Drinking Water Supply Network Research Articles

Monitoring the spatial evolution of groundwater quality during its diversion in the drinking water supply network in arid areas, case of Bechar city (Algeria Sahara)

Climate change has clearly affected the desert city of Bechar, located in southern Algeria, and this miserable situation for the supply of drinking water prompted the authorities to provide capabilities and funds to bring groundwater located 250 km away and transfer it to the city of Bechar. The characterization of these underground waters presents a bicarbonate-magnesian facies according to the diagram of Schöeller and Berkaloff; the representation of the data on the triangular Piper diagram shows that Boussir ground water has the magnesium bicarbonate facies. The calculation of the quality index (GWQI) shows that all samples taken from the boreholes belong to the good quality category. The long distance of diversion of this underground water and the quality of the materials used in the project under a dry desert climate made us carry out the process of monitoring and tracking the quality of the water from the well until it reaches the consumer. The results revealed that all the levels of the physic-chemical parameters do not exceed the WHO portability standards, except that a variation of certain values was observed at the level of the storage tank, this variation due to the mode of filling and the mixing of water in tubular form, without eliminating the effect of water stagnation. If we technically know how to produce high-quality drinking water, we cannot always ensure a safe and sustainable water supply of the same quality in distribution networks and reservoirs; it is from this principle that our article is based in order to reinforce the monitoring role.

Detection of Pharmaceutically Active Compounds in Tap Water Samples by Direct Injection HPLC/MS-MS: A Danger Signal in Deficiency in Residue Management.

To date, there is an increased risk to public health and the environment due to the presence of pharmaceutically active compounds within drinking water supply and distribution networks. Owing to this, a direct injection-HPLC/MS-MS method was developed for the simultaneous determination of 16 active pharmaceutical compounds in tap water samples: amoxicillin, ampicillin, cephalexin, cefotaxime, cefuroxime, ciprofloxacin, clarithromycin, clindamycin, chloramphenicol, cyproterone, erythromycin, flutamide, spironolactone, sulfamethoxazole, tamoxifen, and trimethoprim. Limits of detection (LOD) ranged from 0.2 to 6.0µg/L while quantification limits (LOQ) from 0.3 to 20µg/L. Recovery percentages were between 70 and 125%. Total analysis time was short, with all compounds being resolved in less than 2.1min. Of the 22 tap water samples collected and analyzed, the highest concentrations corresponded to amoxicillin (147µg/L) and ciprofloxacin (44µg/L). The findings could set a precedent for establishing safe levels of these compounds and increasing standards for tap water quality in this region.

Detecting wire breaks in prestressed concrete pipes: an easy-to-install distributed fibre acoustic sensing approach

The escalating water stress resulting from drought conditions in certain global regions underscores the imperative to minimize water losses, particularly within drinking water supply networks. One way to achieve this is by improving pipe monitoring systems to allow the early detection of possible structural collapse of the pipes. One type of pipe widely used in water mains is the prestressed concrete pipe, whose main cause of structural failure is the breakage of prestressing wires. This research paper analyses the ability of an easy-to-install distributed acoustic sensing (DAS) monitoring system using fibre optics to identify and locate the acoustic signal produced by the wire breaks in prestressed concrete pipes to make early detection of possible structural failures. For this purpose, a large experimental pipeline stretch was built (approximately 1 m in diameter and 40 m long) where wire breaks were simulated. Several variables were studied: the origin of the signal (to distinguish wire breaks from events of a similar nature), the location of the event in the pipe, the presence of background noise, the internal water pressure, the length of the prestressed wire not subject to bonding with the concrete and the presence of water in the pipe. The results showed that the DAS system could detect almost all events. In addition, two of the multiple parameters measured in the signals, the zero-crossing rate and the short-time energy, made it possible to precisely determine the signal’s origin and the event’s location. Another parameter measured, the duration of the signal in this case, made it possible to differentiate whether the events had occurred when the pipe was empty or full of water. These and other results in this paper present a highly promising perspective on using this DAS system in water main monitoring.

Hydraulic and Water Quality Simulation in a Drinking Water Supply Network: A Case Study of the Ain Regada Network

Abstract To ensure the quantitative and qualitative safety of the drinking water supply to urban and rural areas, drinking water supply network managers are always concerned to improve the quality of the service provided to consumers and the continuity and quality of the water distributed. They are also concerned to ensure better management of all water supply systems. The development of computer software has made network modelling an essential part of the design and management of water supply systems. In this context, this study focuses on the operation of the Ain Regada water supply network. The simulation of the operation of the network in its current state is carried out using Epanet software.

Rehabilitation of the water supply network of Timişoara City from Timiş County in Romania

In such an urban centre like Timisoara (the largest one from the West of Romania), the problem of water treatment for drinking, respectively wastewater collection and treatment, have always been issues of strategic importance to the community. The policies of the European Union to support the financing of the member states in the field of environmental engineering and protection represented the basic pillar in the development of the water supply network also in this case. In light of the increasing and pressing need to efficiently manage scarce water resources, there has been renewed interest by water distribution network owners to develop and implement water management strategies and tools that would assist in the integrated and automated management of those networks. The modernizations made at the treatment plants can be summarized in a few basic ideas: the automatic control of processes, lower costs, and higher safety. The most commonly used rehabilitation techniques for reducing both types of water losses are pressure management and pipeline rehabilitation. In Timişoara City, this modernization, and the rehabilitation of the water supply network led to a significant reduction of the environmental pollution (water, soil, air), and to a better protection of human health. Investments in modern technologies for water treatment, which allow an automatic monitoring of the process, translate into more safety in exploitation, and, implicitly, a better-quality control. The main objectives pursued in this study aim at: improving the quality of drinking water supplied to the population, ensuring continuous supply of drinking water, compliance with the regulations in force, both Romanian and European, and ensuring the access for the majority of the population at this system. There were followed the rehabilitation systems for street drinking water supply networks, also those for street sewerage networks, with modern constructive solutions.

ANALYTICAL STUDY OF THE WATER QUALITY FOR THE DRINKING WATER NETWORKS IN BECHAR CITY

The study carried out involves an evaluation of the physico-chemical parameters of drinking water networks in Bechar city (Algeria). In this work we have characterized the quality of drinking water, investigated the main sources of water pollution and proposed solutions to this problem. Today, the water consumer in Bechar city enjoys an aftertaste in drinking water, despite its treatment upstream of the dam. The installation of the dam began in October in 968, the drinking water supply system of the town of Bechar was carried out between 1978 and 1980, and the dam was inaugurated in May 1981. This work was initiated to better understand the quality of drinking water. The quality of drinking water must be checked upstream (sources of water) until downstream (consumer), it can also be degraded during its storage and passage through the distribution of drinking water networks. Contamination can come from the network itself. The results found show that almost all of the parameters analyzed comply with both national and international drinking water regulations. To this end, we have concluded that the supply of drinking water to the city of Bechar is subject to several constraints such as the degradation of drinking water supply networks and the aging of reservoirs.

Optimisation of chlorinedisinfection in drinkingwater supply network

Abstract Chlorination is one of the most commonly used procedures for drinking waterdisinfection. The research aimed to soptimise the subsequent disinfection ofdrinking water with chlorine in the water supply network in the city Velenje,taking into account the applicable legislation. The gradual reduction of chlorinedosage was implemented with simultaneous monitoring of selected physico-chemical and microbiological parameters of drinking water. During the two-month period, 418 samples were taken at 22 previously defined differentsampling spots. Free chlorine values were reduced from the initial 0,18 mg/L tothe final 0,08 mg/L at the outlet, while values at some remote sampling sitesreached only 0,01 mg/L of free chlorine. Microbiological analyses of samplesshowed that the drinking water met the limit values in the regulations, despitethe low values of free chlorine. Based on the results, a modified chlorination ofdrinking water was introduced in the tested supply area, and the introduction ofa similar regime in other supply areas is being actively considered. In this way,we reduce the consumption of disinfectants and ensure the supply of qualityand healthy drinking water to consumers.

Chlorine degradation in continuous and intermittent drinking water supply networks

ABSTRACT Chlorine is a widely used disinfectant in developing countries due to its efficiency and affordability. Millions of people in these countries receive water intermittently through piped networks. However, very little is known about chlorine decay in intermittent networks. In this work, field chlorine decay measurements were carried out in adjoining continuous and intermittent networks. Hydraulic modelling was done to determine the water velocity in networks using EPANET. Overall chlorine decay rates were estimated using field measurements and showed a good first-order fit. Decay rates in continuous and intermittent networks were compared, considering the influence of pipe velocity, material and diameter. The average overall decay rate for ductile and cast-iron pipes in intermittent network (1.7 ) was 1.5 times higher than that in continuous network (1.1 ). These results indicate that intermittency has a long-term effect on the overall chlorine decay in supply networks and its implications are discussed in this study.

New software to analyze hydraulic incidents in Algeria

Fifteen percent of the total volume produced is lost, which has become a major problem for water resource management in Algeria. The number of high leakages reduces the performance of the drinking water supply network. The disturbance of the drinking water supply observed by the citizens resulted from several incidents occurring mainly on the axis of production or distribution (e.g., breakage, leakage, pollution, electrical problems, and drought). To manage these incidents and for water distribution monitoring in the high-level strategic plan, monitoring and control software was developed for the Algerian Water Company (ADE). This software is an essential tool that helps managers of water resources to monitor the water supply situation throughout the national territory to ameliorate water public services. This dynamic software has been in use since 2016.

PERENCANAAN SISTEM JARINGAN DISTRIBUSI SISTEM PENYEDIAAN AIR MINUM PEDESAAN (SPAMDES) DI DESA PEDAWA KECAMATAN BANJAR BULELENG

Water is a very important natural resource for mankind. Pedawa Village of Banjar Subdistrict located in the southern part of Buleleng Regency with an area of 16.68 km2 which has limited clean water services. Where the level of SPAMDES service which is only 29% or 1,672 people out of 5,733 people causes the fulfillment of clean water in Pedawa Village is still low, there are 4 springs used in SPAM Pedawa Village but not all communities get water, so it is necessary to plan an optimal rural drinking water supply network system (SPAMDES). The planning of this distribution network system is assisted by WaterNet where the software uses energy potential to see the extent to which water from the spring can flow through the distribution network.. The data required in this planning are elevation, discharge and coordinate point to calculate energy loss, pipe length and pump head and the number of residents of the last 6 years for projected population growth for 20 years. The results of projected water needs in the service area were obtained for Lambo Reservoir 54 m3, Lambo2 Reservoir 99 m3, Bangkiang Sidem1 Reservoir 45 m3, Bangkiang Sidem2 Reservoir 45 m3, Reservoir Gelunggang 75 m3, Asah Reservoir 15 m3, Insakan Reservoir 9 m3 and Munduk Waban Reservoir 1.5 m3. Based on the results of network simulations with galvanized pipes and flow systems with pumps and gravity obtained results for Constant and Extended flow types on WaterNet hydraulically the network can provide services as desired on each node. Where the pipe for the transmission network is obtained a pipe diameter of 10 and 5 cm, and for the distribution network obtained a pipe diameter of 15, 10 and 5 cm

Microplastics throughout a tap water supply network

AbstractThe aim of the present study was to evaluate the presence of microplastics in drinking water along a large distribution water supply network. Tap water was collected in situ at sampling cabinets using an in‐line sampling procedure that provided a representative sample with minimal risk of external contamination and avoided the transportation of large volumes to the laboratory. Microplastics > 50 μm were analysed via Fourier transform infrared spectroscopy (FTIR). Microplastics were detected in 38% of samples with a mean concentration of 0.01 microplastics per litre and polymers identified were polypropylene (PP), polyester (PES) and polyamide (PA). Detection of polytetrafluoroethylene (PTFE) and silicone particles were associated to the maintenance of cabinets. This study contributes to increase the knowledge regarding the presence and behaviour of microplastics throughout a large drinking water supply network providing water to 3 000 000 inhabitants. Results indicate that the pipes and the supply network not release microplastics into the drinking water.

PROBLEMS OF PARKS’ RENOVATION IN ZAPORIZHZHIA

The problem of renovation of urban spaces in the ratio of city-forming zones (industrial, rural and recreational) and «shuttle migration» for urbanized cities of Ukraine is substantiated on the example of renovation of unique objects of Zaporizhzhia city – factory parks. The development of park zones in connection with the development of the city is traced. A survey of a few parks revealed that in almost every park there are problems of engineering improvement. Inconspicuous irrigation and drinking water supply networks, as well as waste water systems, especially drainage, should be connected to park paths and areas for various purposes, as well as fully take into account the terrain. Power supply systems must also meet the specifics of the park. Amusement rides must be kept at safe distances from crowded places and properly insulated. Park lighting systems are not only utilitarian in nature to provide adequate lighting, but also design to have a modern stylish look. The analysis of perspective directions of development of park zones of Zaporizhzhia has shown that in the city the water area of the Dnipro river is weakly used for creation of artificial reservoirs, channels, bays. It is recommended to use this natural complex more widely in combination with artificial existing and new architectural objects. The architectural panorama of the shoreline of the Dnipro river within the central part of the city should be saturated with a compositional network of artificial lakes and straits, as well as sandy alluvial islands. The ways of solving the problems of renovation of urban spaces in the ratio of city-forming zones are determined. The complex architectural concept of connection of park and recreational zones, development of the central part of Zaporizhzhia city and the Khortytsia island is presented.

Drinking water quality assessment using Principal Component Analysis: Case study of the town of Souk Ahras, Algeria

Water quality can be considered a key contributor to both health and disease for humans. To obtain more advanced information about water quality the principal component analysis (PCA) was applied using the drinking water supply network data during four seasons in 2018 in Souk Ahras city/Algeria in order to extract principal factors that can explain the quality of drinking water. These factors aim to bring together the main explanatory elements of the water quality and their order of responsibility on the quality of the water through physicochemical parameters measured in situ. During the course of study 14 parameters were used for the characterization of the quality of drinking water in Souk Ahras city, these parameters were replaced by six (6) principal components explaining approximately 65.33% of the variance of the data. The study highlights two main problems, the strong signs of the presence of harmful germs and probably malfunction in part of the equipment of the processing and distribution facilities; and second, amount of the residual chlorine in water

Modeling and Optimization of the Drinking Water Supply Network—A System Case Study from the Czech Republic

In this study, we investigated the modelling and optimization of drinking water supply system reliability in the village of Zaben, Czech Republic. An in depth overview of the water supply network in the municipality, passport processing and accident and malfunction recording is provided based on data provided by the owner and operator of the water mains as well as the data collected by our own field survey. Using the data processed from accident and failure reports in addition to water main documentation, the water supply network in Zaben was evaluated according to the failure modes and effects analysis methods. Subsequently, individual water supply lines were classified based on their structural condition. In addition, a proposed plan for financing the reconstruction of the water supply mains in Zaben was created. As such, this study provides an overall assessment of the water supply network in Zaben alongside a proposed plan for the structural restoration of the water supply system, which accounts for the theoretical service life of the system and the financial resources of the owner.

Do membrane filtration systems in drinking water treatment plants release nano/microplastics?

Drinking water treatment plants (DWTPs) are thought to be able to remove many micropollutants including nanoplastics (NPs) and microplastics (MPs). However, few studies have focused on the water treatment process itself producing NPs and/or MPs. This paper discussed the possibility of releasing NPs and MPs from organic membranes in drinking water treatment plants. The effects of physical cleaning, chemical agents, mechanical stress, aging, and wear on the possibility of membrane breach during long-term use were analyzed. Further analysis based on membrane aging mechanisms and material properties revealed that the membrane filtration systems could release NPs/MPs to drinking water supply networks. Although the toxicity of membrane materials to human body needs further study, the action that should be taken to treat the release of NPs/MPs in DWTPs cannot be ignored: (1) in-depth study of the generation and release mechanisms of NPs/MPs; (2) reconsideration of membrane life cycle design; (3) determination of NPs/MPs concentration limits in drinking water through toxicity assessment; (4) accelerating development of biomembrane and inorganic membrane materials; and (5) unification of NPs/MPs sampling and testing standard. Accordingly, more research needs to be conducted to investigate the release of NPs and/or MPs from DWTPs.

Kinetic modeling of trihalomethane evolution from UV 254 nm absorbance after chlorination on a drinking water supply network

La formation des trihalométhanes (THM) est associée à la réaction du chlore avec la matière organique résiduelle contenue dans les eaux traitées avant distribution. Elle se poursuit dans le temps sur le réseau de distribution jusqu’au robinet du consommateur. Le respect de la norme des 100 μg/L sur les points les plus éloignés peut être critique sur des unités de production où la matière organique résiduelle en fin de traitement peut se montrer très réactive, en lien à sa composition et à des facteurs aggravants comme la température, le temps de séjour hydraulique et la présence de bromures. Dans ce contexte et en visant en priorité les eaux superficielles à pollution moyenne à forte en matière organique, la R&D Saur a développé un modèle prédictif de formation des THM en basant la construction sur trois objectifs principaux : une quantification en unité de masse de THM totaux, la prévision la plus juste sur les fins de réseau pour des temps de séjour dépassant les 72 h et, enfin, que le modèle puisse être employé sur les installations industrielles comme outil de diagnostic et d’aide aux réglages d’exploitation des traitements unitaires. Le modèle a été bâti à partir d’essais de laboratoire menés sur des eaux traitées de deux unités de production avant chloration. Les protocoles mis en oeuvre ont permis de développer une modélisation à partir de l’absorbance UV à 254 nm. L’équation cinétique de production permet d’évaluer précisément les concentrations en THM totaux à moyen et long termes sur une gamme étendue de températures : 7 à 25°C. Le modèle intègre le « bromide incorporation factor », indice de caractérisation de l’état bromé, qui permet d’exprimer les résultats en unité de masse de THM totaux. L’applicabilité du modèle à d’autres groupes d’eaux est également présentée.

Rapid Lab Grown Biofilm As a Tool for Engineering Sensor Networks of Biofouling-Resistant Electrochemical Sensors

Robust and rapid biofilm formation is not only a major interest in the development of microbial fuel cell, but it is also be of relevance to the development of indwelling environmental sensor networks. Sensor networks offer real-time, online and long-term monitoring which is an attractive monitoring strategy for water industry to prepare for increasing demand for clean water due to increased urbanisation and the pressures of climate change. Sensor networks support the development of robust and managed drinking water supply networks that are essential to human health. Fouling of sensors due to biofilm formation is very common in indwelling situations and it is a major drawback in the development of sensor networks. Sensors will fail once it is fouled and it can happen in just a couple days or weeks. Engineering robust sensor networks begins with designing a biofouling resistant sensors. Electrochemical sensors are inexpensive and simple to construct and operate, and it is widely used in water industry. Understanding how biofilms affect electrochemical sensor performance is important to enable detection of malfunction in situ, and can inform the development of methodology to restore the performance in situ. Networks can consist of hundreds of sensors and automated restoration of function in biofouled sensors is thus essential. Lab-based models play a vital role. However, it is not always possible to recreate the real conditions for biofilm formation in the lab and it can take too long for it to form. In a situation in which it is not possible to build a permanent testing setup, rapid lab grown biofilm is desirable. Adhesion of pioneering bacterial cells to the surface is the most crucial step in biofilm formation. Adhesion of cells to surfaces can be accelerated by altering the surface chemistry of the surfaces. One way to do this is by plasma treatment of the surface. Formation of a lawn of biofilm is desirable to model early biofouling event. Polysaccharide production that forms the extrapolymeric substance (EPS) of biofilm can be induced by common biocidal substance such as triclosan. Electrochemically generated local concentration of hydrogen peroxide has similar consequences. In this work, we show that it is possible to form some coverage of biofilm on electrode surface in just two hours, which represents early biofouling event. It has a potential for the development of rapid lab grown biofilm that can be useful in developing fail-proof sensor networks.

Stabilization of uncertain nonlinear discrete-time switched systems with state delays: A constrained robust model predictive control approach

This paper studies the problem of robust stabilization for a class of nonlinear discrete-time switched systems with polytopic uncertainties and unknown state delay. Moreover, the control signal is assumed to be constrained. The objective of the proposed controller is to stabilize the switched system under arbitrary switching signals based on the switched Lyapunov function approach. Therefore, based on the constrained robust model predictive control method and an appropriate Lyapunov–Krasovskii functional, the sufficient conditions to guarantee the asymptotical stability of the switched system are developed as linear matrix inequalities. Through online solving an optimization problem, the predictive state-feedback controller is designed. Furthermore, in this delay-dependent approach, only the upper bound of time-delay should be known. Appropriate transient response, ability to handle constraints, and nonconstrained switching signal are the other advantages of the proposed method. Finally, the performance of the proposed approach is compared with a similar approach through a numerical example. As well as, to show the applicability of the proposed controller, it is applied to a drinking water supply network, as an application example.

EFFECT OF ROOF TANKS FILLING ON THE HYDRAULIC PERFORMANCE OF WATER SUPPLY PIPES NETWORK

Assiut city suffers from lack of available lands to build houses. The price of an apartment in Assuit city is considered the highest price in Egypt. So, people are forced to replace the old houses with 11 floors ones. This situation makes the city infrastructure under pressure and challenges. One of these challenges is the drinking water supply network, which is designed to lift water only to the third floor. In this situation, to feed the floors above the third floor with water, roof tanks are built above towers and are supplied with water from the main network through private pumps. These pumps fill the tanks through a short period and operate for limited times at a day. The water supply network is not designed for such type of operation. In this research, the effect of existing roof tanks on the flow behavior in the water supply pipes network is studied. Different Scenarios are considered for roof tanks filling through changing the period and time of filling. The actual pipes network is planned to serve new area and all the building in this area have 11 floors towers. For each scenario, pressure head, velocity and water age at different nodes and pipes in the network are predicted through extended period simulation.

Structural reliability of elevated water reservoirs under wind loading

In the field of civil engineering, concrete water storage tanks are considered as hydraulic structures occupying a special place among other structures. The location of these tanks is based on hydraulic considerations related to the desired service pressure for subscribers whose solution is obtained by a compromise with the topographical constraints. In southern Algeria and the highlands; in order to ensure adequate pressure in the drinking water supply networks, the tanks are then elevated to high heights, which puts them under significant stress during windstorms and sandstorms conditions that are frequent in the South Algerian. As the severe weather conditions due to high winds are common, the elevated water storage tanks are designed to withstand to winds speeds included between 25 and 31 m/s according to the Algerian Wind Code. Given the uncertain and randomness of this phenomenon, the classical deterministic calculations of the engineer become limited since they do not integrate the notion of failure probability of the structure. In this study, a probabilistic approach based on Monte Carlo simulations is used to analyze the reliability of elevated water tanks submitted to hazard storm of wind loading. The limit state functions are related to the ultimate and serviceability limit states of the concrete elevated tank under wind analysis. This reliability approach, takes into account mainly two parameters which are the wind speed and the concrete compressive strength considered as random variable. Fragility curves depending on wind zones are obtained, where they demonstrate the dominant failure modes that can cause the structural failure.