PENGARUH BANGUNAN REVETMENT TERHADAP PERUBAHAN GARIS PANTAI HAYALAN DI DESA SALUBOMBA KABUPATEN DONGGALA

Abstract

Hayalan Beach, located in Salubomba Village, Senter Banawa District, Donggala Regency, Central Sulawesi, is a tourist destination situated 10 KM south of Donggala City. Over time, the amount of sediment transport along the Hayalan Beach coastline indicates changes in the shoreline, and in addition to the increase in sediment transport, coastal erosion is also occurring. This research aims to determine the changes in the Hayalan coastline when using GENESIS software modeling for the next 5-10 years, as well as to determine the amount of sediment transport at Hayalan Beach. The research method involves numerical simulation designed to predict coastline changes, using 2 scenarios: scenario 1 without coastal protection structures and scenario 2 with coastal protection structures. The necessary input data includes regional map data, wind, waves, sediment, and 15-day tidal data. From the wave hindcasting results, a significant wave height (Hs) of 1.10 m and a significant wave period of 22.656 s were obtained. From the coastline change simulations conducted using GENESIS software, two types of coastline changes occurred: accretion (addition to the coastline) and abrasion (reduction of the coastline). This is shown in scenario 1 (2025-2030) without coastal protection structures, where a maximum accretion of 31,738 meters and a maximum abrasion value of -56.496 meters occurred. In scenario 2 (2025-2030) with coastal protection structures, a maximum accretion of 30,738 meters and a maximum abrasion value of -55,815 meters occurred. For the 5-10 year prediction, in scenario 1 (2025-2035) without coastal protection structures, a maximum accretion of 27,790 meters and a maximum abrasion value of -56,386 meters occurred, while in scenario 2 (2025-2035) with coastal protection structures, a maximum accretion of 26,090 meters and a maximum abrasion value of -55,975 meters occurred