Sediment Yield Modeling of A Watershed Using GIS

Abstract

The study watershed, Wadsa-Chincholi is a part of Godavari river basin and its total area is 14,690 km2. In this study, Wadsa-Chincholi watershed was divided into 200 m × 200 m grid cell and the average annual sediment yield was estimated at the outlet of watershed using Morgan-Morgan and Finney (MMF) model and the Universal Soil Loss Equation (USLE). Geographic Information System (GIS) was used as a tool to generate, manipulate and spatially organize disparate data for sediment yield modeling. Based on eight years daily rainfall data, the estimated maximum and minimum values of kinetic energy were found to be 47452.82 and 25298.86 J m-2 for year 2007and 2004 respectively. The Shuttle Radar Topography Mission (SRTM) data was used to generate slope and drainage map of the study watershed. Further, the sediment yields estimated by both the models were compared with observed data. The estimated average annual sediment yield from MMF and USLE model were found to be 11.17 t.ha-1yr-1 and 3.67 t.ha-1yr-1, respectively. The average annual sediment yield obtained from the USLE model is closely matching with the observed values. Hence, the results of the USLE model can be applied for spatial sediment yield estimation of the Wadsa-Chincholi watershed.