A discussion paper, prepared by the Resource and Environment Working Group (REWG) of the International Actuarial Association (IAA), examines the natural and human risks to water resource systems. It illustrates these water resource risks by considering three representative systems: those in New York City, Mexico City and India. A generalised risk register is developed that identifies and classifies the risks that all such systems face. Each of the three representative systems is then assessed using the risk register as a starting point. The assessments look at each risk along four dimensions: Likelihood, Scope of Impact, Extent of Impact and Controllability. In each case, the paper touches upon the risk management activities that are already under way to protect the users of the system.