^:^^^^ 



PLAN VIEW 



SECTION A-A 



Figure 18. Schematic diagram of the plan view and cross section of a typical 

 sp li t channe I r i ver . 



undisturbed major, side, and high-water channels, at four split channel 

 study sites, are plotted in Figure 19. Sediment discharge is typically less 

 than that of a braided river. Bed load is deposited at low flow to form 

 gravel bars along the sides or in the middle of the channels. These bars are 

 typically more erodible than the banks. The bars, rather than the banks, are 



■ 



eroded during subsequent floods, resulting in a laterally stable channel. 



Meandering Configuration . A meandering river winds back and forth 

 within the floodplain (Figure 20). The ratio of the channel length to the 

 downvalley distance is called the sinuosity ratio, or sinuosity. Meandering 

 rivers have a sinuosity greater than 1.5. Flow is contained in a single 



85 



