A river characterized by multiple interlacing channels separated by temporary islands and bars of sediment. Braided rivers typically carry high sediment loads and exhibit rapid channel changes.
A braided river is a type of fluvial system characterized by a network of multiple, shallow channels that repeatedly split and rejoin around bars and islands of alluvial sediment. Braiding typically occurs when a river has a high sediment load relative to its transport capacity, steep gradient, erodible banks, and highly variable discharge. Classic examples include glacial outwash rivers (e.g., rivers in Iceland, New Zealand's Canterbury Plains, and Alaska's Copper River), which receive abundant sediment from glacial erosion and meltwater. The channel pattern is highly dynamic, with bars forming, migrating, and being eroded during individual flood events. Braided rivers tend to be wide and shallow, with unstable banks that make them challenging for infrastructure such as bridges and pipelines. The high permeability of braided river deposits makes them important aquifer systems; many cities in mountainous regions depend on braided river gravels for water supply. Braided channels are often ecologically productive, with the diversity of aquatic habitats (pools, riffles, backwaters) supporting fish spawning and diverse macroinvertebrate communities. The transition between braided and single-thread (meandering) patterns is governed by the relationship between slope, discharge, and sediment size, described by empirical channel pattern discriminant functions.