Since the 175m experimental impoundment of the Three Gorges Reservoir，the problem of pebble and gravel siltation has continued to exist in the local key obstruction shoal in the upper section of fluctuating backwater area under new water and sediment conditions，which has adversely affected the channel conditions of backwater surface profile and there are certain hidden dangers in the safety of ship navigation.Since the catastrophic flood season in 2020，the shallow moraine in Yudong waterway(Zhongdui/Diaoyuzui)in the upper section of fluctuating backwater area has been silting up year by year.Based on the background of the key beach hazards in this section，this paper analyzes the characteristics of scouring and silting in key obstruction shoals and the causes of navigation obstruction，puts forward targeted maintenance and dredging schemes，and analyzes the dredging effect.From the perspective of the effect of maintenance dredging after completion and the channel conditions of the river section，the channel width，water depth and bending radius of the key obstruction shoal in Yudong waterway (Zhongdui/Diaoyuzui) have been improved，and the channel conditions have improved significantly.