Climate change will lead to higher temperatures, increased precipitation and runoff and more frequent extreme weather events in Norway. Aging drinking water treatment and distribution systems and sewage systems will be particularly vulnerable to flooding, leading to potential deterioration in the quality of drinking water. Many infectious microorganisms are sensitive to climatic conditions. These factors together will increase the risk and burden of waterborne illnesses. In Norway, little is known about how climate change will affect the safety of drinking water and, thus, waterborne illness and potential needs for adaptation. We will enhance the current understanding of the association between climate, and water quality or waterborne illness by taking advantage of the high quality epidemiological, hydrological and meteorological registries and databases that are available in the Nordic countries but are not often linked. In addition, we will perform quantitative microbiological risk assessment to assess the microbial infection risk and disease burdens associated with climate change impact on water supplies. Our project will be structured as an interdisciplinary collaboration that will bring together top national organizations and actors with extensive experience in the fields of public health, infectious diseases epidemiology, microbiology, hydrology, meteorology, infectious diseases modelling and statistics. The outcome of the project will provide crucial information for understanding the impact of climate change on drinking water safety. This will be central to minimize the risk and reduce harmful effects on the health of the society and waterborne illness burden. Specifically, our results will contribute to identify the priority areas for the recently established Norwegian Centre for Climate Services to disseminate data and generate climate and hydrological indicators to assess the potential negative effects related to drinking water and waterborne illness.