Ecology, Environment and Conservation Paper

APPRAISAL OF ON-FARM WATER DISTRIBUTION IN LATERAL COMMANDS OF UPPER KRISHNA PROJECT, KARNATAKA

N.K. Rajeshkumar, P. Balakrishnan, U. Satishkumar, B.S. Polisgowdar, B.K. Desai and H. Lokesha

Abstract

Post-independence development of irrigation in India was phenomenal, which greatly contributed for ‘green revolution’ and achieving food production targets. However, poor operating efficiencies of irrigation projects due to unscientific management of land and water resources and inappropriate cropping pattern in the command areas have posed serious concern. This has led to excess irrigation application, conveyance losses and wastage of water through outlets with low crop yields. The financial returns were not commensurate with the investments made in irrigation sector and there were also problems of waterlogging and salinity. Keeping these aspects in view, a study was carried out on evaluation of land, water and cropping practices in different reaches of command areas of two selected laterals of the Upper Krishna Project (UKP), Karnataka during 2012-’14. The results revealed that cropping intensity in both the laterals was more in kharif season (73.25- 99.97 per cent) compared to rabi season (15.94-75.13 per cent). Paddy area was pre-dominant, though it was not at all considered in the originally envisaged cropping pattern. There were excess inflows at the lateral heads than actually required, ranging from 27.94-51.76 per cent and 42.49-56.44 per cent with water demand-delivery ratios of 0.48-0.72 and 0.44-0.58 in kharif and rabi seasons respectively. Similarly, the excess irrigation application than required at field level varied from 21.11-27.98 per cent and from 21.03-30.54 per cent during kharif and rabi respectively. The conveyance and outlet losses observed ranged from 16.17-16.99 per cent and 6.83- 26.79 per cent in kharif and from 16.58-19.88 per cent and 19.40- 35.41 per cent in rabi respectively. Further, excess amounts of water applied more than the requirements to paddy, cotton, pigeonpea and chilli varied from 22.03-26.05, 18.16-22.69, 16.21-19.85, 15.67- 21.76 per cent for during kharif and from 18.71-25.07, 10.45-21.59, 14.79-17.42 and 10.76-21.87 per cent during rabi respectively. All the above losses were quite considerable and if they were minimised and put to efficient use, additionally 4.88-62.90 ha in kharif and 10.34- 69.18 ha in rabi season could have been cropped with high to light irrigated crops, which in turn would have fetched higher farm returns. Moreover, as the water table is shallow in some pockets of the lower reaches of the command area, canal water releases need to be regulated in conjunction with groundwater and adopting appropriate cropping pattern in different reaches of command areas. This would minimise the problems of water shortage in the tail-end areas, thereby would help in sustainability of irrigated agriculture.