FLOOD HAZARD ANALYSIS BASED ON GEOGRAPHIC INFORMATION SYSTEM (GIS) AND FORWARD MODELING OF TIME LAPSE MICROGRAVITY FOR MEGAPOLITAN AREA CASE STUDY BANDUNG RAYA, WEST JAVA

• Main Author: Anugrah Leman, Jonathan
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/61946
• Institution: Institut Teknologi Bandung

Floods are one of the common disasters that occur in big cities that are growing rapidly. This can lead to very large losses. The megapolitan city of Bandung Raya is one of the big cities in Indonesia that is not spared from the flood disaster. This research was conducted with the aim of reducing the losses caused by flooding by predicting the increase in flood-prone areas in the next few years. In this study, an analysis of flood-prone areas was carried out and an analysis of the increase in flood-prone areas in the megapolitan area of Bandung Raya. For the analysis of flood-prone areas, a Geographic Information System (GIS) approach is used through scoring and overlay methods. The data used for the application of this method are rainfall data, slope data, land use data, and soil type data. The results of the analysis of flood-prone areas show that the megapolitan city of Bandung Raya is an area with a moderately vulnerable classification dominance, with several surrounding sub-districts, namely Lembang which is an area with a moderately vulnerable classification dominance, and Dayeuhkolot, Margahayu, Rancaekek, and Cimahi City areas which are areas with vulnerable classification. To predict the increase in flood-prone areas, groundwater level subsidence data and time-lapse microgravity data are used. This data together with geological data and other supporting data are used to model the distribution of flood-prone areas in the next few years through the SimQURING forward modeling software. The output of modeling is in the form of groundwater extraction discharge parameters, hydraulic conductivity, specific storage, aquifer depth, aquifer thickness, porosity, and rock density. The modeling was carried out in 5 places in the megapolitan city of Bandung. The modeling results show that the land surface in the study area decreases consistently every year at a rate that varies from 36,01 to 389,86 mm per year. From this research it can be determined that the area of Cimahi City with a subsidence of 366,27 mm/year and Dayeuhkolot District with a subsidence of 389,86 mm/year has the greatest potential for flooding.