The supply of safe drinking water, protection against floods and droughts, and the resolution of conflicts between competing water users in the case of resource scarcity, are among the main aims of development co-operation in the water sector. The impacts of climate change will make it even more challenging to achieve these objectives in many world regions, by putting additional pressures on water resources. This desk study for the German development co-operation (GTZ) evaluates scientific evidence for climate change impacts and potential options for adaptation in water management in Africa, and derives recommendations for meeting these challenges.

Climate change will exacerbate existing water shortages, impair water quality or increase the frequency, duration and intensity of floods and droughts in many regions in Africa and world-wide. Rising sea levels and the resulting increase in storm surges threaten cities and settlements in coastal regions.

Developing countries are characterised by a particularly high vulnerability vis-à-vis the water-related climate change impacts, firstly because these impacts will often be particularly severe, and secondly because in many cases the necessary institutional and financial resources to implement effective adaptation are not available. Changes in the water balance can therefore have damaging effects on social and economic developments and can lead to enhanced conflicts between users over scarce water resources.

This study presents climate change impacts on the water sector in Africa, focussing on expected changes in regional water availability, the impacts of sea level rise, the vulnerability of the agricultural sector and impacts on agricultural productivity, and the projected increase in climate variability and extreme events. The vulnerability of African countries regarding water-related climate change impacts is analysed in the context of existing water management challenges, and trends caused by other factors such as population growth, economic growth and land use change are taken into account.

The study furthermore emphasises the relevance of climate change impacts for transboundary water management. Two case studies illustrate the complex effects of climate change on the management of shared water bodies for the Nile and the Orange river basins.