GROIN PLANNING AS PROTECTION OF GLAGAH BEACH, KULON PROGO REGENCY, YOGYAKARTA SPECIAL REGION

• Main Author: Thufailah Qurratu'ain, Hasni
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/69963
• Institution: Institut Teknologi Bandung

Coastal areas are used for human activities, residential, tourism, fishing, and other public facilities. Each coastal area has its characteristics and can be damaged by human activities or natural influences. Glagah Beach, located on the coast of Kulon Progo, is a sand beach with a steep slope so that the tidal waves towards the beach cause longshore sediment transport, which causes the coastline to retreat and the facilities around the beach to be damaged. To overcome this problem, it planned to build groins around the coast. Tidal analysis using the Harmonic Analysis of Admiralty and Least Square method obtained HHWL values of 1.339 m and LLWL of -1.276 m. Wind data analysis is used for wave forecasting using the Shore Protection Manual method (SPM 1984). The dominant wave directions are south and southeast. Wave modeling using Delft3D on the dominant wave direction with a return period of 50 years. The wave height around the building is 3.92 m. From the calculation results, planning a 5.4 km groin requires 19 groins with a length of 83.33 m and a distance between groins of 250 m. The plans included groin dimensions, peak elevation and width, calculation of the number and thickness of shields, alternative protective materials a-jack, terapod and rubble stone, and budget plans. The cost required in planning the groins at Glagah Beach is Rp. 50,368,000,000,000.00.