With ongoing climate change, new threats appear to the operation of water supply systems (WSSs), which are related to the amount of available drinking water resources, its quality, the operation of existing water supply infrastructure and changes in consumer behavior. The paper presents a bibliometric analysis of the state of knowledge on the impact of climate change on the failure of water supply infrastructure. The bibliometric analysis was performed based on the VOSviewer program. The results of the analysis indicate current research trends in this area around the world and allow the identification of strengths and weaknesses. Most research concerns the identification of factors related to the impact of climate on the failure rate of water distribution systems. A popular research topic was also the prediction of water supply network failures, taking into account the impact of climatic factors. The main research gap is determining the impact of climate change on water quality. The acquired knowledge can be used by water companies, policy-makers and other researchers to plan adaptation strategies to climate change, which pose new challenges for the operation of water supply systems. The conducted bibliometric analysis also allowed for identifying research gaps.

Modern management of water supply systems is based on a preventive strategy consisting of the prevention of failures and crisis situations. Water pipe failures resulting in a lack of water supply for a long period pose a threat to the water consumers safety. The aim of the work was to present the methodology and develop a risk map of lack of water supply to consumers. The article presents a failures simulation of the main pipes transporting treated water from the water treatment plant to the city carried out using the EPANET 2.0. software. The simulation results made it possible to determine the consequences of failures by determining the number of inhabitants (consumers) affected with lack of water supply as a result of failure of the main pipes near the water treatment plant WTP which, together with the failure rate, were used to prepare risk maps of lack of water supply. The developed method was presented on the water supply network located in Central and Eastern Europe. It was found that the highest risk of lack of water supply is related to the failure of the M3 main pipe, which transports water to the eastern and north-eastern parts of the city. It is recommended to modernize the M3 main pipe, which will reduce the number of failures resulting in a lack of water supply.

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.

New requirements for water supply companies enforce the implementation of risk analysis and assessment methods on many levels of their operation. The approach recommended by the World Health Organization and the European Commission based on threats prevention from intake to water consumers is becoming more and more popular. The paper presents a three-parameter risk matrix that can be used for the implementation of Water Safety Plans. It was also proposed to use the grey systems theory, which allowed for the extension of the risk matrix analysis method. The grey systems theory makes it possible to make decisions in the lack of complete information. This may be of particular importance in the small water supply systems safety analysis where monitoring and management capabilities are limited. The developed method may constitute basis for procedures to ensure the water supply safety for water supply system operators, burdened with more and more obligations resulting from both national and European regulations.

The water distribution subsystem is the most failing subsystem included in the water supply system. One of the main consequences of water supply failures is the lack of water supply to consumers, which is always very onerous. The paper presents a method of determining the conditional probability that a break in the supply of water to consumers of a certain duration will be caused by a specific type of failure. The result of the work was to identify water supply network failures that result in the longest water supply suspension time. The method was presented on a real water supply system. In order to reduce the incidence of long-term interruptions in water supply, water supply companies should mainly continue replacing gray cast iron pipes with thermoplastic materials. Actions taken to increase the safety of drinking water supply meet the current standards for the safety of drinking water, developed by the World Health Organization and the European Union.