Optimal allocation of Short-Term Irrigation Supply

Abstract

An optimization model has been developed toaid decision making in real time fordeficit irrigation when conflict betweenwater supply and demand arises in amultiple crop irrigation scheme. The resultis the optimal allocation of short-termsupply of irrigation water. Theoptimization model is based on DynamicProgramming. In the optimization model, theshort-term supply is optimized in functionof a specified strategy determined by theuser. The strategies that the user canselect from are: maximum benefit, equitablebenefit, equitable yield and maintainingequity in the system. The potential of themodel has been assessed through applicationof the model to Perkerra irrigation schemein Kenya. In the 680 ha scheme, maize,onion and chili are cultivated in theirrigation season. Analysis of the resultsfor the 1999/2000 season, where the watersupply was 35 percent smaller than thedemand, indicates that improvements in cropproduction can be achieved throughapplication of the optimization model.Sensitivity of production system to variouslevels of water restriction is demonstratedby sensitivity analysisAn optimization model has been developed toaid decision making in real time fordeficit irrigation when conflict betweenwater supply and demand arises in amultiple crop irrigation scheme. The resultis the optimal allocation of short-termsupply of irrigation water. Theoptimization model is based on DynamicProgramming. In the optimization model, theshort-term supply is optimized in functionof a specified strategy determined by theuser. The strategies that the user canselect from are: maximum benefit, equitablebenefit, equitable yield and maintainingequity in the system. The potential of themodel has been assessed through applicationof the model to Perkerra irrigation schemein Kenya. In the 680 ha scheme, maize,onion and chili are cultivated in theirrigation season. Analysis of the resultsfor the 1999/2000 season, where the watersupply was 35 percent smaller than thedemand, indicates that improvements in cropproduction can be achieved throughapplication of the optimization model.Sensitivity of production system to variouslevels of water restriction is demonstratedby sensitivity analysis.