Flood Forecasting of an Ungauged Trans-boundary Chenab River Basin Using Distributed Hydrological Model Integrated Flood Analysis System (IFAS)

Abstract

River Chenab at rim station Marala covers 97 % of its catchment in India while the only 3 % inPakistan. The trans-boundary basin is ungauged and during the real time flood and it is difficult to collect the information from India hence used satellite rainfall data for flood prediction. Three different flood events have been studied to make the IFAS model applicable for the flood forecasting of Chenab River so that the losses and damages due to flooding could be minimized. The results of Tuned IFAS (Peak discharge error= 7 %, wave shape error= 29.5 %, volume error= 8.5 %) are much better as compared to IFAS with default parameters (Peak discharge error= 82 %, wave shape error= 15.7 %, volume error= 53 %). The Satellite rainfall data namely Global Satellite Mapping of Precipitation GSMaP_NRT (Near Real Time) has been used by hydrological model Integrate Flood Analysis System (IFAS) for rainfall runoff modeling. The results of Satellite GSMaP_NRT with tuned parameters showed good agreement with the observed discharge values at the ground measuring station. The Satellite GSMaP_NRT captured flood duration and flood peak with reliable accuracy. The IFAS showed the capability to generate sufficient lead time flood forecast for the local downstream population. This tuned IFAS model is practically helpful for the flood early warning and to save the lives and movable properties of the downstream local communities.