ABSTRACT
This chapter describes five important features of groundwater: flow process within hard rock and alluvial aquifers, water losses in irrigation schemes, the estimation of the recharge entering the aquifer systems, artificial or enhanced recharge, and finally the exploitation of aquifers of limited saturated thickness. For each issue, fieldwork is the first essential step followed by the development of a conceptual understanding; this can lead to computational modeling. The chapter explores the reasons for their success, especially when power for operating the pump is only available for a limited time period, and also when irrigation occurs for only a few hours. During the 1980s, several investigations were carried out to understand the flow processes in hard rock and alluvial aquifers. These investigations were based on careful fieldwork and the formulation of conceptual models, followed by the construction of computational models to confirm and quantify the conceptual understanding.
