Abstract: Both the process and the amount of the water and sediment load flowing into the Jingjiang river reach downstream of the Three Gorges Project (TGP) have changed significantly due to the regulation and storage of the reservoir. Conspicuous erosion in Jingjiang river channel has resulted in river regime changes in parts of the reach, and will consequently influence the embankments and bank protection works along both sides, the river regulation projects and the stability of riverbed, thereby further affecting the flood control, navigation, ecology, environment and the integrated service function of the river in these areas. In this study, movable bed model of the Changjiang River Flood Protection Physical Model was used to study the changes of erosion and sedimentation in this reach at the initial operation stage of TGP. The tendency of river regime changes were predicted as well. Research results will offer technical reference for the planning and design of river regulation and river regime control projects in this river course.

Key words: Changjiang River Flood Protection Physical Model, Three Gorges Project , Tiaoguan bend reach , changes of erosion and sedimentation