The challenges of water scarcity and climate change require those countries located in arid regions to adapt and develop long-term solutions. This is certainly the case for Namibia, which is the most arid African country south of the Sahara. The majority (60-70%) of Namibia's population depends on subsistence agriculture, practised on non-freehold or communal land under conditions of low and highly variable (spatially, temporally) annual rainfall. Increasing population and unemployment combine to create a strong direct dependency on natural resources and a related increasing demand for land and access to water (Werner, 2007). This is occurring under prevailing conditions of overgrazing and declining water tables, which require policy and management interventions (MET, 2005) that are also robust in terms of responding to the uncertainties of climate change. The situation just described is most pronounced in the densely populated central parts of northern Namibia, which is the geographical focus of this study (see Figure 1). The region1 covers four administrative areas - Omusati, Oshana, Ohangwena and Oshikoto - and is inhabited by almost half of the Namibian population. It is characterized by unreliable rainfall, mostly brackish or saline groundwater and an absence of perennial rivers. Presently, most drinking water is abstracted from the Calueque Dam - near Ruacana on the Kunene River - which is shared between Angola and Namibia. The water is transported to end users through an open canal (150 km) supplying a system of pipelines measuring some 2 000 km. The raw water is treated for drinking water purposes, but is also supplied for other purposes such as stock-watering (Niemann, 2000).