Observations have shown increasing trends in precipitation extremes, with extreme precipitation intensity projected to further increase in the future with increasing temperature and moisture in a warmer climate. While a better understanding of the mechanisms to flood inundation is being advanced using data and models, whether the flood control capacity designed based on the observed climatology is able to mitigate flood events under future climate conditions remains unclear. To address this knowledge gap, we integrated a floodplain inundation model and a water management model within the Energy Exascale Earth System Model (E3SM) for global simulations driven by an ensemble of historical and future climates from the Coupled Model Intercomparison Project Phase 6 (CMIP6). We first compare the modeled flood area under the historical and future climate without water management to identify regions with significant changes in flood area and intensity in the future. Focusing on regions with increased flood risk, we evaluate the future changes in flood frequency and flooded area in simulations with active water management to examine its effects on future changes in flood characteristics. We also compare how the surface water storage is distributed in river channel, floodplain, and reservoirs between the historical and future scenarios. Basin scale analysis suggests that the flood mitigation by water management has various effects across global basins. These results may provide useful insights to guide future dam operations for flood control.