The Impact of Canal Construction on the Hydro-Morphodynamic Processes in Coastal Tidal Channels

Canals have played a significant role in promoting the prosperity of the shipping industry worldwide. Meanwhile, canal construction can alter the hydro-morphodynamic processes in coastal tidal channels. The Fangchenggang Canal is an extension route of the Pinglu Canal, which connects southwestern regions to the Beibu Gulf in the South China Sea by cutting across approximately 20 km of intertidal and dry land of the Qisha peninsula. A two-dimensional numerical model based on MIKE21 has been established to investigate the variations of tidal current structures and sediment transport characteristics. The maximum flow velocity within the main channel increases up to 1.18 m/s in the marine section. A bidirectional flow pattern has been observed in the land excavation segment. Numerical simulations of the sedimentation processes demonstrated potential erosion in the land excavation section due to the increased bed shear stress. The present study shares useful insights into the response mechanism of hydro-morphodynamic processes under canal construction. The quantitative simulations would support the environmental assessment and route planning of canal projects.