People-centric geo-spatial exposure and damage assessment of 2014 flood in lower Chenab Basin, upper Indus Plain in Pakistan

This study is an effort of people-centric geo-spatial exposure and damage assessment of 2014-flood in Upper Indus Plain (UIP). Community-based disaster risk management (CBDRM) approach in integration with geo-spatial techniques is implemented to assess the nature and damages as well as community perception in reducing floods. In this regard, a semi-structured questionnaire was designed for micro-level detail investigation. A total of 422 households were surveyed in 22 flood-affected villages in eight districts forms the lower Chenab Basin using random sampling techniques. Secondary data regarding river discharge is collected from Regional Meteorological Centre, Lahore. Shuttle radar topographic mission (SRTM) Digital elevation model (DEM) having 30 m spatial resolution and Landsat satellite image of September 2014 with same resolution is acquired from open source geo-database of United States Geological Survey (USGS). Landsat satellite image is processed to extract the spatial extent of inundation. Watershed modeling approach is utilized to demarcate Chenab River Basin in a GIS environment. Buffer analysis and inverse distance weighted (IDW) technique of spatial interpolation are used to geo-visualize the spatial extent and depth of flood based on community perception. Analysis reveals that flood is one of the recurring phenomena in the Chenab Basin. The upper catchment areas of Chenab Basin are dominated by flash floods and low-lying areas are prone to riverine floods. The 2014-flood has caused estimated economic damage of 1409.295 million Pakistani Rupees (mPKR). Housing sector suffered the major losses of more than 1000mPKR followed by the agricultural sector. Based on spatial extent, vertical profile and damages the study region is categorized into upper and lower zones. The lower zone is most affected in terms of extent, depth and damages. This study can assist the decision-makers and disaster managers in designing location-specific flood risk reduction.