Approximately 40 per cent of the world’s population lives in river and lake basins that comprise two or more countries, and perhaps even more significantly, over 90 per cent lives in countries that share basins. The existing 276 transboundary lake and river basins cover nearly one half of the Earth’s land surface and account for an estimated 60 per cent of global freshwater flow. A total of 148 States include territory within such basins, and 21 countries lie entirely within them. In addition, about 2 billion people worldwide depend on groundwater, which includes approximately 300 transboundary aquifer systems.
The transboundary basins and aquifers link populations of different countries and support the incomes and livelihoods of hundreds of millions of people worldwide. All transboundary water bodies create hydrological, social and economic interdependencies between societies. They are vital for economic development, reducing poverty and contributing to the attainment of the Millennium Development Goals.
While embedding a potential for discourse and conflict, they provide opportunities for cooperation and promotion of regional peace and security as well as economic growth. Potential transboundary impacts and conflicting interests can best be solved by cooperation, adequate legal and institutional frameworks, joint approaches to planning and sharing of benefits and related costs.
Sources: Transboundary Waters: UN-Water Thematic Paper Sharing Benefits, Sharing Responsabilities, 2008; UNESCO, 2013