channel, with very few islands. At each bend, the typical cross section 

 contains a point bar on the inside of the bend and a pool on the outside 

 of the bend, resulting in a triangular shaped cross section. Point bars 

 are the primary area of sediment deposition in a meandering river. Between 

 the bends is a crossing, which typical ly has a wide and shal low cross sec- 

 tion similar to that of a single braided channel. Since the width of the 

 channel in the crossing is simi lar to that in the bend, the average veloc- 

 ity is often greater through the crossing. Maximum depths and corresponding 

 top widths of undisturbed major, side, and high-water channels at 15 study 

 sites with meandering, sinuous, and straight configurations are plotted 

 in Figure 21. A meandering river shifts in the downvalley direction by 



1.0 

 .9 



a -^ 



Z 



S 2 



=> 1 - 



Z 

 Z 

 < 

 X 



u 



T — TTTTTTT ;^ Y 



CHANNEL FULL TOP WIDTH (m) 



120 1 50 180210 



Figure 21. Maximum depths and corresponding top widths of undisturbed major, side, 

 and high-water channels at 15 study sites with meandering, sinuous, and straight 

 conf i gurat i ons. 



88 



