The Mississippi River and Tributaries protection system is designed according to the Project Design Flood (PDF), or the largest storm series with a reasonable chance of occurrence over the Mississippi River Basin. This report considers a new approach to generate hypothetical extreme flow conditions for the entire Mississippi River Basin. Utilizing recent advancements in computer modeling and climate science, a vector-based continental-scale river routing model was developed for the entire Mississippi River Basin. Daily flows within all river segments were computed for 1.2 million river reaches over the time period of 1950 through 2099 and for 16 different climate scenarios. An ensemble of varying climate simulations were executed using the Routing Application for Parallel computatIon of Discharge river routing model. The 16 projections were from the Coupled Model Intercomparison Project, Phase 5, climate model projections. Daily flow results for the 65 key locations were analyzed for the historical (19502005) and the projected (20062099) time periods. Results indicate that the hydrologic conditions of the Mississippi River are not stationary and that discharges associated with the extreme events are projected to increase in the future.