Development and Evaluation of a Near Real Time System for Assessing Hydrologic Response in Chenab River Catchment

Abstract

Investigating the hydrologic response of a catchment to adverse climate changes is crucial for managing land and water resources and mitigating the natural hazards like floods. Limited availability of the in situ data, especially in case of transboundary rivers, fur- ther highlights the need to develop and evaluate decision support systems which may predict the flows in near real time using open source satellite rainfall data. Study was conducted in the Chenab river catchment to develop and evaluate a hydrologic model using HEC-HMS for predicting flows based on TRMM rainfall data. The catchment was analyzed regarding hydro- morphological properties using HEC-GeoHMS tools. Digital soil map of the world developed by FAO and global land cover map developed by European Space Agency were utilized to develop Curve Numbers for the sub-basins. The model was calibrated and validated for summer/rainy months (June-September) for 2006 and 2007, respectively. There was found consistency between simulated and observed flows with percent difference in volume to be 5.49% and 6.61% for calibration and validation periods, respectively. Values of Nash- Sutcliffe Efficiency were found relatively less (0.57 for calibration and 0.07 for validation) possibly due to continuous nature of simulations. Further refinement in calibrated parameters can be performed based on event-based simulations to better capture the effects of extreme rainfall events in terms of floods, and all this analysis may help as a mile stone in developing a near real time decision support system.