Hydrological Characterization of Dholbaha Watershed in Shivalik Foothills using RS and GIS

Abstract

Hydrological characterization forms the basis of planning soil and water conservation treatments in a watershed. The morphometric analysis of Dholbaha watershed, in Shivalik foothills of Punjab was carried out using the IRS LISS-IV, Cartoset-1 merged satellite data, ASTER DEM and ArcGIS-9.3 software. Around 55% of watershed area had land slope higher than 10% with forest as major land use. The watershed was categorised as a 5th order watershed having 279 streams of length 191.73 km, out of which 213 were of 1st order. The drainage pattern was dendritic in nature with stream frequency of 4.67 no. km-2 and mean bifurcation ratio of 3.9. Both length as well as number of streams decreased with increase in the order of streams. Drainage density of 3.21 km.km-2 with fine drainage texture (7.34 no.km-1) and length of overland flow of 150 m in the watershed might result into high peaked hydrographs. The form factor, circularity ratio and elongation ratio indicated that the watershed was less elongated in shape, associated with medium to high relief, had moderately permeable sub-soil conditions generating moderate peak discharge and runoff volume resulting in high soil erosion necessitating urgent conservation measures to control siltation of the reservoir at the outlet of the watershed.