Suci Purnama Sari
Magister Geography, Geography, Faculty of Geography, Universitas Gadjah Mada, The Special Region of Yogyakarta, 55281, Indonesia

Published : 1 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 1 Documents
Search

Flood Risk Analysis in Gajah Wong River, Yogyakarta City Slamet Suprayogi; Suci Purnama Sari; Husnul Khotimah Setiacahyandari
Jurnal Ilmu Lingkungan Vol 22, No 4 (2024): July 2024
Publisher : School of Postgraduate Studies, Diponegoro Univer

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jil.22.4.1033-1040

Abstract

Evaluation of flood events in an area is essential to minimize its impacts by conducting hydrological and hydraulic river modeling. In 2016 and 2022, the events led to the breach of the Gajah Wong River levee, causing the floodwater to overflow and inundate residential areas, reaching a height of 2 meters. This study aims to analyze the risks posed by the Gajah Wong River overflow, while also identifying the elements at risk due to the potential of flooding. The flood inundation scenario modeling using Hec-RAS requires input such as peak discharge, Digital Terrain Model (DTM), and Manning's coefficient. High-resolution aerial photo extraction is employed to generate DTM and identify buildings affected by flood inundation, in accordance with the flood modeling. The rational method is used to calculate the peak discharge, utilizing the maximum daily rainfall data from 2001 to 2021. The results show that there was a significant expansion of inundation that reached 4.826 m2 for the 2-year and 50-years flood return periods. However, in terms of the flood impact on buildings, an area of 30.350,68 m2 is affected for the 2-year return period, and it expands to 35.439,05 m2 for the 50-year flood.