Study of groin structures effectiveness for against abrasion in Padang Beach

Abstract

This study was conducted to evaluating the performance of existing coastal protection structure to restrain the rate of erosion as a result of the influence of hydrodynamics process. Condition that reviewed was in form of distance shoreline as simulation results to initial reference line before. STWAVE module used to determine wave height at near shore as transformation of deep water wave height that determined before from SMB method. One Line Model was conducted to get shoreline change in each time step calculation. Model consists of two conditions, with the absence of coastal structures and with structure respectively. The simulation result show that potential erosion occurs at Batang Arau river mouth with no protection structure. Large erosion predicted around 59.04 meters from the shoreline position early. With coastal protection, model result obtained sedimentation of 7.33 meters coastline from its initial position. This occurs at a distance of 475 meters from the boundary domain. Modeling results also showed erosion is 18.39 meters at a distance of 250 m from the boundary domain. This is likely due to the limited modelling conditions that without reviewing of littoral transport direction that occurred in perpendicular to the coast. Result study show that the presence of a groins in Padang coasts looks already quite effective to maintain the shoreline of the littoral transport direction, however the installation of groins seemingly did not give significant meaning in the addition of the coastline.