Morphometric analysis of the Jalleru Vagu sub-basin of Yerrakalva River, Eluru district, Andhra Pradesh (India), using geo-spatial technology

Morphometric analysis is a valuable approach for studying groundwater reservoirs by systematically evaluating the diverse topographical features and intricate drainage networks within a specific basin. In this study, we categorized the extracted drainage framework using Strahler's scheme, revealing a dendritic to sub-dendritic drainage pattern within the 312 km(2) Jalleru vagu sub-basin, which is an integral part of the Yerrakaluva River system. High- resolution satellite imagery IRS Sat-2- LISS IV, P - 102 / R- 60, 61 acquired from 20th March, 2023 was used to analyze linear, areal, and relief aspects. The Jalleru vagu sub-basin, which is a fifth-order basin, is primarily characterized by lower-order streams, with a mean drainage density of 1.17 km/km2. The highest slope in the basin is 590 m, primarily due to regional geology and cycles of erosion. The basin is elongated, with steep inclines, and modest elevation variations (elongation ratio: 0.30). A high drainage texture value increases the risk of soil erosion, which according to the drainage texture analysis, comes to 4.15. The study demarcates low to medium flood and erosion prone zones, Overall, the study area is elongated with less structural control and low to medium flood and erosional potentials. However, owing to low to medium flood and erosional susceptibility, and high groundwater withdrawals, water harvesting structures like check dams, levees, percolation tanks, rock dam are recommended for replenishment of groundwater resources.