The large reservoirs of the Mainstem System help provide a dependable flow to maintain the navigation channel year-round, and are capable of halting most of the river's annual freshets.
Os grandes encoros do Mainstem System axudaron a proporcionar un caudal confiable para manter a canle de navegación durante todo o ano, e foron capaces de deter a maioría das crecidas anuais do río.