Abstract:After the operation of the Three Gorges Reservoir,the unbalanced erosion and deposition occurred in the bifurcation reaches of the middle and lower reaches of the Yangtze River,and the bifurcation relationship was significantly adjusted,resulting in the difference of navigation-obstruction characteristics of the corresponding shoals. Based on the research of braided reach riverbed evolution and the navigation obstruction characteristics of the shoals in the middle and lower reaches of the Yangtze River,this paper discusses the channel management ideas of the braided reach. The main conclusions are as follows:1)The shallow reach of the braided river in middle and lower Yangtze River has occurred further scour depth after the impounding and operation of Three Gorges project,associating with the shrinks of bottomland and the adjustments in the characteristics of channels. 2)The flood diversion ratio of the main stream in the branching section decreases,the flood diversion ratio falling ranges is less than low water for the bending and straight braided river,but the flood diversion ratio falling range is less than low water for the goose head shape braided river.3)The controlled intensity of the navigation main braided channel on distributaries tends to decline after Three Gorges Reservoir impoundment,the inlets of the navigation main braided channel often staggered or scattered bad shoals form,such as channel conditions deterioration,shallow shoal hinders navigation. 4)To maintain or improve the channel scale,the branch reach can be controlled step by step,and the regulation measures such as beach control and guidance,edge and center beach shaping or branch control technology can be implemented.