Abstract:The implementation of coastal engineering will change the regional terrain and affect the hydrodynamic forces and sediment transportation. According to the characteristics of the intertidal zone, using semi-empirical Semi-theoretical formula with submerged depth and submerged velocity, we predicted the sediment scouring and silting within the intertidal zone. Base on the 2-D numerical model for the tidal current,and used the modified semi-empirical Semi-theoretical formula, we analyzed the influence from the reclamation engineering of Xuanmen bay on the changes of sediment scouring and silting within the tidal zone.