Influence of Wind Force on a Silt-Muddy Coast: Huanghua Harbor Coast, China

Abstract

Huanghua Harbor, a semiclosed harbor with three 13.32–23.4 km-long breakwaters forming a coal port and a general port, is located on the silt-muddy coast of the Bohai Sea in China. Frequent gales cause thick sedimentation at the entrance and in the outer waterway. In this study, a two-dimensional depth-averaged horizontal version of the Delft3D software is used to formulate a hydrodynamic suspended sediment transport and bed evolution model. This model is validated by field data, including the tidal level, the tidal current, and the concentration of suspended sediment. The validated model is applied to predict the suspended sediment transport for three different wind scenarios and the short-term morphological evolution from a gale and a wave. The suspended sediment concentrations largely increase from gale-induced currents and waves. The predictions from the gale and its induced wave in 2003 and in 2012 indicate that suspended sediments are driven by the current along the jetties and can be easily deposited at the harbor entrance and outer waterway after the gale, forming a barrier that would impede normal navigation. The maximum deposition thickness from the gale appears at two port entrances and is approximately 10 times the 1-year deposition thickness under normal weather conditions. This implies that the occurrence of a gale is a key factor for sedimentation in Huanghua Harbor because of its induced current and wave.