Land Resource and Hydrological Inventory of Murlapura Sub-watershed for Watershed Planning and Development Koppal Taluk, Koppal District, Karnataka (AESR 3.0)

Abstract

The average annual rainfall of 631 mm in the Murlapura sub-watershed as recorded from the Alavandi station data by KSNDMC. 60%,21% and 19% of the annual rainfall occurs during kharif, rabi and summer seasons respectively and exhibited a higher temporal variability. The evapotranspiration estimation tool developed indicates that the watershed water balance is sustainable. The cropping & irrigation choices are appropriate and need not be altered. The estimated runoff available to use is 3 mm for an average annual rainfall of 584 mm (2009-2017). The utilizable groundwater is 31 mm (70% of 44 mm recharge estimated). This means the total available water resource combining the soil moisture store for kharif & rabi (192 mm) and utilizable runoff plus recharge is 226 (=192+31+3) The average actual evapotranspiration estimated in the watershed based on the current land use and irrigation practices for the kharif and rabi seasons is 494 mm. Hence the amount of water use for kharif and rabi seasons may be estimated as 617 mm (i.e 125% of AET). This demand for the two seasons is higher by 391 mm, i.e. (617-226). The AET in June-Sept months is more than rainfall. The total number of wells present in Murlapura Sub-watershed as per LRI data are 37 (Bore wells). The groundwater level was found from the data obtained from KSNDMC for the nearest station Bardur