IVL Swedish Environmental Research Institute conducted three consecutive workshops with relevant stakeholders from the drinking water sector in Sweden. Researchers from IVL, led by Johan M. Sanne assessed the workshops. The workshops included a stress-test, based upon a scenario of microbial contamination of water, either raw water or distributed water, due to flooding as a consequence of heavy rain. The stress-test was considered a good tool for self-assessment, as an input to crisis preparation. The stress-test was considered useful as a complement to current reporting formats to politicians, not at least because it visualizes resilience in different phases of the cycle. Important outcomes include the learning process as well as a list of improvement measures, including an evaluation or priority ordering.