Column Actions

Ensure availability and sustainable management of water and sanitation for all.

The proportion of transboundary basin area with an operational arrangement for water cooperation is defined as the proportion of transboundary basins area within a country with an operational arrangement for water cooperation. It is derived by adding up the surface area in a country of those transboundary surface water catchments and transboundary aquifers (i.e. ‘transboundary’ basins) that are covered by an operational arrangement and dividing the obtained area by the aggregate total area in a country of all transboundary basins (both catchments and aquifers). The result is multiplied by 100 to obtain it expressed as percentage share.

National Hydrological Service

Statistical Institute of Belize

National Hydrological Service

Every 3 years

Percentage (%)

Most of the world’s water resources are shared: 592 transboundary aquifers have been identified and transboundary lake and river basins cover nearly one half of the Earth’s land surface and account for an estimated 60% of global freshwater. Approximately 40% of the world’s population lives in river and lake basins shared by two or more countries and over 90% lives in countries that share basins. Development of water resources has impacts across transboundary basins, potentially on co-riparian countries, and use of surface water or groundwater may affect the other resource, these usually being interlinked. Intensive water use, flow regulation or pollution risks going as far as compromising co-riparian countries’ development aspirations and therefore transboundary cooperation is required. However, cooperation is in most cases not advanced.

To implement integrated water resources management at all levels, including through transboundary cooperation as appropriate.

Data would be most reliably collected at the national level. Basin level data can also be disaggregated to country level (for national reporting) and aggregated to regional and global level.

The calculations can most easily be carried with Geographical Information Systems (GIS). Once generated, with appropriate tools for spatial analysis, the shapes of the surface catchments and the aquifers can be used to report both disaggregated (for the surface water basin or aquifer) and aggregated (agreement exists on either one).

To measure the proportion of transboundary basin area with an operational arrangement for water cooperation.

The legal basis for cooperation develops slowly: conclusion of new agreements on transboundary waters is commonly a long process that takes many years.

The information on the areal extent of transboundary aquifers may evolve over time as such information is generally more coarse but likely to improve because of the evolving knowledge on aquifers. Technical studies and exchange of information will improve the delineation and might also lead to the identification of additional transboundary aquifers.