Application of NRSC-SCS curve number model in runoff estimation using RS & GIS

This study aims to determine the runoff depth using NRCS-CN method with Remote sensing and Geographical Information System (GIS) and the effect of slope on runoff generation. This study was carried out in Bamhani catchment located in Mandla district of Madhya Pradesh. The USDA NRCS- CN method was applied for estimating the runoff depth in the Bamhani catchment. Soil map, Land Use and slope map were generated in GIS (Geographical Information System) Environment. The curve number method was followed to estimate runoff depth for selected storm events in the watershed. Effect of slope on CN values and runoff depth was determined. Statistically positive correlations were detected between between estimated and observed runoff depth is 0.77 and slope adjusted vs. observed runoff depth is 0.76. The result showed that the CN unadjusted value are lower in comparison to CN adjusted with slope. Remote sensing and GIS is very reliable technique for the preparation of most of the input data required by the SCS curve number model.