Perencanaan Bangunan Pengaman Pantai untuk Mitigasi Abrasi dan Perlindungan Kawasan Wisata Pulau Derawan Kabupaten Berau

Abstract

Derawan Island is one of the leading tourism destinations in Berau Regency that is vulnerable to coastal erosion, particularly along the eastern to northeastern parts of the island. Continuous coastal erosion poses a significant threat to tourism areas, local settlements, and coastal infrastructure located along the shoreline. This study aims to analyze the coastal erosion conditions and determine the most appropriate coastal protection structure as a mitigation measure to reduce erosion and protect the tourism area of Derawan Island. The research employed shoreline change analysis using the Digital Shoreline Analysis System (DSAS), hydro-oceanographic condition analysis, coastal erosion vulnerability and risk assessment, and evaluation of alternative coastal protection structures based on technical and environmental criteria. The results indicate that the eastern to northeastern coast of Derawan Island has experienced coastal erosion covering approximately 1.4 ha, with a shoreline change rate of -1.71 m/year. Hydro-oceanographic analysis shows that waves and ocean currents play a significant role in sediment transport processes, thereby influencing shoreline dynamics. Based on the evaluation of alternative coastal protection structures, an offshore breakwater was identified as the most suitable option due to its superior ability to reduce wave energy, control coastal erosion, and accommodate environmental considerations while maintaining tourism activities. The proposed coastal protection concept consists of a series of offshore breakwaters connected by a causeway, strategically located in areas experiencing the most severe erosion. The findings of this study are expected to provide a scientific basis for coastal protection planning and contribute to the sustainable management of the coastal tourism area of Derawan Island.