A flood risk assessment based on an OpenStreetMap application: a case study in Manmunai North Divisional Secretariat of Batticaloa, Sri Lanka (original) (raw)

In the recent past, Sri Lanka has been experiencing an increase of intensity and frequency of natural disasters. Therefore, the study was carried out to introduce an Open Source application to collect the field level information and to identify the flood inundation areas through a 3D model. The case study area included 48 Grama Niladhari Divisions in Manmunai North Divisional Secretariat (DS), Batticaloa District, Sri Lanka. The study helped to analyze the role of OpenStreetMap (OSM) to support the mapping of the flood risk level of the study area. This objective was achieved by collecting flood exposure data through community participatory method using OSM, which was integrated into a Digital Elevation Model (DEM). Elevation points were collected using Google Earth and TCX Converter. The flood hazard maps were created using inputs such as water depth and flood extent of the DEM and verified through a local community participatory mapping exercise. Next, vulnerability maps were gene...