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.

The consequences of climate changes are felt by society every day. A sudden increase or decrease in air temperature, increasingly frequent, extreme weather phenomena can cause enormous economic damage to countries and cities. The occurrence of random weather phenomena and their negative impact on technical infrastructure nowadays are the basic problem related to ensuring the safety of the functioning of each system. Climate changes and significant air temperature amplitudes have a direct impact on the functioning of the critical infrastructure of cities, which includes collective water supply systems (CWSS). The paper presents the impact of climate change on the failure of a water supply network. Correlation between failure rate and air temperature was determined. This was used to determine the number of failures for the near 2036–2050 and distant 2086–2100 future in terms of climate change (temperature increase). The results confirm the thesis known from the literature that the failure rate decreases as the temperature increases. For forecasted periods as a result of temperature rise due to climate change, the reduction of the number of water pipe failures is expected in the range of 1.22% to 2.35% for the 2036–2050 period and from 2.96% to 8.66% for the 2086–2100 period, depending on the development of Representative CO₂ Concentration Scenarios (RCP). The decrease in the total number of failures will have an impact on the increase in the reliability and safety of water supply to consumers.

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.

Since 2017, risk assessments for water intakes in Poland have provided the basis for decisions to establish indirect water protection zones. The preventive, risk-based approach and the related risk minimization measures are required under the provisions of the Drinking Water Directive (DWD) of the European Parliament and of the Council of 16 December 2020 on the quality of water intended for human consumption. This approach is in line with the World Health Organization (WHO) recommendations for water safety plans. The aim of this study was to present a methodology and to carry out a risk assessment of the threats to surface water intakes, which in Poland, should be completed by the end of 2022. Risk assessments were performed for four onshore-type surface water intakes located in south-eastern Poland. The results were presented in aggregate form, which enabled clear presentation and conclusions. It was found that the greatest risks are associated with seasonal changes in water quality (mainly high turbidity and water blooms), unregulated sewage management, the occurrence of floodwater flows and catastrophic events caused by the potential failure of wastewater treatment plants. Based on the results of the risk assessment, the need to establish new, or to adjust the existing, protection zones for the analyzed water intakes was identified.

One of the factors limiting the possibility of the development of urban agglomerations is access to drinking water. Due to progressive climate change, the available water resources are limited. The paper proposes new indicators of limiting the development of agglomerations related to the availability of water resources and the production capacity of water treatment plants, a method for assessing the diversification of water resources (using the Pielou index), and a water loss balance was prepared based on International Water Association (IWA) standards. On the basis of the obtained results, the potential increase in the number of inhabitants indicators (∆P_R, ∆P_P) and the time for the development of agglomeration indicators (T_R, T_P), the directions of development of the studied agglomerations in terms of the possibility of water supply were indicated. The main problems were reducing the amount of water losses, appropriate management of the migration policy of the population, and the necessity to look for alternative sources of water.