Spatial Assessment of 2014-flood Disaster and Extent of Associated Damages in Lower Chenab Basin, Upper Indus Plain, Pakistan

Abstract

This study is an effort of spatial assessment of 2014-flood and associated damages in Upper Indus Plain (UIP). Community Based Disaster Risk Management (CBDRM) approach in integration to 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 30m spatial resolution and Landsat satellite image of September 2014 with same resoluation is acquired from open source geo-database of United States Geological Survey (USGS). Landsat satellite image is processes to extract the spatial extent of inundation. Watershed modelling approach is utilized to demarcate Chenab River Basin in GIS environment. Buffer analysis and Inverse Desistance 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 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 agricultural sector. Based on spatial extent, vertical profile and damages the study region is categorised 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.