Evaluations on coastal topographical changes at Hualien Coast, Taiwan

Coastal topographical changes at Hualien Coast, downdrift of Port of Hualie n, Taiwan, after the construction of an extended breakwater are closely eva luated based on the results from continuous field survey data, a statistica l 2-D empirical eigenfunction model, and a numerical hydrodynamic model for nearshore current fields. Firstly, the analysis from field survey data ver ifies the significant impacts on shoreline changes due to the installation of an extended breakwater. The 2-D empirical eigenfunction model is then ap plied to forecast beach profile changes at the coastal areas assuming no br eakwater installation. Comparisons with surveyed beach profiles successfull y illustrate that the breakwater installation is responsible for giving ris e to accreting northern beaches while eroding southern beaches. The numeric al result further points out that the extended breakwater induces an extra clockwise circulation cell in harbor's lee marine area and it transports se diment towards the harbor in shallower water. Altogether, clear identificat ions on the effects of the breakwater installation suggest that detailed an d reliable evaluations on the coastal topographical changes can be achieved through adoption of the present schemes.