Morphometric analysis of Andhale watershed, Taluka Mulshi, District Pune, India

Bhavana N. Umrikar

doi:10.1007/s13201-016-0390-7

Abstract

The morphometric analysis coupled with remote sensing and geographical information system techniques evaluates various valuable parameters for the watershed development plan of drought-prone Andhale watershed of Pune district, Maharashtra. The upper part of the watershed shows parallel–sub parallel and rectilinear drainage patterns indicative of structural control, whereas the lower part shows dendritic drainage pattern revealing the homogeneity in texture and lack of structural control. The elongated shape of this basin is indicated by values of form factor, circulatory ratio and elongation ratio. The mean bifurcation ratio is observed to be 4.65 indicating the watershed is less affected by structural disturbances, and drainage pattern is not much influenced by geological structures. The hypsometric integral obtained for Andhale watershed is 0.316 indicating maturity stage of the basin. The longitudinal profile depicts steep gradient at the origin but it gradually flattens out as the river erodes its base level. The high values of drainage density, stream frequency, infiltration number and drainage texture indicate that the study area is underlain by impermeable rocks responsible for high runoff. Thus, the results of this analysis would be useful in determining the effect of catchment characteristics such as size, shape, slope of the catchment on runoff vis-a-vis the scope for water harvesting.

Highlights

Watershed development and management programmes in hard rock terrain play a key role in establishing the demand and supply side equilibrium
Morphometric analysis of a drainage basin is a quantitative way of describing the characteristics of the surface form of a drainage pattern and provides important information about the region’s topography, geological structures, runoff and hydrogeological properties of underlying rock
The drainage density values reveal that the nature of sub-surface strata is impermeable where the drainage density values are greater than five

Summary

Introduction

Watershed development and management programmes in hard rock terrain play a key role in establishing the demand and supply side equilibrium. The study area is characterized by monsoon climate (Indian Meteorology Department 1982) It receives rainfall from the SW monsoon. The study area is drained by river Andhale that is the fifthorder stream. The streams in this area are sparsely distributed compared with lower reaches of the watershed. (b) Rectilinear type the drainage indicative of the structural control observe towards the north east part of the watershed. This pattern is found in the higher order streams of the Andhale watershed revealing the homogeneity in texture and lack of structural control. The specific rock types exposed in the area show a variety of basalts viz. Compact Basalt, Vesicular Basalt, Amygdaloidal Basalt or composite of both Vesicular–Amygdaloidal Basalt (Fig. 3)

Methodology

Findings

Discussion and conclusion