Transboundary Freshwater Spatial Database

Transboundary Freshwater Spatial Database

A simple map of the Columbia River basin

The Transboundary Freshwater Spatial Database contains physical, socioeconomic, and political data relating to the world's international river basins (which is synonymous with watershed and catchment).  First and foremost, this spatial database contains the delineations of the world's international river basins and their associated basin country units, which are the area of a particular basin in a certain country.  By breaking down the international river basins into BCUs - basin country units - we are able to understand how landcover, precipitation, population, withdrawal, consumption, and more vary between countries all within the same international river basin.  These data help us, in the PWCMT at OSU and other researchers worldwide, to manage our shared waters and to promote cooperation over them.  

The 2023 Spatial Database update identifies 313 international river basins, which are defined as having two general characteristics:

  1. system of surface and hydrologically connected groundwater flowing to a common terminus
  2. perennial (year-round) flow crossing or following an international political boundary

The river basin, then, is the area that can be extrapolated as area of land that drains waters to the common terminus, which is an ocean, sea, or terminal inland water body. For more information about the spatial database, please see the following paper:

Interactive Databases

Transboundary Freshwater Dispute Database - Interactive Map: 2018 Update
This geo-visualization was created by Hannah Friedrich, Giovanni Svevo, and Alex Walters, graduate students at OSU.  It presents the 310 international river basin delineations, their BCUs, biophysical, social, and political data in both search-able map and tabular formats, as well as new visualizations for the International Event Database and the International Freshwater Treaties Database

Transboundary Waters Assessment Programme - Interactive Data Portal: 2016 Update
The Transboundary Waters Assessment Programme (TWAP) was initiated by the Global Environment Facility to create a baseline assessment of all the planet's transboundary water resources. OSU Program in Water Conflict Management and Transformation's team of researchers completed an update of 286 international river basins and their associated BCUs to use a the baseline data for the River Basin Component of this comprehensive assessment.  The delineations and the full data from the project can be accessed through this data portal. 

Transboundary Freshwater Dispute Database - Interactive Map: 2014 Update
This visualization was created in partnership with the Northwest Alliance for Computational Science and Engineering at OSU.  It present the 276 international river basins and their associated BCUs, and biophysical, social and political data in both map and tabular formats. 

Data to Download

The GIS shapefiles and attribute data as part of the recent Updates of the Transboundary Freshwater Spatial Database  is available for download and use, please see the note on data use below.

  • 313 International River Basins - 2023 Update: This contains a zip file with two shapefiles: 1) international river basins and 2) basin country units and the codebook.  Both contain, in their attribute tables, tabular data associated with each basin or BCU. The attribute data is a work in progress and may be updated a few times a year. 
  • 313 International River Basins - 2023 Update Codebook: This is a document describing the data, data sources, citations, and other metadata information for the 2023 Update of the international river basin dataset. 
  • 286 International River Basins - 2016 TWAP Update: This contains a zip file with one shapefile of the basin country units for the 286 international river basins and attribute data associated with each basin.  For additional attribute data and indicators calculated as part of the TWAP Assessment, visit the TWAP Data Portal.
  • 276 International River Basins - 2014 Update: This contains a zip file with one shapefile of the basin country units for the 276 international river basins and attribute data associated with each basin, along with an excel sheet of data descriptions. This is not being updated, for more recent data see the 2018 dataset. 

Note on Data Use

Wide use of electronic and hardcopy versions of data, GIS coverages, and findings produced by the Transboundary Freshwater Diplomacy Database (TFDD) project is encouraged.  The data, coverages, and findings are not copyrighted, although due credit is appreciated.  Please attach this credit when citing TFDD products:

“Product of the Transboundary Freshwater Diplomacy Database, College of Earth, Ocean, and Atmospheric Sciences, Oregon State University.  Additional information about the TFDD can be found at:” 

If the product is to be used on the web, a hot link to the above address would be appreciated.




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