International River Basin Register

Register of International River Basins

The Register of International River Basins is a list that identifies the world's international rivers basins.  Originally begun in 1978 by the now-defunct United Nations Department of Economic and Social Affairs, the Transboundary Freshwater Dispute Database has been responsible for maintaining and up-dating the register since 1999.  Below you can find the current and previous Registers of International River Basins, links to download the current Register's data, and maps from the current Register. 

Current Register of International River Basins - 2018

The tabular data for the current Register of International River Basins is available to download.  It includes the list of 310 international river basins and their associated basin country units (BCU) and area calculations.  The spatial delineations and geographic information system (GIS) shapefiles are available as a part of the Spatial Database

Historical Evolution of the Register of International River Basins

There have been three Registers and two updates produced as a part of other projects on international river basins. The following table lists the number of international river basins and the total percentages of land area within an international river basin (excluding Antarctica). These numbers have changed over time and represent a snapshot in time of the rivers that meet the criteria to be considered international.  Changes to political borders and increases in remote sensing technology are the two primary reasons for the increase in number of international river basins. 

Register Number of Basins Percentage of the
World's Land Surface
1978 Register           214 47.0%
1999 Register            261 45.3%
2010 Update           276 46.1%
2016 Update           286 46.2%
2018 Register           310 47.1%


Maps from the 2018 Register of International River Basins

All maps below can be downloaded at full resolution from the Map and Image Galleries.