Transverse velocity distributions in channels with emergent bank vegetation

Defining hydraulic habitat conditions in rivers requires prediction of local flow velocities, which are strongly influenced by the presence of emergent vegetation along the banks. Previously proposed methods for describing the transverse variation of depth-averaged velocity away from the vegetation edge are shown by comparison with independent laboratory data to be inadequate. One of the methods is modified on the basis of new data to provide realistic descriptions over a wide range of conditions. The new method enables prediction of the maximum velocity in both wide and relatively narrow channels, the apparent shear stress at the vegetation interface, and the variation of velocity from the vegetation boundary to the point where the maximum velocity occurs. Copyright © 2008 John Wiley & Sons, Ltd.