to the static DMA partition while the hydraulic performance of the WDS is simultaneously preserved.

Machine-Learning–Based Risk Assessment Method for Leak Detection and Geolocation in a Water Distribution System

AbstractCurrent leak detection practice in a water distribution system consists of monitoring the distributed volume in a district metering area (DMA) and the consumption measured with automated me...

Uniformity and Heuristics-Based DeNSE Method for Sectorization of Water Distribution Networks

Sectorization of a water distribution network (WDN) into district metered areas (DMAs) is a proven solution for proactive leakage control. Traditionally, WDN sectorization is conducted by local experts using a trial-and-error approach, often resulting in the identification of arbitrary solutions. Some recently published methods try to improve WDN sectorization by automating the process, especially by using optimization. Various sectorization criteria, constraints, and limitations are introduced, which often fail to consider the issues faced by poorly managed WDNs such as limited funds and shortage of water balance data. These methods also have poor computational efficiency imposed by optimization methods used. This paper presents a new distribution network sectorization method (DeNSE), that overcomes these deficiencies. This method is based on a heuristic procedure in which WDN sectorization is driven by efficient tracking of water balance data and determining the lowest cost investment needed to maintain the same level of operational performance. The above-mentioned set of criteria is particularly well suited for initial sectorization of WDNs when major uncertainties in water balance data often lead to poor management decisions. The DeNSE method is validated and benchmarked against other sectorization methodologies in a case study of a large, real-world WDN. The results show that DeNSE can identify sound, realistic sectorization solutions that are in some respects better than corresponding solutions reported in the literature. DeNSE also enables high computational efficiency, ensuring its applicability to real-world WDNs.

Leak Localization in Water Distribution Networks Using Pressure and Data-Driven Classifier Approach

Leaks in water distribution networks (WDNs) are one of the main reasons for water loss during fluid transportation. Considering the worldwide problem of water scarcity, added to the challenges that a growing population brings, minimizing water losses through leak detection and localization, timely and efficiently using advanced techniques is an urgent humanitarian need. There are numerous methods being used to localize water leaks in WDNs through constructing hydraulic models or analyzing flow/pressure deviations between the observed data and the estimated values. However, from the application perspective, it is very practical to implement an approach which does not rely too much on measurements and complex models with reasonable computation demand. Under this context, this paper presents a novel method for leak localization which uses a data-driven approach based on limit pressure measurements in WDNs with two stages included: (1) Two different machine learning classifiers based on linear discriminant analysis (LDA) and neural networks (NNET) are developed to determine the probabilities of each node having a leak inside a WDN; (2) Bayesian temporal reasoning is applied afterwards to rescale the probabilities of each possible leak location at each time step after a leak is detected, with the aim of improving the localization accuracy. As an initial illustration, the hypothetical benchmark Hanoi district metered area (DMA) is used as the case study to test the performance of the proposed approach. Using the fitting accuracy and average topological distance (ATD) as performance indicators, the preliminary results reaches more than 80% accuracy in the best cases.

The Analysis of Water Supply Operating Conditions Systems by Means of Empirical Exponents

The stochastic character of water consumption by consumers and the technical condition of water supply systems are the main deterministic random factors influencing the observed changes in flow rate and pressure. The implementation of Supervisory Control and Data Acquisition (SCADA) systems resulted in the creation of dispersed data sets coming from the devices controlling the operation of the water supply system. Thanks to the use of metadata and advanced computer systems of analysis, data from various sources can be analyzed to detect the operating conditions of the water supply system. The aim of the research was to analyze an empirical exponent, determined on the basis of flow rate and pressure measurements for one of the District Metered Areas (DMAs). Modern supervised and unsupervised machine learning systems were implemented to classify the obtained results. The results of the research showed that on the basis of the established empirical exponent in the systems in which the pressure is reduced at night, it is possible to qualify the operating conditions of the water supply system in the DMA with accuracy of up to 90%. The conducted tests may be implemented as a component of expert diagnostic systems in water companies.

Sectorización basada en la teoría de los grafos de redes de distribución de agua potable con una y con múltiples fuentes

A graph theory based methodology for design of water network partitioning is proposed. Both multiple and single source networks are considered. In the first case the partition refers to the definition of isolated sectors, each of them supplied by its own sources. The shortest paths from each water source to each network node are found and each network node is assigned to be supplied exclusively by the source with the shortest path distance to it. The pipes to be closed are the edge separators of such partition. In the second case the partitioning problem refers to a division of the network in relatively small district metering areas (DMAs) each of them fed by a single pipe. A hierarchical tree for the graph is constructed using a breadth-first search. A recursive approach is applied on this tree to find the design flow rates in each pipe summing the demand of descendant nodes. Based on these flow rates the nodes belonging to each DMA are found. The pipes to be closed are defined as the chords between branches of the hierarchical tree lying below the feeding pipe. The procedure has been tested on a real medium city all-pipe water distribution network model.

Burst Detection by Analyzing Shape Similarity of Time Series Subsequences in District Metering Areas

AbstractThe paper proposes a burst detection method that relies on shape similarity analysis of time series subsequences (i.e., slices of time series). Subsequence libraries are constructed using f...

Water Distribution Network Reliability Assessment and Isolation Valve System

Mechanical reliability analysis of water distribution networks (WDNs) refers to the assessment to provide correct service to customers under abnormal functioning conditions due to system component failures. Mechanical reliability depends on the isolation valve system (IVS) effectiveness in isolating a network segment and on the failure probability. The main aim of this work was the formal development of reliability indicators considering pressure-driven analysis (PDA) for customer demand and topological changes. Three factors influencing reliability were identified: (1) the hydraulic behavior of the still-connected network; (2) the topological performance of the IVS; and (3) the topological performance of the IVS with respect to unintended isolation. The reliability performance assessment of the network over time depends on the hydraulic capacity of the WDN under abnormal functioning conditions and on two IVS performance topological indicators of the risk of disconnection and unintended isolations. The hydraulic capacity was computed using PDA, whereas the topological risks were computed considering the unsupplied demand in the isolated segment and the normalized failure probability, i.e., the probability of a segment disconnection for an assumed failure occurrence in the network. The development of a modularity index for an IVS was achieved in a consistent framework and the integrated design of an IVS and district metering areas was introduced. The framework allows the analysis of the isolation valve failure. A real Apulian WDN was used to discuss and demonstrate the theoretical findings.

Optimal selection of number and location of pressure sensors in water distribution systems using geostatistical tools coupled with genetic algorithm

Abstract This paper presents a novel methodology for designing an optimal pressure sensor to make average pressure field in water distribution systems (WDS) more accurate via geostatistical tools coupled with genetic algorithm (GA) under normal operating condition. In light of this, the objective function is introduced based on geostatistical technique as variance of residual of block ordinary kriging (BOK). In order to solve the problem of sensor placement, three different approaches, so-called, simplified, exhaustive, and random search optimization are considered. To the best of the authors' knowledge, this is the first time whereby geostatistical tools are used to design a pressure monitoring network in the WDS. The proposed methodology is first tested and verified on a literature case study of Anytown WDS and then is applied to a real-world case study referred to as C-Town consisting of five district metered areas (DMAs). The proposed methodology has several advantages over existing more conventional approaches which will be demonstrated in this paper. The results indicate that this method outperforms the conventional paradigms in current use in terms of mathematical labor and the results are quite promising.

A hybrid hydraulic model for gradual transition from intermittent to continuous water supply in Amman, Jordan: a theoretical study

Abstract Intermittent water supply (IWS) is associated with numerous negative consequences with respect to health and access along with technical impacts that aggravate the sustainable supply of water, thus rendering Sustainable Development Goal 6.1 (SDG 6.1) hardly achievable. The gradual, or zone-by-zone, transition from IWS to continuous water supply is very effective in terms of economic scarcity. This work focused on designing a theoretical ‘hybrid’ hydraulic model where both types of services, intermittent and continuous, were included in the modelling. The preliminary, not calibrated model, which was applied in a district in Amman, has shown to be efficient on both the technical and economic sides as it achieves independent district metering areas. Sustainable access to water, however, necessitates an integrated solution taking into account the technical, economic, social and psychological factors along with the modelling aspect highlighted in this work.

Multiobjective Optimization of Control Valve Installation and DMA Creation for Reducing Leakage in Water Distribution Networks

AbstractThis paper presents a novel methodology for optimizing simultaneously the installation of control valves and the creation of district metered areas (DMAs) in water distribution networks (WD...

Real benefits of leak repair and increasing the number of inlets to energy

Abstract Two real cases of energy audit were investigated in a district metered area (DMA) of the Metropolitan Waterworks Authority in Bangkok, Thailand. The first case was energy audits before and after leaks were repaired. The repairs resulted in a 9% reduction of inflow to the DMA. We estimated that the input energy to the DMA reduced 8% while the energy in water delivered to customers increased 8%. Thus, two benefits of reducing leakage to energy were found. In the second case, we temporarily opened a boundary valve connecting to the trunk main to function as another inlet to the DMA, so the number of inlets increased to two. The new inlet was nearer to main distribution pipes that delivered water to more customers than the first one. Thus, the inflow from the old inlet decreased to only 10% of the total inflow. The estimated input energy increased slightly by 4% because the inflow and leakage did not reduce, but the energy delivered to customers increased greatly (16%) due to a significant decrease in friction loss. Thus, reducing leakage and selecting the right hydraulic locations of inlets can benefit energy efficiency in DMAs substantially.

Generalized Normalized Cut and Spanning Trees for Water Distribution Network Partitioning

AbstractThis study present an efficient graph-theoretical method for automatic design of district metered areas (DMAs) in water distribution networks (WDNs). The proposed method consists of two mai...

Reducing Impacts of Contamination in Water Distribution Networks: A Combined Strategy Based on Network Partitioning and Installation of Water Quality Sensors

This paper proposes a combined management strategy for monitoring water distribution networks (WDNs). This strategy is based on the application of water network partitioning (WNP) for the creation of district metered areas (DMAs) and on the installation of sensors for water quality monitoring. The proposed methodology was tested on a real WDN, showing that boundary pipes, at which flowmeters are installed to monitor flow, are good candidate locations for sensor installation, when considered along with few other nodes detected through topological criteria on the partitioned WDN. The option of considering only these potential locations, instead of all WDN nodes, inside a multi-objective optimization process, helps in reducing the search space of possible solutions and, ultimately, the computational burden. The solutions obtained with the optimization are effective in reducing affected population and detection time in contamination scenarios, and in increasing detection likelihood and redundancy of the monitoring system. Last but most importantly, these solutions offer benefits in terms of management and costs. In fact, installing a sensor alongside the flowmeter present between two adjacent DMAs yields managerial advantages associated with the closeness of the two devices. Furthermore, economic benefits due to the possibility of sharing some electronical components for data acquisition, saving, and transmission are derived.

Multiphase Procedure to Design District Metered Areas for Water Distribution Networks

AbstractDividing a water distribution network into subsystems can improve the efficiency and ease of achieving management goals. Subsystems or district metered areas (DMAs) are isolated control zon...

Decentralized infrastructure approach for successful water supply systems in India: use of multi-outlet tanks, shafts and manifolds

The design and operational practice of water supply schemes (WSSs) in India is discussed in the context of the prevailing performance of the systems. Issues such as the tremendous gap in design and operation, unskilled manpower, and unmanageably large operation zones are identified as the main causes of the failure of WSSs in India. The failure of large-scale infrastructure creation in meeting service requirements is also discussed. The optimum scale of operation is estimated based on the ideal design and prevailing population densities in India. This work proposes a decentralized infrastructure approach through the use of multi-outlet tanks, shafts and manifolds. Each of these components is described in detail, and the manner in which these will help improve the current operation of WSSs in India is documented. Specifically, multi-outlet tanks will help achieve a design that enables the establishment of district metering areas for water distribution, shafts will serve as hydraulic separators between subzones, and manifolds will achieve a controlled water supply at various stages of the WSSs. These simple low-cost components will help to achieve water supply operations with minimal need for human intervention and automation.

Water Quality Mapping of Piped Water Supply in Malang City - Indonesia

PDAM Tirta Dharma of Malang City is probably the only water supply company (PDAM) in Indonesia which distributes drinking water to its customers at city wide. The PDAM is easily entitled to distribute drinking water as the raw water is originated from springs and groundwater with high quality of raw water supply. Raw water is simply chlorinated prior to distribution which then water must have residual chlorine of at least 0.2 mg/L, no total coliform, and minimum pressure heads of 1 bar at any house connection of the customers. PDAM Malang has 85 district meter areas (DMA) which covers 85% of Malang City in 2018. This study is aimed to assess public water service in Malang City regarding residual chlorine, total coliform, and residual heads at selected house connections which the results are then plotted using open source software of ArcGIS 10.3. Out of 85 DMA, 58 areas were able to distribute drinking water in accordance with Indonesia Drinking Water Standard. Out of 85 selected sampling points for the three water services, 68% showed that the water quality complied with Indonesia Standard.

Optimizing the Formation of DMAs in a Water Distribution Network through Advanced Modelling

Water pressure management in a water distribution network (WDN) is a key component applied to achieve desirable water quality as well as a trouble-free operation of the network. This paper presents a hybrid, two-stage approach, to provide optimal separation of a WDN into District Metered Areas (DMAs), improving both water age and pressure. The first stage aims to divide the WDN into smaller areas via the Geometric Partitioning method, which is based on Recursive Coordinate Bisection (RCB). Subsequently, the Student’s t-mixture model (SMM) is applied to each area, providing an optimal placement of isolation valves and separating the network in DMAs. The model is evaluated on a realistic network generated through Watergems and is compared against one variation of it implemented, including the Gaussian Mixture Model (GMM) as well as the Genetic Algorithm (GA) approach, obtaining impressive performance. The implementation of both stages was deployed in a MATLAB environment through the Epanet toolkit. The proposed system is very promising, especially for large size WDNs due to the decreased running time and noteworthy reduction of pressure and water age.