Morphometric Analysis using GIS in Pambar Sub Basin, Krishnagiri and Vellore District, Tamilnadu, India

Abstract

The study area taken is Pambar Sub-basin, covered in two districts such as Krishnagiri district and Vellore district of Tamil Nadu. It lies between the latitudes 12°10' - 12°45' and longitudes 78°15' - 78°50' of Toposheets No. 57 L/6, 57 L/7, 57 L/10, 57 L/11, 57 L/12, 57 L/14 and 57 L/15 of scale 1:50,000 published by Survey of India in 1973. Pambar basin covers total area of about 1735 SqKm. A detailed hydrogeological investigation of river basin needs a thorough understanding of the drainage basin morphology which enlight on Lithology, Structural controls, Relative runoff, Recharge, Erosional aspects and stage of development of a basin. Ever since 1895 morphometric analysis of a drainage basin has attracted more attention and it is still being apply for drawing subtle conclusions regarding nature, behaviour of geomorphology and water resources evaluation and managements. In this study an attempt has been made to understanding the various morphometric parameters in the Pambar watershed. The simpler unambiguous system of stream ordering proposed by Strahelr's has been followed which provide the mean of measuring size and form properties of watershed. In the present study, morphometric analysis of the Manas drainage basin has been carried using earth observation data and geographical information system (GIS) techniques. The morphometric parameters considered for analysis includes the linear, areal and relief aspects of the basin. frequency, Form factor, Elevation difference, Basin perimeter, Basin circularity, Drainage density and Ruggedness number were calculated and discussed salient features. Altogether sixteen parameters were computed for all the sub basins in ArcGIS environment. Drainage lines were classified under Strahler's scheme ordering system. Surface water resources could be enhanced in the region by constructing check dams and creating artificial recharge through effective planning and management.