Water Distribution Systems Analysis Research Articles

A Simplified Methodology for Optimal Location and Setting of Valves to Improve Equity in Intermittent Water Distribution Systems

In this paper, a simplified methodology to increase the water distribution equity in existing intermittent water distribution systems (WDSs) is presented. The methodology assumes to install valves in the water distribution network with the objective to re-arrange the flow circulation, thus allowing an improved water distribution among the network users. Valve installation in the WDS is based on the use of algorithms of sequential addition (SA). Two optimization schemes based on SA were developed and tested. The first one allows identifying locations of gate valves in order to maximize the global distribution equity of the network, irrespectively of the local impact of the valves on the supply level of the single nodes. Conversely, the second scheme aims to maximize the global equity of the network by optimizing both location and setting (opening degree) of control valves, to include the impact of the new flow circulation on the supply level of each node. The two optimization schemes were applied to a case study network subject to water shortage conditions. The software EPA Storm Water Management Model (SWMM) was used for the simulations in the wake of previous successful applications for the analysis of intermittent water distribution systems. Results of the application of the SA algorithms were also compared with those from the literature and obtained by the use of the multi-objective Non-Dominated Sorted Genetic Algorithm II (NSGA II). The results show the high performance of SA algorithms in identifying optimal position and settings of the valves in the WDS. The comparison pointed out that SA algorithms are able to perform similarly to NSGA II and, at the same time, to reduce significantly the computational effort associated to the optimization process.

Qualification of Hydraulic Analysis Models for Optimal Design of Water Distribution Systems

The hydraulic analysis of water distribution systems (WDSs) is divided into two approaches, namely, a demand-driven analysis (DDA) and a pressure-driven analysis (PDA). In DDA, the basic assumption is that the nodal demand is fully supplied irrespective of the nodal pressure, which is mainly suitable for normal operating conditions. However, in abnormal conditions, such as pipe failures or unexpected increases in demand, the DDA approach may cause unrealistic results, such as negative pressure. However, despite these realistic hydraulic analysis approaches for WDSs being emphasized in the design process, this consideration was lacking in the design aspect. Therefore, in this study, the designs by the DDA-based design model and PDA-based design model are compared, and their design characteristics are analyzed to identify the efficiency of the WDSs design under abnormal system conditions. The developed PDA model was applied to three networks (a well-known benchmark system and a real-life WDN), and the results showed that the proposed model is superior to other reported models when dealing with negative pressure under abnormal conditions. In addition, the optimal design of WDN considered PDA is presented, and the optimal construction cost is decreased to increase the percentage of PDA.

Analisis Sistem Distribusi Air Bersih di Perumahan Ciomas Permai Kabupaten Bogor Jawa Barat

Water distribution systems are often problematic in terms of quantity, pressure, continuity and quality. The research aimed to analyze water distribution system of PDAM Tirta Kahuripan Kabupaten Bogor in Ciomas Permai Residence. The research was conducted by collecting primary and secondary data. Analysis of clean water distribution system was carried out using the EPANET 2.0. Ciomas Permai Residence was located in zone 6 of PDAM Tirta Kahuripan servive areas. The result showed that the quality of the distributed water was in accordance with the applicable standard and continuous for 24 hours even though there were significant discharge differences during peak hours. Based on the measurement on Sunday and Monday, the minimum discharge were 14.4 l/sec and 13.8 l/sec respectively, higher than customer requirements of 7.34 l/sec, The water distribution pressure ranged from 0.7 - 1.35 bar. The result of clean water distribution simulation using EPANET 2.0 showed that the velocity of water and headloss were not accordance with the applicable standards.

Failure assessment for drinking water distribution system in the case of Bahir Dar institute of technology, Ethiopia

In this paper, the issue of failure assessment in the drinking water distribution system was presented. This specific study was conducted on the water distribution system on the campus of Bahir Dar Institute of Technology. The current problem in Bahir Dar institute of technology is that the water infrastructure is aging and has not been spending adequate to repair, replace, or rehabilitate drinking water distribution systems. This develops higher stresses on the water distribution network causing pipes to crack, or rupture permanently while in service. Due to this problem, the whole water supply components in the distribution network led to increased water loss and quality reduction. The general objective of this study is to assess the risk of the water distribution system in the Bahir Dar Institute of technology water supply distribution system. In this study, a structural risk assessment was developed by using ARC GIS 10.5 and Water Cad V8i to get prioritize maps of the water distribution system and hydraulic analysis of the drinking water distribution system of the institute. In developing this assessment, the score was established based on the preset criteria to evaluate customer point risk and structural point risks such as water quality, water availability, pressure head adequacy, the flow rate of water, pipe, storage facility, and pump. Based on the result obtained from an equal weight approach, the score of the drinking water distribution system risk index is a medium level (2.56) with a low level of structural risk (2.5) and a medium level of consumer point risk (2.62). The results evaluated by the AHP method, structural risk has had the highest weight score (76%) which means it needs more priority than consumption point risk (24%), and the result of drinking water distribution system risk index laid at the medium level (2.7), it indicates the institution drinking water distribution system put at the satisfactory condition with the sum up the effect of medium structural risk index (2.65) and medium consumption point risk (2.82). Based on the findings and conclusions of the study, the components of the campus water supply distribution system, particularly parts of the pipe and the majority of the pump, should be replaced before they become obsolete, and suitable preventive measures should be taken.

Modular interdependency analysis for water distribution systems

Complexity in water distribution systems (WDSs) poses a challenge for analysis and management of the systems. To reduce the complexity, the recent development of complex network science provides a system decomposition technique that converts a complex WDS with a large number of components into a simple system with a set of interconnected modules. Each module is a subsystem with stronger internal connections than external connections. Thus far, the topological features of the modular structure in WDS have been extensively studied but not the behavioural features, e.g. the hydraulic interdependencies among modules. Therefore, this paper aims to quantitatively measure and graphically visualize the module interdependency in WDSs, which helps understanding the behavioural complexity of WDSs and thus various WDS analyses, such as pipe maintenance, model calibration, rehabilitation, and District Metered Areas planning. Specifically, this study first identifies the WDS's modular structure then measures how changes in the state of one module (i.e. any single pipe failure or perturbed demand within each module) affect the state of another module. Modular interdependencies are summarized in an interdependency matrix and visualized by the digraph. Four real-world systems are analysed, and three of them shows low interdependencies among most of the modules and there are only a few critical modules whose status changes will substantially affect a number of other modules. Hence, highly interconnected topologies may not result in strong and complex module interdependency, which is a fact that simplifies several WDS analysis for practical applications as discussed in this paper.

Towards resilient water supply in centralized control and decentralized execution mode

AbstractThis paper shares a vision that sustainable water supply requires resilient water infrastructures which are presumably in the centralized control and decentralized execution (CCDE) mode with multiscale resilience. The CCDE should be planned based on the multiscale structure of water infrastructures, in which the systems are divided into a number of hierarchically organized subsystems. The CCDE allows independent execution of all subsystems under normal situations yet coordination of subsystems at different scales to mitigate any disturbances during failure events, i.e. the multiscale resilience. This vision is discussed in detail for water distribution systems (WDSs). Specifically, the conceptual design of the multiscale CCDE is described, and progress on understanding the multiscale structures in WDSs is summarized based on the literature review. Furthermore, a few theories consistent with the multiscale CCDE concept are discussed which include the decomposition theorems, fractal theory, control theories, and complex network theory. The next step in the vision will be to identify the optimal multiscale structure for the CCDE based on the best trade-off of different goals of WDS analysis and management. This process needs support from not only innovative modelling tools and extensive datasets and theories but also inspiring exemplar systems, e.g. natural systems.

A Head Formulation for the Steady-State Analysis of Water Distribution Systems Using an Explicit and Exact Expression of the Colebrook–White Equation

Steady-state demand-driven water distribution system (WDS) solution is the bedrock for much research conducted in the field related to WDSs. WDSs are modeled using the Darcy–Weisbach equation with the Swamee–Jain equation. However, the Swamee–Jain equation approximates the Colebrook–White equation, errors of which are within 1% for ϵ/D∈[10−6,10−2] and Re∈[5000,108]. A formulation is presented for the solution of WDSs using the Colebrook–White equation. The correctness and efficacy of the head formulation have been demonstrated by applying it to six WDSs with the number of pipes ranges from 454 to 157,044 and the number of nodes ranges from 443 to 150,630. The addition of a physically and fundamentally more accurate WDS solution method can improve the quality of the results achieved in both academic research and industrial application, such as contamination source identification, water hammer analysis, WDS network calibration, sensor placement, and least-cost design and operation of WDSs.

Analysis of clean water distribution systems using EPANET 2.0 (Case study of Uma Sima Village, Sumbawa Regency)

The need for clean water is very important for humans because it is one of the benchmarks of successful development in an area. Where every area, especially Uma Sima Urban Village, Sumbawa Sub-district will experience an increase in population every year so that the need for clean water will increase. The purpose of this study is to determine the need for clean water and the distribution system of clean water pipelines in Uma Sima Urban Village for the next 20 years until 2037 by using the method of analyzing clean water needs with projected population numbers using the exponential regression formula and network simulations pipeline distribution with Epanet 2.0 software. Based on the results of the analysis carried out, it can be obtained the need for clean water at peak hours of 16.99 liters / second with a max day factor of 1.15 and 18,446 liters / second with a max of 1.25 days factor. Whereas for the distribution network simulation it was found that the distribution network is still effective for carrying water for the next 20 years, namely in 2037.

Analysis and Design of Continuous Water Distribution System against Existing Intermittent Distribution System for Selected Area in Pandharpur, M.S., INDIA

In infrastructural development the public drinking water distribution network which includes pipes, bents, valves, pumps, tanks etc. is one of the major investments. The design, modeling of distribution network with efficient outcome is an important task. Therefore, the present study is aimed at design of continuous as well as intermittent water distribution systems with adequate water pressure with the use of WaterGEMS Vi8 software. The study is carried out for Manisha Nagar and Padmavati in Pandharpur, Maharashtra. The system comprised of a pipeline network consisting of one source node and several demand nodes is considered to find its optimal geometrical layout which delivers known demands from source to consumers over a long period of time. The effect of forecasted resident population and floating population on demand, head loss gradient, pressure gradient is analyzed. This study is carried out for immediate stage - Year 2021, intermediate stage - Year 2036 and final stage - Year 2051. From the analysis it is observed that, as population increases from year 2021 to 2051, the demand, head loss gradient and pressure development increases.

Review on Optimisation of Water Distribution Network by Leakage Reduction

The ever-increasing demand for water and the limited resources available for the same pitches strongly for water conservation. Water Distribution Systems are found to have potential to conserve the water lost through them because of various operational and nonoperational reasons. There is an immediate need to manage water distribution system, by reducing leakages in them. This paper give insight about analysis of Water distribution system and estimation of leakages as a potential component of Non Revenue water in WDN. Further various techniques for leakage management are identified. Pressure management could be very efficient for minimizing the leakage in WDN.

Battle of Postdisaster Response and Restoration

The paper presents the results of the Battle of Postdisaster Response and Restoration (BPDRR) presented in a special session at the first International water distribution systems analysis & computing and control in the water industry (WDSA/CCWI) Joint Conference, held in Kingston, Ontario, Canada, in July 2018. The BPDRR problem focused on how to respond and restore water service after the occurrence of five earthquake scenarios that cause structural damage in a water distribution system. Participants were required to propose a prioritization schedule to fix the damages of each scenario while following restrictions on visibility/nonvisibility of damages. Each team/approach was evaluated against six performance criteria: (1) time without supply for hospital/firefighting, (2) rapidity of recovery, (3) resilience loss, (4) average time of no user service, (5) number of users without service for eight consecutive hours, and (6) water loss. Three main types of approaches were identified from the submissions: (1) general-purpose metaheuristic algorithms, (2) greedy algorithms, and (3) ranking-based prioritizations. All three approaches showed potential to solve the challenge efficiently. The results of the participants showed that for this network, the impact of a large-diameter pipe failure on the network is more significant than several smaller pipes failures. The location of isolation valves and the size of hydraulic segments influenced the resilience of the system during emergencies. On average, the interruptions to water supply (hospitals and firefighting) varied considerably among solutions and emergency scenarios, highlighting the importance of private water storage for emergencies. The effects of damages and repair work were more noticeable during the peak demand periods (morning and noontime) than during the low-flow periods; and tank storage helped to preserve functionality of the network in the first few hours after a simulated event.

Analysis and optimization of water distribution systems: A case study of Kurudu post service housing estate, Abuja, Nigeria

In a bid to impact the 6th goal of the 17 sustainable development goals, this study models and optimizes the water distribution systems (WDS) case study by using the water distribution system layout to estimate the water demand, model flow, velocity and head loss for the case study using EPANET software and finally optimizing the system using LINGO software. The optimization algorithm developed herein is characterized by seeking out the optimal least cost system parameters which ensures that the systems serve its purpose efficiently with hydraulic and heuristic rules and constraints normally used for pipeline design are satisfied and employed in the model in other to achieve the optimum solution. The model representation of the existing water distribution system was solved by using initial pipe diameters of 150, 200, 250, 300 and 400 mm size, the pressure generating elevation of 25, 30 and 35 m head characteristics. The problem evaluates seamlessly and the total run time was 0.23 s. Results showed that the optimum reservoir height is 25 m while the optimum pipe diameter was determined to be 300 mm and consequently a 38% reduction in total cost of installation, operation and maintenance of the Water distribution system (WDS).

Design and Analysis of Rural Water Supply System Using Loop 4.0 and Water Gems V8i for Nava Shihora Zone 1

The study presents the hydraulic design and analysis of Rural Water Distribution System (WDS) for Nava shihora region of zone 1 of the state of Gujarat, India. Water supply distribution system is designed for this study for population estimated for future 30 years. LOOP 4.0 and Water Gems v8i software have been used and the results are compared to determine the economical size of pipes for water distribution system. The economical size of pipes of water supply distribution system is designed by considering the constraints; residual pressure at each node, velocity of flow in pipe, head loos in pipes, material of pipes, elevated service reservoir level, peak factor and available commercial pipe diameters. Further water distribution system has been analyzed for extended period simulation (EPS) for the present population scenario for intermittent water supply using Water Gems v8i. Further water supply system is analyzed the residual chlorine concentration at nodes and in the pipe links and also the total cost of water supply system of rural region is estimated.

Seismic Functionality and Resilience Analysis of Water Distribution Systems

AbstractBuried water pipelines are subjected to corrosion deterioration and are vulnerable to extreme events (e.g., earthquakes). Corroded metallic buried pipelines have experienced severe damage d...

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

: 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.

Deficiency of Reliability Indicators in Water Distribution Networks

AbstractIn recent studies about reliability analysis of water distribution systems (WDSs), different reliability indicators have been used to measure and compare the reliability of water networks. ...

Battle of the Water Networks District Metered Areas

AbstractThe Battle of Water Networks District Metered Areas (BWNDMA) was the latest of the Battle of Water Networks competition series held at the 18th Water Distribution Systems Analysis Conferenc...

Analysis of water quality characteristic for water distribution systems

Abstract Since governments all over the world are paying more attention to water quality in water distribution systems (WDS), a method based on mass balance and first-order chlorine decay model was proposed to assess the efficiency of WDS involving water quality (represented by residual chlorine). The concepts of surplus chlorine factor (S) for nodes in individual pipes and comprehensive surplus chlorine factor (CS) for nodes in WDS were put forward to represent the water quality characteristic of nodes in WDS based on the assumption that the structure of the pipe network and quantity of chlorine dose are definite. The proposed method was applied to two examples of WDS and sensitivity analysis regarding chlorine decay coefficient (k0) was discussed. The results indicated that values of CS for nodes in WDS are affected by the inflow of nodes, which is determined by water demand and pipe length from water sources to nodes. In addition, the value of CS increases with k0 when the inflow of the node is larger than the optimized inflow. The results verified that the deduction of S for a single pipe can be generalized to WDS, and can measure the water quality characteristics for nodes in WDS easily.

Simulating Control Valves in Water Distribution Systems as Pipes of Variable Resistance

AbstractThis paper presents a simple valve simulation method integrable into the global gradient algorithm (GGA), which is widely used in hydraulic analysis of water distribution systems. In the pr...

Technical Analysis of Water Distribution System and Techno-economic Analysis of Distributed water: A Case Study of Rajkot City

Technical Analysis of Water Distribution System and Techno-economic Analysis of Distributed water: A Case Study of Rajkot City