IDENTIFYING RUNOFF HARVESTING SITES OVER THE PENNAR BASIN, ANDHRAPRADESH USING SCS-CN METHOD

In this study, potential runoff generating sites, and thus priority areas for runoff harvesting, over Pennar Basin, Andhrapradesh, India are identified with the use of RS and GIS. Adopted criteria for selecting potential runoff generating sites, and thus priority areas are watershed characteristics, soil suitability, slope suitability, land use, and harvesting potential for the upstream catchment. The potential runoff generating sites for a given rainfall event over the basin are identified using SCS Curve Number. Output of this study, is presented using ‘suitability maps'. The ‘suitability maps' for locating priority sites for runoff harvesting, helps to reduce the extent of the area to be investigated for effective runoff harvesting, by identifying specific areas that are potential sites for runoff harvesting, and which can then be verified in the field. Providing an accurate spatial representation of the runoff generation potential within a watershed is an important factor in developing a strategic runoff harvesting plan for any water scarce rural watershed. The use of GIS approach to facilitate this process improves the accuracy level for locating suitable areas for runoff harvesting in view of the GIS capability to utilize spatial information in an integrative manner and spatially displaying it through maps.