The Susquehanna River Basin Commission tasked us with developing a custom inundation mapping viewer that was publicly accessible as a means to communicate flood hazards to reduce flood losses and increase awareness. We delivered a powerful decision-making tool for emergency managers and the general public. The web-based application provides personalized risk reports for any location affected by flooding and allows a user to see the potential risk to property, structures, or landmarks while also viewing the latest observed and predicted river conditions.