The effect of uncertainty in irrigation development

Uncertainty in irrigation development is of significant concern, more so nou than before, because marginal projects are being developed. Piecemeal efforts to account for uncertainty do not indicate its relative importance in design decisions; its only uhen uncertainty in all the input functions to the system is properly accounted for that its significance can be realised. This thesis presents a method of analysing an irrigation project in which uncertainty was directly taken into account. The design decision problem involved the choice of the capacity of an irrigation system using regulated streamflou. The analysis showed that the optimal size of the irrigation project and the expected utility value decreases as the level of uncertainty increases, and it also depends on the ability of the owners to survive poor harvests.Applied Science, Faculty ofCivil Engineering, Department ofGraduat