Irrigation Efficiency and Productivity Manual: Tools for Irrigation Professionals and Practitioners

Abstract

This manual is aiming to provide irrigation professionals in Tanzania and Eastern Africa two approaches for evaluating irrigation efficiency and productivity. These approaches are the traditional or conventional irrigation efficiency (CIE) methods and the irrigation situational efficiency (ISE). The ISE approach have been developed to address some of the important factors of measuring and assessing irrigation efficiency which cannot be addressed by the CIE. The manual is divided into four sections. Section one deal with evaluation of irrigation efficiency using the conventional or traditional methods. It also gives some key measurement parameters important for evaluating irrigation efficiency under this method and gives an example of the method for irrigation schemes based on design specification. Finally the section gives/outlines some important issues (demerits) which are not addressed in the CIE method. Section two is about the evaluation of irrigation efficiency and productivity using the ISE approach. It is important to note the inclusion of irrigation productivity as one of the important factor in the evaluation of efficiency under this methodology. Definitions, key measurement parameters and ISE indicators are dealt with giving examples from a case study drawn from Usangu Plains in Tanzania. Section three of the manual is about the determination of irrigation efficiency and productivity using the irrigation situational efficiency approach. Primary measurement of efficiency parameters and secondary indicators under ISE framework is clearly outlined and described in detail. Section four outlines some of the important aspects of improving irrigation efficiency and productivity in irrigation systems based on ISE evaluation. Potentials for water saving and intersectoral water allocations are also briefly discussed