Land Resource and Hydrological Inventory of Chik Hangargi Sub-watershed for Watershed Planning and Development Jewargi Taluk, Kalaburagi District, Karnataka (AESR 6.2)

Abstract

The average annual rainfall of 786 mm in the Chik Hangargi sub-watershed as recorded from the Yedrami station data by KSNDMC. 77%, 14% and 9% 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 in deficit .The cropping & irrigation choices are not appropriate and need to be altered to shift the deficit water balance. The estimated runoff available to use is 25 mm for an average annual rainfall of 584 mm (2009-2017). The utilizable groundwater is 38.5 mm (70% of 55 mm recharge estimated). This means the total available water resource combining the soil moisture store for kharif & rabi (219 mm) and utilizable runoff plus recharge is 282 (=219+25+38.5) The average actual evapotranspiration estimated in the watershed based on the current land use and irrigation practices for the kharif and rabi seasons is 534 mm. Hence the amount of water use for kharif and rabi seasons may be estimated as 667 mm (i.e 125% of AET). This demand for the two seasons is higher by 385 mm, i.e. (667-282). The AET in June-Sept months is 77% of rainfall. Hence, there is a good opportunity to harvest the excess water through watershed management practices for utilizing during rabi season. The total number of wells present in Chik Hangargi Sub-watershed as per LRI data is 4 (Open wells). The groundwater level was found from the data obtained from KSNDMC for the nearest station Yedrami . Deepest levels were found in 2016.