An urban flood inundation and damage assessment for disaster risk reduction in Johan Pahlawan Sub-district, West Aceh Regency

Abstract

Residential areas with the high rainfall intensity, flow pattern, and channel condition caused recurrent inundation flood in West Aceh Regency, Aceh Province, Indonesia. The inundation results in the physical damages to the housing components and the number of losses. This study aimed to devise the flood inundation map. The method was field survey to identifying the location, the inundation depth, and the conditions of the exposed residential in 20-24 September 2018. The results showed that the pattern of land flow and drainage conformed with the topography of the area. However, the channel condition, such as bushes, narrowing of the channel, and certain stations with low contoured, caused the vulnerability of inundation. The results showed that the area of the inundation was 26.66 Ha when the flood reached a maximum water level. The inundation varied in the study area, with a duration of 4 to 5 days. Forty housing units in different areas were exposed to the inundation flood, with varying damage conditions depending on the flood depth. It depended on the water depth of the flood. This approach can be a guideline for designing flood disaster mitigation strategies, especially for the elements of residential areas.