Water does not respect geopolitical boundaries. Hydrological systems are completely oblivious of international relations. This makes life complicated for the water managers, financiers, diplomats, and most of all – the water users – around the world’s approximately 276 transboundary river basins, 63 of which are in Africa. Sixty percent of the world’s freshwater flows are in transboundary rivers, and 40% of the world’s population lives in their river basins. When water cuts across borders, it poses economic, financial, logistical and political challenges for people trying to manage and develop the resource.
Climate change is increasing uncertainty about where and when water will be available. It is affecting billions of people living in transboundary basins, and as often happens, the poor are the hardest hit. There is a long list of potential problems people will face – supply in water-stressed regions will diminish; some regions are likely to have more water than they can handle; most challenging is the fact that the timing and amounts of future water availability are impossible to predict with certainty. Other risks - the increasing intensity of droughts, floods, typhoons, and monsoons; uncertainties around waterborne disease; glacier melt and decreased storage in snow-pack; glacial-lake outburst floods; sea-level rise and salt-water intrusion - all pose the highest risk to poor communities that are least able to cope.