However, high and low water cycles of the Missouri – notably the protracted early-21st-century drought in the Missouri River basin and historic floods in 1993 and 2011 – are difficult for even the massive Mainstem System reservoirs to control.
Con todo, os ciclos de crecidas e secas do Missouri —en particular a prolongada seca de principios do século XXI na conca do Missouri e as inundacións históricas de 1993 e 2011— son difíciles de controlar mesmo para os grandes encoros do Mainstem System.