Flood evacuation routes mapping based on derived-flood impact analysis from landsat 8 imagery using network analyst method

Reported by National Disaster Response Agency of Indonesia (BPBD) as many as 94 dies, 149 injured, and more than 88 thousands homeless caused by floods in 2018. Besides bringing casualties to people and environment, the floods also affect the damages to transportation infrastructures in which vital to disaster emergency response operation e.g. evacuation process. Due to the complex impact of current disaster, the demands of providing a short-term response increases accordingly. Therefore, this research proposes a prototype of flood evacuation route utilizing network analyst method. The network analyst method particularly focus on finding alternative route based on time and distance. This research uses a flood simulation model derived from Landsat 8 imagery and terrain data. Subsequently, the simulation model divides the flood severity based on the depth which consist of < 0.3 m (slight), 0.3-0.5 m (moderate), and > 0.5 m (serious) in order to generate an impact analysis regarding the estimation of damages and casualties. In order to resemble the real situation of flood, barriers (e.g. flood area) are applied into the finding evacuation route procedure. Thereby, the estimated evacuation route can be executed considering the safest and fastest way. Moreover, some comparisons between before and after flood are conducted in order to know the effectiveness of evacuation routes. By such comparison proves that network analyst enables to support disaster management operation with respect to handling the evacuation procedure.