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Marine and Freshwater


Portions of a geographical area which constitutes a hydrogeological unit as the catchment area for a single river which are under the jurisdiction of two or more countries. (Source: GEMET/WPRa)

Transboundary waters means any surface or ground waters which mark, cross or are located on boundaries between two or more States; wherever transboundary waters flow directly into the sea, these transboundary waters end at a straight line across their respective mouths between points on the low-water line of their banks (Source: 1992 Water Convention, Art.1)


Alternative labels:
international lake
international river basin
international water
transboundary water
transboundary watercourse

In other languages

cours d'eau international
международный водный путь
cursos de agua internacionales
مجرى مائي دولي

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Follow up the links below to see InforMEA content related to international watercourse coming up from several external sources.

Multilateral environment agreements tagged with international watercourse

You can see below a list of multilateral environment agreements. Use the links on the right to view the content tagged with international watercourse. This includes official treaty texts, decisions, recommendations, and other related informational documents such as publications, annuals, meetings, documents or reports.
The Water Convention
Convention on the Transboundary Effects of Industrial Accidents


UN Watercourses Convention Online User´s Guide

Interviews on the UNECE Water Convention

Videolecture - Evolution, Codification and Current Status of International Water Law