What Is a Distributary? The River's Extension

A distributary is a channel that branches away from a main river, carrying water outward—typically in a delta. Unlike tributaries (which flow into a river), distributaries flow out of it, distributing flow across wetlands, marshes, and multiple mouths to the sea. Famous examples: the Mississippi's Atchafalaya, the Nile's Damietta and Rosetta branches, the Ganges-Brahmaputra's myriad channels.