Abstract-Simulation based decision making tools, such as simulation cloning, "what-if" analysis, and etc., has being a beneficial way to analyzing of multiple alternative scenarios, however, there is no guarantee that a simulator could obtain a feasible scenario meeting the flood mitigation requirements, let alone an optimal one. Motivated by J. R. Marden and his colleague's work "cooperative control and potential games", a novel technique, the alternative scenario selection game, was proposed in this paper to solve the flood mitigation optimization problem, in which the alternative scenario selection problem was modeled as a potential game with appropriately defined players' utilities. A SAP (Spatial Adaptive Play) based learning algorithm for the potential game with suboptimal Nash equilibria was introduced to help all players to converge to a consensus after finite iteration steps. Case study and performance evaluation shows that the proposed technique is feasible and stable, within a few iteration steps, all players could quickly reach the goal of the expected flood peak point.