FLOOD HAZARD MODELLING USING HYDRAULIC SIMULATION MODEL AND SATELLITE IMAGES: A CASE STUDY OF CHAJ DOAB, PUNJAB, PAKISTAN

Abstract

The main objective of the study is to determine the highly risked areas and to estimate flood extend through different return periods. HecGeo-RAS is used along with Hydrologic Engineering Center River Analysis System (HEC-RAS) to build a model which have analyzed the flow of water. The river and floodplain geometry were obtained by SRTM-DEM and flood mapping is finalized by the vector layer analysis in ARC GIS. Frequency analysis for the period 1986-2014 (29 years), instantaneous discharge data performed by Gumbel's, and LP3. Results depicts that District Mandibahudin always flooded on both sides by Jehlum and Chenab rivers. An interpretation of findings explicitly revealed that the 50-year return cycle flood at Trimmu (5299 m 3 s-1) would inundate 500 percent more area than the natural surge. Urban areas are also vulnerable to flooding such as Mandibahudin, which were also evident in the July / August 2014 flooding.