Kuang, C.P.; Huang, J.; Lee, J.H.W., and Gu, J. 2013. Impact of large-scale reclamation on hydrodynamics and flushing in Victoria Harbour, Hong Kong. A three-dimensional (3D) hydrodynamic model for the Pearl River Estuary based on Delft3D is established and calibrated to study the changes in tidal circulation and flushing in Victoria Harbour. The tidal circulation and flushing were simulated by this 3D model under the existing reclamation conditions, including Central Reclamation Phases I, II, and III (CRI, CRII, and CRIII), and Wan Chai Reclamation Phase I (WRI). The model is also applied to predict the hydrodynamic changes after the reclamation of proposed Wan Chai Development Phase II (WDII) to be constructed in 2017. Compared to the coastline in 1975 (before large-scale reclamation), the numerical results show that the following changes have taken place after the existing reclamation: (1) The peak flow at all cross sections along Victoria Harbour decreases by about 9–25%, with an average valu...

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.

Total maximum allocated load (TMAL) is the maximum sum total of all the pollutant loading a water body can carry without surpassing the water quality criterion, which is dependent on hydrodynamics and water quality conditions. A coupled hydrodynamic and water quality model combined with field observation was used to study pollutant transport and TMAL for water environment management in Qinhuangdao (QHD) sea in the Bohai Sea in northeastern China for the first time. Temporal and spatial variations of the chemical oxygen demand (COD) concentration were investigated based on MIKE suite (Danish Hydraulic Institute, Hørsholm, Denmark). A systematic optimization approach of adjusting the upstream pollutant emission load was used to calculate TMAL derived from the predicted COD concentration. The pollutant emission load, TMAL, and pollutant reduction of Luanhe River were the largest due to the massive runoff, which was identified as the most influential driving factor for water environmental capacity and total carrying capacity of COD. The correlation analysis and Spearman coefficient indicate strong links between TMAL and forcing factors such as runoff, kinetic energy, and pollutant emission load. A comparison of total carrying capacity in 2011 and 2013 confirms that the upstream pollutant control scheme is an effective strategy to improve water quality along the river and coast. Although, the present model results suggest that a monitoring system could provide more efficient total capacity control. The outcome of this study establishes the theoretical foundation for coastal water environment management strategy in this region and worldwide.