Least-Cost Planning of Irrigation Systems

A mixed-integer programming model was used to obtain least-cost system rehabilitation plans for a 6,900-ha (17,000-acre) irrigation project in southeastern Idaho. Three types of gravity conveyance system components (existing unlined canal, concrete lined canal, and gravity pipe) were considered, along with five types of irrigation application systems (two gravity and three sprinkler application systems). The mixed-integer programming model that complied with the constraints specified was flexible and effective. The specified constraints used in this study are water charges and water and land availabilities. The quantitative effects of different constraints were easily evaluated. The same modeling procedure can also be used in developing scenarios of alternative system configurations for a new irrigation project development for leastcost system planning. The model gives descriptive scenarios that can assist planners, irrigators, and other interested parties in making multiple-objective planning decisions for developing or rehabilitating irrigation projects.