Run-off within the confines of a channel. See L. B. Leopold et al. (1994). Compound channel flow occurs in meandering channels, where the magnitude and directions of the main channel and the upper layer differ, causing sizeable internal shear stress, and a consequent loss of energy. For meandering compound channels the important parameters affecting the boundary shear distribution are sinuosity (Sr), amplitude (a), relative depth (β‎), and the width ratio (α‎) and the aspect ratio (δ‎); see Khatua and Patra (2007) Procs 5th Australian Stream Manag. Conf. Compound channel flow also occurs during floods, when velocity differs between the main channel and the flooded area. See Helmio (2002) J. Hydrol. 269 and Fukuoka et al. (1999) J. Hydrosci. & Eng. 17, 2.