SWAT MODELLING FOR SEDIMENT YIELD: A CASE STUDY OF UJJANI RESERVOIR IN MAHARASHTRA, INDIA

This study is related to the use of SWAT model for the prediction of sediment yield from the rainwater runoff in the Upper Bhima Basin (UBB) which is the source of water for the terminal reservoir called Ujjani Reservoir, in Solapur district, Maharashtra State, in India. SWAT-model configuration was developed, using data pertaining to 27 sub-basins in the catchment area of the UBB. Extensive use of satellite images has been done, for a period of 2 years and 7 months (January 2012 to July 2014). Digital Elevation Model (DEM), Land Use and Soil data were included, in addition to climatic data applicable to the area. The annual average sediment yield in the various reaches of sub-basins was estimated to vary from 1342.0 tons/year to 888010.0 tons/year, during the study period. The trend of results the SWAT model applied to Ujjani Reservoir will serve as a clue to similar studies in major reservoirs in India, in estimating the sediment yield from the rainwater surface runoff. These estimates have relevance to soil conservation schemes envisioned in the catchment areas, and for ensuring adequate water storage needed for meeting the requirements of the various human uses. Also, the sediments yielded to Ujjani Reservoir could be thought of as a resource for sand, a building material which is very much in demand, as reported by Bhamre,P.R., et.al (2014), if the sediments could be harvested, annually, by suitable de-silting/dredging operations.