A Rationale for Furrow Irrigation System Design and Management

• Main Author: Hamad, Safa Noori
• Format: Others
• Published: DigitalCommons@USU 1976
• Subjects: Engineering
• Online Access: https://digitalcommons.usu.edu/etd/6459; https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=7643&context=etd

Mathematical and computerized models are developed to design and optimize furrow irrigation systems. The optimization process starts with land grading design, if any is needed, followed by a prediction of maximum non-erosive furrow stream size allowed on a given soil and the associated furrow-advance function. An average depth of application per irrigation is then assumed from which the wetting pattern along the furrow and the amounts of runoff water are predicted. A design of an Irrigation Runoff Recovery System, IRRS, is then executed, if desired, and system cost is determined. Using the predicted wetting pattern and the appropriate Crop Production Function, the gross return and the net farm profit associated with that particular average depth of application per irrigation are determined . The iterative procedure is continued by changing the average depth of application per irrigation and evaluating net farm profit until a depth and the associated system design and management program which yield the highest net profit are found. A Fortran IV detailed computer program is developed to perform the above procedure. The program is comprehensive and very flexible so that it can be used both for research and practical design purposes and can accommodate further improvements and expansion. The results of sensitivity analysis conducted to study the effect on net farm profit of ten major design and management factors are included. Numerous conclusions, suggestions, and recommendations to improve furrow irrigation system design and operation are presented.