Continuity of Operations Planning (COOP) is actions taken before, during and after a disaster to maintain the delivery of an organization's essential services. The application of COOP in public health is necessary to save lives and protect population health when disaster strikes. However, COOP decision-making and COOP decision support technology are under-explored in the public health domain. This work approaches the problem of designing a COOP decision support system for a large municipal public health agency using scenario-based design. Through a series of meetings and informal interviews, we developed a set of 12 scenarios of use for public health decision-making roles during a pandemic. These scenarios were validated as reliable, useful and acceptable by professional public health COOP planners. The results of this work show scenario-based design can be a powerful tool in designing decision support systems for public health leadership information needs during a crisis.