Climate change is increasingly recognized as a major threat to the safety and sustainability of drinking water systems worldwide. Extreme weather events such as heat waves, heavy rainfall, prolonged droughts and floods significantly impact water sources, treatment processes and distribution networks, leading to changes in water quality parameters and increasing operational challenges. This thesis investigates the impact of climate-induced extreme weather events on drinking water quality, focusing on changes in key parameters and risk management strategies in water supply systems. A multi-method approach was used, including an in-depth literature review, surveys of water service managers in Italy and Vietnam and an in-depth case study in Brescia, Italy. The study highlights the increasing frequency and severity of climate-related challenges in drinking water systems. Key concerns include bacterial contamination, high levels of turbidity in source water, and increased water temperatures that accelerate chemical reactions and bacterial activity in distribution networks. The study also considers the integration of real-time monitoring systems, which have transformed water quality management by enabling immediate risk assessment and response. In this context, operational monitoring, as outlined in D.Lgs. 18/2023, ensures ongoing compliance with safety standards by focusing on the functionality of risk control measures, unlike traditional analytical monitoring, which provides long-term water quality assessments. A key advance in this area has been the development of Early Warning Systems (EWS). By continuously monitoring pH, conductivity, and turbidity, EWS can quickly detect unexpected changes in water systems. For example, sudden increases in turbidity can indicate contamination or structural problems, prompting immediate intervention. These systems not only enhance response capabilities but also simplify long-term monitoring programs by prioritizing critical indicators. Furthermore, EWSs can be integrated with automated controls, such as valves or flushing systems, to mitigate risks in real time. However, the effectiveness of such systems depends on robust data management and interpretation, requiring statistical methods to process raw data into actionable insights. The creation of comprehensive databases and control charts is essential for informed decision making and increased reliability of the supply system. Through surveys of water service providers in Italy and Vietnam, the study identified regional variations in climate risk perception and adaptive capacity. While both countries face similar climate-induced challenges, their ability to mitigate risks differs due to differences in regulatory frameworks, financial resources, and technological advances. Italian water providers emphasize regulatory compliance with European Union directives on water quality and emerging contaminants, while Vietnamese regulators emphasize infrastructure constraints and the urgent need to invest in resilient water treatment technologies. A case study in Brescia, Italy, provides a detailed examination of the direct impacts of climate change on drinking water systems. Data analysis shows that heavy rainfall events are correlated with spikes in turbidity and bacterial indicators, requiring increased disinfection efforts and tighter microbiological controls at the source. To address these challenges, this thesis proposes several adaptation strategies to enhance the resilience of drinking water systems. First, real-time water quality monitoring should be integrated with advanced sensor technologies and data analytics to enable early detection of contamination and fluctuations in key parameters. Second, microbial monitoring technologies should be improved by implementing new detection tools that significantly reduce incubation times, enable faster bacterial identification, and improve response times compared to conventional methods.