Mapping of suitable zones for manual drilling. An overview of the method and the application as decision tools

Manual drilling is regarded as a potential low cost solution to increase water supply in Africa, but it can be implemented only under specific hydrogeological conditions. The identification of suitable zones for manual drilling is a condition for an effective promotion and implementation of this technique. National maps of suitable zones have been produced since 2008, with a method based on the analysis of existing data and the integration with the experience of local experts. The method has been modified and improved, in particular with a more systematic procedure for the analysis of data and the integration of indirect environmental indicators. In the mean time different institutions have used these maps and evaluate their quality and their relevance as a decision tool for the promotion of manual drilling. In this paper the method of interpretation and the results achieved in terms of utility of these maps are discussed.