Aiming at the problem of local pebble siltation obstructing navigation during the recent scouring process of Lujiahe,the observation data are analyzed and a two-dimensional mathematical model is established,and the maintenance dredging scheme of the channel is put forward and demonstrated.The results show that the local pebble deposition in the channel is mainly caused by the local pebble transport in the process of scouring,and the local channel conditions can be improved by reasonably controlling the location and extent of maintenance dredging,while the overall scouring and silting and flow conditions of the reach will not be greatly affected.This paper has reference values for channel maintenance of sand-gravel river downstream TGD,and is also helpful for dredging scheme design of similar reach.