Collective Water Supply System Research Articles

Safety of Tap Water in Terms of Changes in Physical, Chemical, and Biological Stability

Monitoring the quality of tap water in the distribution system and the ability to estimate the risk of losing its sanitary safety is an important aspect of managing the collective water supply system. During monitoring, the physical, chemical, and biological stability of water was assessed, which is the main determinant ensuring the appropriate quality of water for consumers. The physicochemical and microbiological quality of water was analyzed for two distribution systems (DSs), including the analysis of heavy metals (Zn, Fe, Mn, Cr, Ni, Cu, Cd, Pb). The tests carried out showed that in both distribution systems, the water supplied to consumers met the guidelines for water intended for human consumption. It can be considered that the risk of uncontrolled changes in water quality in DSs with an average water production of <10,000 m3/d and the length of water pipelines < 150 km is very low. The water introduced into the system differed in the place of water intake and water purification technology, which influenced the final water quality. In DS(II), higher values were recorded for hardness, conductivity, calcium, alkalinity, nitrates, and DOC. It was found that the content of heavy metals during water transport to the consumer increased in the case of DS(I) for Zn, Ni, Cu, Cd, and Pb, and in the case of DS(II) for Fe, Mn, Ni, Cu, Cd, and Pb. The observed differences resulted from the different quality of the intake water as well as from different materials used to build internal installations and their age and technical condition. The analyzed tap water was characterized by physical and chemical stability. However, the water did not meet the guidelines for water biostability due to the increased content of biogenic substances.

Interrelationships of construction aspects of groundwater catchment wells for human consumption and pollution by multiresidues of pesticides

Human consumption of groundwater in catchment wells whose construction aspects are neglected in rural areas has been a growing reality, caused mainly by the deficient existence of public policies that enable the collective water supply system in these locations. However, it is also in rural areas that the most intensive use of pesticide compounds is made, which, depending on their physicochemical characteristics and the specificities of the environment where they are applied and the form of application, can pollute different environmental compartments, including groundwater. Therefore, the objective of this study was to carry out a comparative analysis between the constructive aspects of Underground Water Tubular Wells (UWTW) for human consumption purposes in a rural area of a municipality in the Missões Region of the state of Rio Grande do South (RS). and, the possible interrelationships with the presence of multiple pesticide residues. The constructive assessment considered Technical Standard N° 12.212:2017 (ABNT, 2017) and the determination of 26 pesticide compounds in 5 UWTW in the rural area of a municipality in RS. The results obtained inferred construction irregularities in all wells in the study, with emphasis on the absence of: sanitary protection slab, well identification plate, above-ground walls, sidewalks and, fencing. The presence of atrazine residues was also identified in concentrations above the LQm of UWTW-1 (0,107 µg L-1), UWTW-2 (0,019 µg L-1), UWTW-3 (0,019 µg L-1), UWTW-4 (0,066 µg L-1) and UWTW-5 (0,059 µg L-1). Finally, considering that the Serra Geral aquifer is of the fissural confined type, it is inferred that possible interrelationships between construction irregularities and the presence of the pesticide compound in the public water supply from catchment wells in rural areas may occur.

Water intake efficiency analysis in risk management of water supply systems - a case study of Głubczyce collective water supply system, Poland

Water intake efficiency analysis in risk management of water supply systems - a case study of Głubczyce collective water supply system, Poland

The Use of a Fault Tree Analysis (FTA) in the Operator Reliability Assessment of the Critical Infrastructure on the Example of Water Supply System

Background: Specialist literature indicates a large share of the human factor among the causes of failure of technical systems at the level of 70 to 90%, which depends on the sector studied. The collective water supply system is an anthropotechnical system, i.e., it is a complex connection between man and the technical system resulting from the deliberate influence of man on the technical system. Methods: The work presents an assessment of operator reliability of a selected water treatment process based on the fault tree analysis (FTA). Elementary events are determined by the operator’s error probability. Results: A failure tree was prepared for the peak event of the filter station failure, resulting from an operator’s error during the filter washing procedure. The probability of a peak event occurring is 0.0580. Conclusions: The developed fault tree allows for the identification of elementary events leading to an emergency event. The operator fulfills its task of maintaining the continuity of water treatment.

A New Concept of Crisis Water Management in Urban Areas Based on the Risk Maps of Lack of Water Supply in Response to European Law

The paper presents issues related to ensuring the safety of water supply, based on the analysis and assessment of the risk of the lack of water supply to consumers using risk maps, in accordance with the current global trend recommended by guidelines and procedures, compliance with which should be a priority activity in the struggle against adverse events, related to the functioning of every collective water supply system (CWSS). The work contribution is the development of an original methodology of risk analysis and assessment for the needs of mapping the risk of a lack of water supply in the normal operation of the water supply network, as well as during a crisis. The presented methods take into account the quantitative aspect of the lack of water supply, with the possibility of extending the proposed solutions with a qualitative aspect. The article will contribute to the development of knowledge in the area of analysis and assessment of the risk of a water supply failure in PsDyW, and will determine new standards in its graphical presentation. It is a response to the World Health Organization (WHO) requirements of providing protection for the critical infrastructure and ensuring access to water for all citizens in the European Union.

Physicochemical, microbiological quality, and risk assessment of water consumed by a quilombola community in midwestern Brazil.

The quality of the water consumed by a given community is related to its quality of life. In this sense, this study aimed to evaluate, from the perspective of health risk, the physical, chemical, and microbiological quality of drinking water, in a quilombola community, and the qualitative aspects intrinsic to its use and storage. For this, water samples, collected at the exits of the collective water supply system and from eight cisterns that store rainwater, used for human consumption, were analyzed. The samples were subjected to physical, chemical, and microbiological analysis, including adenovirus (HAdV) and enterovirus (EV). The probability of an individual acquiring infection through water consumption was determined by quantitative microbiological risk analysis using HAdV and Escherichia coli (EC) as reference pathogens. The results showed that the water in the deep tubular well had 270.8 mg/L of total hardness, leading to the rejection of its consumption by ingestion. Alternativity, the people in the community consume rainwater stored in cisterns. For this type of water, the presence of heterotrophic bacteria was found in 75%, total coliform was present in 100%, and Enterococci were detected in 25%. Furthermore, EC was present in 25%, EV in 50%, and HAdV in 100% of the samples. The probability of annual infection with HAdV and EC was, in the worst situation, 100% and 1.3%, respectively. Regarding the qualitative and quantitative aspects, there was a significant positive correlation between the absence of EC and the withdrawal of water from the cistern using a pump and the opposite when the withdrawal was carried out using a bucket or hose. Based on the results found, it is important to carry out actions aimed at improving water quality and, consequently, the quality of life of people living in the study community.

Method for Assessment of Water Supply Diversification

The approaching prospect of obligatory implementation and pursuit of Water Safety Plans forces water companies to reflect on supplies in crisis situations that, for example, relate to the closure of a basic intake, or scarcity of water due to climates changes (droughts). Where supplies are diversified, there can be greater certainty as to the continuity of good quality supply, even in an emergency. As one of each country’s systems of critical infrastructure, the collective water supply system (CWSS) should be protected, with the diversification of supply treated as a basic tool to raise levels of security among consumers. This article, therefore, presents a method from the authors’ by which diversification may be assessed, including by reference to basic and key elements of the CWSS capable of affecting the continuity of water supply. Sample calculations using the proposed method are also presented here for selected Polish cities. In the event, as only one Polish CWSS can be assigned to the category representing excellent diversification, the suggestion is clearly that Poland’s systems must still progress with the diversification of water supply, in order to further reduce the risk of water shortages.

Bayesian Inference in the Analysis of the Failure Risk of the Water Supply Network

Abstract One of the basic subsystems of the collective water supply system is the water distribution subsystem which has a direct impact on the reliability and safety of water supply to consumers. Failures of water pipes may cause water losses (leaks), interruptions in the water supply to consumers and can be the cause of secondary water pollution in the water supply network. It was proposed to use Bayesian inference to locate failures on the water supply network and to determine a posteriori probability of water network failure. It was found that the conditional probability of distribution water supply network failure is definitely higher than the conditional probability of home connections failure. The research results should be used by the water supply company during the development of an operational strategy for the renovation and modernization of the water supply network.

Water Loss Analysis as an Element of Operation Management of Water Supply System

Abstract The aim of the study was an cause and effect analysis of water losses in the collective water supply system of the city located in south-eastern Poland. The exploitation data provided by the water supply company from 2012 - 2016 was used for the analysis. The study uses the recommendations of the IWA (International Water Association) for the water balance making and determination of water loss indicators. The values of water loss indicators were compared to international standards and the technical condition of the network was determined. In addition, failure rate analysis of the water supply network was performed based on the failure rate index λ. Based on the performed analysis, it was found that the water supply company should consider renovation or replacement of the main network pipelines to increase the safety level of water supply, reduce the amount of water losses and the company exploitation costs.

Seasonality analysis of water losses in a selected collective water supply system

The aim of the study is to analyse the seasonality of water losses from a collective water-supply system (CWSS) on the example of a provincial city located in south eastern Poland. The analysis was based on exploitation data obtained from the water-supply company for the period 2012–2016. For the analysis of seasonality a method based on average homogeneous sub-periods was used, with a relative seasonality index and the absolute levels of seasonal fluctuations being determined. Water losses from the analysed CWSS are also characterised using unit water-volume indicators within the water supply network. Over the research period, the volume of water produced and sold was found to decline, even as the number of inhabitants using the network increased. On the other hand, there is a growing demand for water used for own purposes by company, as related directly to their development. Water losses and values determined for the water-loss volume indicator both show a downward trend for the analysed CWSS. It is further observed that, in January, March and May, the loss of water is above average, while the volume of water lost in the other months is below average.

Analysis of selected aspects of collective water supply system operation in the selected municipality

The purpose of the work was to analyze the exploitation of the collective water supply system (CWSS), on the example of Czudec, Podkarpackie CWSS. The water balance was prepared. The system operation was simulated using the Epanet software. The obtained data was presented in graphical form of pressure distribution on the network during the minimum and maximum demand. Water age simulations were also prepared, that is, the period of water residence in water distribution subsystem.

Method of Water Consumers Safety Analysis and Assessment

The subject of the publication is to present the method of water consumers safety analysis and assessment to implement the so-called Water Safety Plans (WSP), recommended by the World Health Organization (WHO) in Poland. The paper presents the method of water consumers safety analysis and assessment, which is based on failure mode and effects analysis (FMEA). The failure mode and effects analysis is widely used to analyse the reliability and safety of products and processes in technical systems. The procedure in the FMEA is based on the identification of potential undesirable events, assessment of effects and determining the causes of these events, assessment of frequency, the possibility of detection, estimating validity of the actions and estimating how to prevent undesirable events, re-examining and assessment of these events. The developed method of water consumers safety analysis and assessment is a complement and extension of recommended for WSP matrix methods, which according to the author's opinion is not sufficient for a proper analysis of undesirable events that may happen in collective water supply system (CWSS). The use of the FMEA method will allow for better identification of existing hazards and to determine the cause–effect relationships between them. Reliable access to drinking water is one of the basic conditions for the development of civilization.

Sources Of Incidental Events In Collective Water Supply System

Abstract The publication presents the main types of incidental events in collective water supply system. The special attention was addressed to the incidental events associated with a decrease in water quality, posing a threat to the health and life of inhabitants. The security method against incidental contamination in the water source was described.

The Concept Of Fuzzy Modeling Of Safety In Collective Water Supply Systems Using Bayesian Network

Abstract The paper presents the use of fuzzy Bayesian network in safety modeling with regard to collective water supply system (CWSS). The theoretical basis of Bayesian networks and fuzzy modeling were presented. The paper presents failure events threatening the CWSS safety. The probability of the risk of lack of water supply to the city was designated. The model allows to determine the fuzzy probability of the risk at a given level.

New directions for the protection and evolution of water supply systems - smart water supply

Water supply system should have excellent protection in case of undesirable events occurrence. In the future protection of these systems will be ensured through the use of intelligent management of smart metering and the implementation of the second generation CPTED strategies, presenting a new perspective on critical infrastructure protection, taking into account any possible crime, terrorism, sabotage or disaster. The paper presents the problem of the effective protection of critical infrastructure and the attention was drawn to appropriate protection of critical components from attacks, disasters and other adverse events. On this background the protection principles for water supply systems were formulated, the purpose of which is to prepare the resources and the public for undesirable events causing a threat to both human health and infrastructure. In case of the possibility of managing the shut off of particular recipients, not only areas, the priority of importance of providing water should be established. The exclusion of households seems to be a solution with the smallest financial losses. However, the attention should be paid to the so-called sensitive customers, e.g. the disabled people, the elderly, families with small children, etc. For proper operation of municipal infrastructure specialized companies are responsible which, in addition to managing the systems, are also responsible for ensuring protection of sensitive elements connected or used by them. The most obvious example of urban critical infrastructure system is the collective water supply system.

Analysis And Assessment Of The Security Method Against Incidental Contamination In The Collective Water Supply System

Abstract The paper presents the main types of surface water incidental contaminations and the security method against incidental contamination in water sources. Analysis and assessment the collective water supply system (CWSS) protection against incidental contamination was conducted. Failure Mode and Effects Analysis (FMEA) was used. The FMEA method allow to use the product or process analysis, identification of weak points, and implementation the corrections and new solutions for eliminating the source of undesirable events. The developed methodology was shown in application case. It was found that the risk of water contamination in water-pipe network of the analyzed CWSS caused by water source incidental contamination is at controlled level.

Niepewność w analizie ryzyka związanego z funkcjonowaniem systemu zbiorowego zaopatrzenia w wodę

Niepewność w analizie ryzyka związanego z funkcjonowaniem systemu zbiorowego zaopatrzenia w wodę

Standards of Water Services Quality Levels with Regard to the Reliability of Water Supply to the Recipients / STANDARDY JAKOŚCI POZIOMU USŁUG WODOCIĄGOWYCH Z UWZGLĘDNIENIEM NIEZAWODNOŚCI DOSTAWY WODY DO ODBIORCÓW

Abstract During the period of the structural changes in the processes of the European integration and regionalisation, the issue of the water services quality standards, which is associated with the social, economic and demographic development of the country, becomes more and more important. A properly functioning collective water supply system (CWSS) should ensure a continuous water supply to the recipients, with a suitable quality and adequate quantity (required pressure), at a specific time. These parameters must be maintained at the required level, which in reality is not so simple. Also indicators used for assess water services reliability for recipients are proposed. These indicators clearly evaluates the consequences of failures and at the same time retains the simplicity of estimation, which allows for its widespread usage in risk management.

Matrix Analysis of Risk of Interruptions in Water Supply in Terms of Consumer Safety / MATRYCOWA ANALIZA RYZYKA PRZERW W DOSTAWIE WODY W ASPEKCIE BEZPIECZEŃSTWA KONSUMENTÓW WODY

Abstract With regard to drinking water consumers, safety is understood as a probability to avoid threat arising from the consumption of water inconsistent with quality standards or the lack of water. Accordance with the Regulation of the Minister of Health water is safe for human health, if it is free from pathogenic microorganisms and parasites in the amount constituting a potential threat to human health, any substances in quantities hazardous to health and has no aggressive corrosive properties. Water supply reliability means providing stable conditions allowing to meet current and future demand for water in sufficient quantity and with required quality, in convenient time for water consumers and also at a price acceptable by them. In this study consumer (individual) risk rK was defined as the sum of the first kind of risk rKI, associated with possibility of interruptions in water supply and the second kind of risk rKII associated with possibility of consumption of water inconsistent with quality standards. Three-parameter matrix of risk was proposed. For presented method was made an application example based on exploitation data of collective water supply system, which may help to increase safety of water consumers.