In view of the impact of the implementation of the Hengsha east siltation and reclamation Phase 8 project on the nearby waters,the river regime analysis method is used to quantitatively analyze the changes of water,sediment and topographic erosion and deposition during 2017-2021 after the implementation of the project.The results show as follows:1) In the flood season,the diversion ratio of ebb tide in the North Passage is between 52.4% and 55.9%,and there is no overall trend change.2) North Passage,the lower section of North Channel and Hengsha Shoal continue the erosion and deposition trend since 2010.3) The thalweg of the lower section of North Channel is southward and smoother.4) Hengsha channel volume remains stable.In addition,the head of the N23 submerged breakwater and the northern edge of the Hengsha shoal near the submerged breakwater are scoured obviously,which requires continued attention.