Irrigation is increasingly being called upon to help stabilize and grow food and water security in the face of multiple crises; these crises include climate change, but also recent global food and energy price crises, including the 2007/08 food and energy price crises, and the more recent crises triggered by the COVID 19 pandemic and the war on Ukraine. While irrigation development used to focus on public, large-scale, surface- and reservoir-fed systems, over the last several decades, private small-scale investments in groundwater irrigation have grown in importance and are expected to see rapid future growth, particularly in connection with solar-powered pumping systems. But is irrigation ‘fit-for-purpose’ to support population growth, economic development, and multiple food, energy and climate crises? This paper reviews how fit-for-purpose irrigation is with a focus on economies of scale of surface and groundwater systems, and a particular examination of systems in Sub-Saharan Africa where the need for expansion is largest. The review finds challenges for both larger surface and smaller groundwater systems in the face of growing demand for irrigated agriculture and dwindling and less reliable water supplies. To support resilience of the sector, we propose both a holistic design and management improvement agenda for larger surface systems, and a series of suggestions to improve sustainability concerns of groundwater systems

In the context of improving water productivity, there is a growing interest in deficit irrigation, an irrigation practice whereby water supply is reduced below maximum levels and mild stress is allowed with minimal effects on yield. Under conditions of scarce water supply and drought, deficit irrigation can lead to greater economic gains than maximizing yields per unit of water for a given crop; farmers are more inclined to use water more efficiently, and more water-efficient cash crop selection helps optimize returns. However, this approach requires precise knowledge of crop response to water as drought tolerance varies considerably by species, cultivar and stage of growth. The studies present the latest research concepts and involve various practices for deficit irrigation. Both annual and perennial crops were exposed to different levels of water stress, either during a particular growth phase, throughout the whole growing season or in a combination of growth stages. The overall finding, based on the synthesis of the different contributions, is that deficit or regulated-deficit irrigation can be beneficial where appropriately applied. Substantial savings of water can be achieved with little impact on the quality and quantity of the harvested yield. However, to be successful, an intimate knowledge of crop behavior is required, as crop response to water stress varies considerably.

This textbook focuses specifically on the combined topics of irrigation and drainage engineering. It emphasizes both basic concepts and practical applications of the latest technologies available. The design of irrigation, pumping, and drainage systems using Excel and Visual Basic for Applications programs are explained for both graduate and undergraduate students and practicing engineers. The book emphasizes environmental protection, economics, and engineering design processes. It includes detailed chapters on irrigation economics, soils, reference evapotranspiration, crop evapotranspiration, pipe flow, pumps, open-channel flow, groundwater, center pivots, turf and landscape, drip, orchards, wheel lines, hand lines, surfaces, greenhouse hydroponics, soil water movement, drainage systems design, drainage and wetlands contaminant fate and transport. It contains summaries, homework problems, and color photos. The book draws from the fields of fluid mechanics, soil physics, hydrology, soil chemistry, economics, and plant sciences to present a broad interdisciplinary view of the fundamental concepts in irrigation and drainage systems design.

This manual (most of whose modules were originally published 2001-2002) aims at strengthening various aspects of irrigation development, mainly emphasizing the engineering, agronomic and economic aspects of smallholder irrigation, in view of the limited practical references available in this area. It also introduces the irrigation practitioner to the social, health and environmental aspects, providing a bridge between the various disciplines involved in irrigation development.--Publisher's description.

First title in a major new seriesAddresses improving water productivity to relieve problems of scarcity and competition to provide for food and environmental securityDraws from scientists having a multitude of disciplines to approach this important problemIn a large number of developing countries, policy makers and researchers are increasingly aware of the conflicting demands on water, and look at agriculture to be more effective in its use of water. Focusing on both irrigated and rain-fed agriculture, this book gives a state of the art review of the limits and opportunities for improving water productivity in crop production. It demonstrates how efficiency of water use can be enhanced to maximize yields. The book represents the first in a new series of volumes resulting from the Comprehensive Assessment of Water Management in Agriculture, a research program conducted by the CGIAR's Future Harvest Centres, the Food and Agriculture Organization of the United Nations and partners worldwide. It will be of significant interest to those working in areas of soil and crop science, water management, irrigation, and development studies.

This book draws together the knowledge that has been gained in irrigation and drainage performance assessment over the last 10 to 15 yers. Performance assessment is an essential management task. If the use of water for irrigation is to be improved, then we must understand current levels of performance and identify measures for improvement. This book provides guidelines to enable practitioners to apply the process and procedures that have evolved. Developed by a working group of the International Commission on Irrigation and Drainage (ICID), it provides a theory and practice of how to audit and assess the performance of irrigation and drainage schemes. This book will be of interes to researchers and professionals in irrigation, drainage, soils and agricultural engineering.