Morphometric Analysis of the Tunga River Sub-catchment, Karnataka, India Using Remote Sensing and QGIS: Implications on Water Resource Allocation

Tunga River Sub-catchment is situated in Western Ghats, Karnataka and has a humid climate. The qualitative morphometric analysis is significant to gauge the basin potential is essential for management of natural resource under increasing precipitation trends. Linear, areal and relief aspects are computed and evaluated using Quantum Geographical Information System (QGIS 3.28) plugins. Drainage network derived SRTM DEM 30m indicates Tunga River Sub-catchment is a 5th Order basin with sub-dendritic drainage network. Areal features such as Elongation ratio (0.51), Circularity ratio (0.31) and Form factor (0.20) indicates the basin is elongated and the time of concentration for present study is 12.23 hours. Low Drainage density (0.61 km/km2) indicates that the basin is composed of permeable material having low to moderate relief. Low Infiltration number (0.15), high Length of overland flow (0.81) and high Constant of channel maintenance (1.62), indicate that there may be more opportunities for infiltration, potentially leading to higher groundwater recharge rates. Sub-catchment potential assessment using aspects such as Stream frequency and Drainage density in relationship between Bifurcation ratio ensures the catchment has high basin potential.