The effects of irrigation on poverty: a framework for analysis

Irrigation projects have been the subject of much bad press coverage because of the sometimes very damaging environmental and social impacts associated with large-scale projects such as dams, declining aid to agriculture and falling rates of economic returns to irrigation since the heyday of the 1970s. Yet irrigation remains one of the most crucial inputs into farming and therefore a potentially important poverty reduction tool for the 21st century. We review some of the evidence surrounding trends in investments in irrigation and the reasons behind the decline. We also provide a framework for analysing the positive and negative impacts of irrigation on poverty, how these might differ by the type of irrigation technology and review some of the evidence of these impacts. We reach a number of conclusions about the conditions under which irrigation is most likely to have a positive impact on the poor, but we also report that the evidence is patchy, and usually not gathered in such a way as to allow easy conclusions to be drawn.