Taking a dock project on the left bank of the Beijiang River as an example,the finite volume method is used to establish the one-dimensional hydrodynamic model for the 37.0 km long section of the Shaoguan (II) hydrological station to Mengli hydropower station,and the two-dimensional hydrodynamic model for the 4.6 km long section of the project.A quantitative study is conducted on the differences in flood level,flow velocity distribution,and flood storage capacity of river channels under different construction schemes.The results show that when the flood frequency ranges from once every 50 years to once every 10 years,the increment of flood level is lower than 0.02 m under different schemes.The changes in flow velocity and pattern are mainly concentrated in the local river section from 100 m upstream to 260 m downstream of the dock.However,the changes in high flow velocity areas of the river are relatively small,as well as the changes in the dynamic axis of the main channel.Meanwhile,the actual flood storage capacity of the river has increased under the action of dredging in the harbor.From the perspective of flood safety and cargo safety,scheme 2 is a recommended plan,and relevant research methods can provide scientific reference for similar dock construction plans.