Application of SCS model with GIS data base for estimation of runoff in an arid watershed

摘要

Soil Conservation Service (SCS) model has been applied in the present study for the estimation of runoff from an arid watershed. The watershed, comprising about 509 ha, is a part of upper Jojri basin extends from 26 deg 32 min to 26 deg 35 min N and73 deg 47 min to 73 deg 50 min E in Nagaur district of Rajasthan. This method involves various types of information related to topography and soil. The thematic maps viz. soil, land use/cover have been prepared by interpretation of satellite data (IRS -1C) and topographical maps obtained from Survey of India. All this information was converted into raster format at a scale 1:50,000 and used as input to derive the modified Soil Conservation Service (SCS) runoff curve number. The SCS model was then applied to estimate the runoff for daily storm and was validated comparing it with the measured runoff of five events of present monsoon period, year 2000.