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The primary objective of this work is to introduce a novel approach that modifies the method for analyzing and assessing the risk of water supply network failure. The approach aligns with recommendations from the World Health Organization and the European Union regarding the reliability and safety of water supply to consumers. The presented method for assessing the risk in the water distribution subsystem was based on the vulnerability identifying method (VIM) and involves the determination of the vulnerability index (VI). The VIM vulnerability factors considered encompass the failure rate, chemical stability of water, and issues related to water corrosion properties in water distribution subsystems. The obtained risk assessment includes parameters such as the probability of hazard occurrence, the consequences of these hazards, and vulnerability to them. This concept was evaluated using real operational data from the water distribution subsystem. The estimated risk level, under the given operating conditions, indicates its acceptability. [ABSTRACT FROM AUTHOR]

Turbidity impacts, not only on the aesthetic properties of water but also on many features capable of affecting health. This leaves the parameter in question as a very important indicator of the quality of surface water (due to a large amount of information on potential threats), and one capable of serving as a basis for risk analysis. Information on the turbidity of raw water was obtained from the water-supply company, with the focus being on data from the years 2010–2015. This reflects a research focus on the period following modernization of a treatment plant, completed in late 2009. Variation in the turbidity of raw water through the annual cycle was analyzed, with the finding that no cessation of delivery of water to the city on account of inadequate quality was necessitated. This further denotes a positive assessment regarding the efficiency of the water-treatment technology installed in 2009, which proved to be very effective at treating water whose turbidity changed rapidly from time to time, to reach several thousand NTUs. The paper also details attempts to determine the “a posteriori” probability of occurrence of turbidity of a certain value, in line with Bayesian theory. [ABSTRACT FROM AUTHOR]

The paper presents issues related to risks associated with the operation of small water supply systems on the background of water consumer safety assessment made on the basis of risk analysis. Definition of water consumer safety loss as a risk associated with the water consumption of poor quality or water lack was proposed. For this purpose, a three-parameter matrix is implemented with the parameters of the probability of a representative accident scenario, the losses of the water consumers and their protection. Risk management, together with the implementation of protective barriers of small water supply system against threats is a fundamental condition for the continued operation of the system. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present the novel approach to risk assessment in combination with failure and consequence analysis, depending on two parameters defined by the fuzzy functions: the repair time of water pipe and the cost of water pipe repair, what allow to determine particular risk levels. The presented methodology can be used to describe the functioning of the public water supply in terms of its renewal. [ABSTRACT FROM AUTHOR]

Within the frame of upgrading and modernisation of the Water Supply System (WSS), our work is focussing on the safety systems/devices implemented or that should be implemented in the WSS. The implementation of safety systems is supposed to reduce hazard occurrence and hazardous consequences in case of a WSS unsafe disruption. To assess this reduction, we preconise the use of the safety integrity levels standards. The implementation of the safety systems/devices is undertaken on the ground of the multi-barriers safeguard approach. The "Water Contamination Hazard" is considered in the paper. A case study is presented, assessed and conclusions are drawn. The methodology presented in the paper and the results of the case study assessment will contribute to the decision-making regarding the upgrading of the safety and the performance of the WSS. [ABSTRACT FROM AUTHOR]

The development of appropriate methods by which to assess the functioning of gas pipelines helps limits the consequences of disasters, in that way protecting users better. Assessment methods of this kind are presented in this paper, which advocates the integrated risk area identification method. The risk taken account of is understood to be a function of the probability or frequency of occurrence of undesirable events, and comes with parameters defining the consequences of these events, should they arise, in terms of their magnitude. The level of system vulnerability to events of these types is a factor considered, and the risk calculation is of a kind that encompasses both quantitative and qualitative aspects. The approach taken is regarded as a quick and simple risk-assessment tool applicable to the daily operation of gas networks for a gas company. Specifically, the framework of the research carried out extends to: (1) Estimation of the average cost of failure of gas pipelines in the case of an urban agglomeration in SE Poland; (2) assessment of the level of integrated risk facing the gas-supply subsystem, by reference to the risk area identification method; (3) failure forecasting by way of regressions with delay; and (4) conclusions regarding failure risk assessment in a gas-supply network, as well as a consideration of prospects. The framework referred here, thus constitutes the basis for both analysis and assessment of the safety of a gas-supply system. [ABSTRACT FROM AUTHOR]

Analysis and assessment of the reliability and safety of a gas-supply system is a key issue, given its status as critical infrastructure. A gas-supply system is characterised by continuous operation and a consequent need to achieve a high level of operating reliability and safety. Such a system has its unique aspects, with particular elements having their different functions while also simultaneously interacting in the context of the integral whole. In such circumstances, risk analysis can prove useful in planning activity to prevent damage, and also in the devising of rescue scenarios. Thus, the purpose of the analysis presented here has been to supply the information that is necessary in decision-making relating to risk reduction. One of the most comprehensive assessment methods is based on the expected value of gas shortage. Basic formulae with which to determine a generalised indicator of system reliability are also presented, with risk viewed as synonymous with the unreliability of gas supply. This paper then proposes a method by which an indicator of the expected efficiency of operation may also be determined as the quotient of chance and absolute risk. The thinking in this article has been developed on the basis of data from a real gas-supply system, while the computational methods deployed allowed applications to draw conclusions regarding possible modification of the expected gas shortages method. [ABSTRACT FROM AUTHOR]

Contemporary risk assessment makes reference to current world trends, whereby there is increased emphasis on safety. This paper has thus sought mainly to present new approaches to failure risk assessment where the functioning of a water distribution network (WDN) is concerned. The framework for the research involved here has comprised of: (a) an analysis of WDN failure in regard to an urban agglomeration in south-east Poland; (b) failure rate analysis, taking account of the type of a water pipe (mains, distribution, service connections (SC)) and months of the year, with an assessment of results in terms of criterion values for failure rate; (c) a determination—by reference to analyses performed previously—of the compatibility of experts' assessments in terms of standards of failure and obtained results, through rank analysis; and (d) the proposing of a modified Multi-Criteria Decision Analysis with implementation of an Analytical Hierarchy Process, to allow failure risk assessment for the WDN to be performed, on the basis of the calculated additive value of obtained risk. The analysis in question was based on real operating data, as collected from the water distribution company. It deals with failures in the WDN over a period of 13 years in operation, from 2005 to 2017. [ABSTRACT FROM AUTHOR]