Managing canal water through farm-pond fed pressurized irrigation system

Abstract

The hydraulic performance of Nagpur minor canal system under Puri main canal jurisdiction (Odisha) having adequacy, equity and relative water supply values of 0.3, 0.68 and 0.72, respectively revealed the reduced performance of the system. Thus, in order to increase its performance in the command in terms of yield enhancement of crops, less water use and increase in physical as well as economic water productivity, pipe based pressurized irrigation system connected with farm ponds were laid out in upper, middle and lower canal reaches. Crops like groundnut, sesamum and vegetables were promoted during post-monsoon season in the year 2017-18 and 2018-19. In head reach, the crop yield and physical water productivity of groundnut and sesamum crops increased in the range of 14.5-28.9% and 41-75.5%, respectively, using 18.2-24.2% less water under pipe conveyance system, when compared with channel conveyance system. In middle reach, for the same crops, the performance of the sprinkler irrigation system was compared with pipe conveyance based irrigation and channel irrigation. There was increase in yield by 18.9% and 35.3% in groundnut, and 19.8% and 35.9% in sesamum under sprinkler irrigation system in comparison with pipe conveyance and channel conveyance systems, respectively. Physical water productivity through sprinkler irrigation system resulted 0.88 kg m-3 and 1.18 kg m-3 for groundnut and sesamum, respectively. Similarly, in lower reach, while growing groundnut, pointed gourd and bitter gourd, the yield increased by 28.4% and 39.5%; 25.1% and 33.0%; and 23.4% and 30.3% under drip irrigation system when compared with pipe conveyance and channel conveyance systems, respectively. The physical water productivity was observed as 8.48 kg m-3 and 9.85 kg m-3 in case of bitter gourd and pointed gourd through drip irrigation system, respectively. Further, drip irrigation system resulted in net economic water productivity of 111.5 ` m-3, whereas channel conveyance system reported 117.6% less net economic water productivity. Thus, the provision of pressurized irrigation system in canal command area promises an opportunity for enhancing physical as well as economic water productivity.