Parts of the Southeastern United States have recently witnessed the impacts of frequent, unprecedented rainfall events coupled with stormwater drainage systems which do not provide the necessary capacity and conveyance to handle them. Case studies, such as the 2010 and 2021 Tennessee floods, provide snapshots of how truly unprecedented significant rainfall events and floods can be. Design engineers and land developers have challenges when selecting the appropriate stormwater management best practices. An understanding of the probabilistic risk of extreme storm events is necessary to formulate decisions about the level of service of stormwater facilities and conveyances that are appropriately conservative. Revisions to stormwater manuals, the adoption of prudent planning and design policies, and an incorporation of data from the upcoming publication of NOAA Atlas 15 are tools that communities can use to protect life and property from low-probability and high-impact storm events. Although policy and design decisions will never eliminate the risk of an extreme storm event, careful planning in both the private sector and public forum will aid in the future resiliency needed within stormwater systems to protect lives and recover more quickly.