MODELING URBAN FLOODS USING 2D HYDRODYNAMIC MODEL AND ESTIMATING BUILDINGS IMPACT OF FLOOD IN MAMPANG RIVER JAKARTA

• Main Author: Yunita, Ratna
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/81199
• Institution: Institut Teknologi Bandung

<p align="justify">Flooding often occurs in urban areas due to the reduction of water storage and infiltration areas. This results in a decrease of water availability and contributes to the increasing potential for urban flooding from year to year. Jakarta is a city with the potential for flooding events because of its location in a downstream area and the numerous rivers that flow through it. Mampang Sub-Watershed is one of the sub-watersheds in Jakarta that frequently experiences flooding events. Approximately 90% of the Mampang Sub-Watershed area is in South Jakarta, with the remaining portion in Depok. The Mampang River is the main river in the Mampang Sub-Watershed that overflows every year. This study aims to analyze the flood hazard of the Mampang River for the return periods of 2, 5, 10, and 25 years, using hydrological and high-resolution remote sensing data (LiDAR) as the main data sources. The research methodology involves 2D hydrodynamic modeling through stages of hydrological analysis, 2D hydrodynamic flood modeling, and spatial flood hazard analysis. The validation results of the model against the historical data of the 2020 flood depth show an NSE (Nash-Sutcliffe Efficiency) value of 0.84 and RMSE (Root Mean Square Error) of 0.14. In addition, the model's area results represent 55% of the flood event area in 2020. Analysis of flood hazard levels based on the Head of the National Disaster Management Agency (BNPB) Regulation Number 02 of 2012 regarding General Guidelines for Disaster Risk Assessment shows that in return periods of 2, 5, and 10 years, it is dominated by the Low class (<0.76 m). Meanwhile, in the 25-year return period, flood hazards increase, dominated by the Medium class (0.76 - 1.5 m) with an area of 401,353.44 m2. The land use class most affected by floods is housing, especially small houses. The affected houses are 2,606, 2,726, 2,770, and 2,832 buildings in return periods of 2, 5, 10, and 25 years. This flood hazard modeling provides insights that can be used to improve disaster risk management and mitigation strategies.<p align="justify">