Prediction of Continuous Rainfall-Runoff Scenarios for Snow-Fed Watershed of Himachal Pradesh, India using Geographical Information System GIS based on Hydrological Modelling

Abstract

Rainfall runoff modeling is one of the most complex hydrological modeling due to the involvement of different watershed physical parameters. It is essential for the analysis of watershed hydrological response towards the received precipitation under the influence of watershed variables. As it is a replica of watershed hydrological response, Rainfall-Runoff modeling is essential to evaluate the general characteristics of total surface runoff at catchment’s outlet. The main objective of this study was prediction of rainfall runoff using Hydrologic Engineering Center-Hydrologic Modeling System [HEC-HMS] model for Rampur watershed which was covered in Kullu and Shimla districts situated at Upper Sutlej sub-basin of Himachal Pradesh, India. Geo-spatial data of Digital Elevation Model,LandUse-LandCover (LU-LC) map, Soil map and Hydro-meteorological data of rainfall were collected from different open source web portals to utilise as input parameters for modeling. Soil Conservation Service-Curve Number (SCS-CN) for precipitation loss modeling, Soil Conservation Service–Dimensionless Unit Hydrograph [SCS-UH] for transform modeling, Muskingum method for Runoff routing were used as input parameters of respective components of HEC-HMS model. This article proposes a methodology for generating hourly rainfall data from daily rainfall data using Intensity-Duration-Frequencycurves in Meteorological model of HMS. The simulation results of runoff with 5 different return period scenarios are follows the return period frequency tendency, such as 1000 year return period runoff peak delivers 4729.5 m3/s, 500 year return period delivers a peak runoff of 4263.9 m3/s, 100 year return period gives a peak runoff of 3196.5 m3/s, 50 year return period runoff deliver 2745.3 m3/s and 10 year return period deliver 953.7 m3/s runoff at the outlet of Rampur watershed.