helical flow
A continuous corkscrew motion of water as it flows along a river channel. It has been explained by the tendency of the thalweg to flow in a straight line, so that it ‘hits’ the outer banks of a meander and causes a ‘head’ of water to build up at that point. To compensate for this, a return flow develops across the channel. Note, however, that other geomorphologists have suggested that helicoidal flow actually causes the development of meanders. Helicoidal flow is particularly associated with sinuous and meandering river channels.
