TR-99 : Geomorphology of Kolar sub basin for hydrological studies

Abstract

The hydrologic response of a watershed usually depends upon the climatological and watershed characteristics. The geomorphological characteristics of a watershed represent the attributes of the watershed that can be employed in synthesizing, and perhaps understanding its hydrologic behaviour. For the purpose of -hydrological studies, geomorphological characteristics can generally be classified in three groups;(i) the characteristics representing the linear aspects of the watershed, (ii) the characteristics which represent the areal aspects of the watershed, and (iii) the characteristics representing the relief aspects of the watershed.

In this report a comprehensive review of the geomorphological properties, covering the linear, areal and relief aspects of the watershed are presented. Methodology for the estimation of some of the important geomorphological parameters are also described. Based on the given methodology a computer software has been developed in FORTRAN-77 language. It requires the digitized data of the drainage network as input. The developed computer software has been implemented and tested on VAX 11/780 computer system available at NIH. The different geomorphological characteristics of Kolar sub basin of Narmada basin are derived using the developed software. Further a review of the application of geomorphological properties in various hydrological studies such as Empirical Formulae, Regional Flood Frequency Analysis, Regional Unit Hydrograph and Geomorphological Unit Hydrograph etc., are also presented in the report. It is observed from the review of various hydrological studies that the different geomorphological parameters derived for Kolar sub basin can be utilized for modelling its hydrologic response. Such applications are generally found to be more useful specifically for the ungauged catchments or catchments having the limited data in simulating their hydrologic response.