Optimal Crop Planning for Retamunda Branch Canal System under Uncertainty of Canal Release

Abstract

Improvement of water productivity of the canal commands through structural interventions requires huge investment. This paper describes nonstructural interventions through development of optimal crop planning in the Retamunda Branch Canal System, a tail end branch canal of the Hirakud Command, in the western part of Odisha. Considering four scenarios with different objectives, the optimal cropping patterns under the commands of individual distributaries have been worked out, using linear programming, so that improvement in irrigation efficiency, in terms of water productivity, could be feasible. Among various scenarios, the cropping pattern obtained under Scenario – II, with the objective to utilize the maximum area for cultivation along with the constraint of water availability for each outlet was found to be feasible for optimal land and water utilization and generation of requisite employment. The optimal cropping pattern due to uncertainty of water availability for irrigation was analyzed at 90%, 75% and 60% of the present release. It was observed that with the decrease in canal release up to 10%, 25% and 40%, it is possible to obtain about 97%, 93% and 87% of the net return per unit area that is obtained with 100% of canal release under Scenario – II. However, it is not feasible to plan at least 1/3rd of the command area under heavy duty crops with the decrease in canal release beyond 10%.