Analysis of Drainage Morphometry and Watershed Prioritization of Romushi - Sasar Catchment, Kashmir Valley, India using Remote Sensing and GIS Technology

The application of remote sensing and geographical information system for the analysis of morphometric parameters are found to be of immense utility in watershed prioritization for soil, water conservation and natural resources management at micro level. This study is an attempt to carry out detailed investigation of linear, shape and relief morphometric parameters like stream length, stream order, drainage density, stream frequency, bifurcation ratio, Length of overland flow, basin perimeter, form factor, compactness coefficient, elongation ratio, basin relief, ruggedness ratio, shape factor and texture ratio in five micro-watersheds of Romushi-Sasar Catchment and their prioritization. For the study area, stream network along with their order was extracted from survey of India toposheets 1961 (1: 50,000 scale) and ASTER DEM 30m in GIS (geospatial) environment and stream order up to 6 has been examined. Based on morphometric analysis and the ranking of each parameter, the sub-watersheds have been classified into three categories high, medium and low in terms of priority for conservation and management of resources. The results reveal that RSMW4 and RSMW5 watershed falls under very high priority and emphasized that prioritization of smaller hydrological unit’s i.e. micro-watersheds is ideally recommended for initiating soil and water conservation measures in a watershed. These high priority sub-watersheds have highest bifurcation ratio, high altitudinal, high slope and deep valley topography which indicate strong structural control on the drainage and are accordingly more prone to natural disasters because presence of structures in hard rock acting as weak planes and openings for seepage of water that enhance chances of landsliding. The sub-watershed RSMW4 and RSMW5 has lowest compound parameter value of 2.22, 2.44 and are likely to be subjected to maximum soil erosion. Hence theses should be provided with immediate soil conservation measures.