Water-retaining earthwork used to confine streamflow within a specified area along the stream or to prevent flooding due to waves or tides. When a river overflows its banks, there is an immediate decrease in velocity. This results in deposition of suspended mud and, eventually the buildup of an embankment that can contain the river above the elevation of its adjacent floodplain. Syn. 'bund', 'dike', 'embankment', 'stop bank'