Intensive groundwater use in urban areas: the case of megacities

Today, almost half the world’s 6,000 million population live in urban areas with some 20 megacities supporting over 10 million inhabitants. Within 25 years, the world’s population is expected to exceed 8,000 million; the vast majority of these additional people will be urban dwellers. Demand for safe water supplies already poses an enormous burden on available resources and there is an urgent need to identify the courses of action required if continued growth of the world’s cities is to be sustained. Historically, intensive use of groundwater has been a key factor in much of this development, and while it can continue to play a key role, new technologies and carefully planned management and protection strategies are required to increase supply, reduce demand and make more efficient use of the resource. In most rapidly growing cities, the challenge will be to meet increasing demands for safe water supply in the face of competing political, societal and economic issues and limited financial resources for technological development and essential infrastructure.