A new planning model for canal scheduling of rotational irrigation

Water distribution systems often have multi-objectives such as equity, adequacy and timeliness. The canal systems distributing the water have different design capacities, command areas and lengths requiring different duration of operation. Irrigation scheduling under these conditions especially for rotational water distribution becomes a complex process. Optimisation techniques have limitations in the above situations either because of their pre-defined mathematical structure or because of the computational requirements to represent the reality. Hence, this study purports to develop a new multi-criteria approach for scheduling the rotational distribution system on a weight basis. Application of this model is demonstrated with an example of an irrigation system in India where rotational distribution is practised at distributary canal level. The results indicate that the performance of the water distribution system is better with the present model compared to the conventional scheduling procedure used. The concept can be extended to any level of rotational distribution, starting from main canal down to farm outlets.