Analyzing Coastline Erosion to Save the Coastal Environment in Makassar

Abstract

Due to the degradation of the beach, the sea level is approaching some of the buildings on Layar Putih beach. Tugu Layar Putih, which used to be accessible on foot, has been submerged. The condition of the beach looks damaged, especially at Tanjung Layar Putih, which is currently unattended and abandoned. This has a negative impact on the environment and can lead to flooding. The area from Tanjung Bunga Metro to Losari Beach is also experiencing high sedimentation. The high sedimentation is caused by the deposition of sediment carried by river currents in the area of the Jeneberang River estuary, as well as the presence of sea currents at the mouth of the river in sufficient volume. A sediment transport capacity that is not in balance with the supply is the process of beach retreat. This process is known as coastal erosion and causes changes in coastal morphology in addition to abrasion and estuarine sedimentation (accretion). While the coastal area of Makassar City is one of the beach tourist attraction areas located in Makassar City. The purpose of the study was to determine the causes of coastal erosion in order to find strategies to save the coastal environment in Makassar in order to prevent further coastal damage. The research methodology analyses beach typology, waves and sediments. The results of the study were obtained coastal sediment type clay type which has a high cohesion value, the wave direction is generally from the West and North towards the South, the most frequent wave height that can be analyzed by STWave CEDAS Genesis 4.03 Numerical Modelling for 10 years of modelling is 1.64 meters, the dynamics of shoreline change is quite balanced between erosion and accretion, the average wave period is 4.599 seconds, the sediment deposition rate is 1.66 cm/sec and sediment transport is 54,975,398.47 meter3/year. The sediment deposition rate is in a transitional (intermediate) condition so that sediment transport does not experience a significant decrease in transport. The conclusion from this study is that the beach tends to have more potential for sedimentation (accretion) than erosion (abrasion), due to the type of sediment and the construction of buildings on reclaimed land in the northern part of the study site.