International waters

This article is about the waters outside national jurisdictions. For the comedy podcast, see International Waters (podcast).

"Mare liberum" redirects here. For the 1609 book by Hugo Grotius, see Mare Liberum.

International ownership treaties
Antarctic Treaty System Law of the Sea Outer Space Treaty Moon Treaty International waters

Areas outside of exclusive economic zones in dark blue.

The terms international waters or trans-boundary waters apply where any of the following types of bodies of water (or their drainage basins) transcend international boundaries: oceans, large marine ecosystems, enclosed or semi-enclosed regional seas and estuaries, rivers, lakes, groundwater systems (aquifers), and wetlands.^[1]

Oceans, seas, and waters outside of national jurisdiction are also referred to as the high seas or, in Latin, mare liberum (meaning free sea).

Ships sailing the high seas are generally under the jurisdiction of the flag state (if there is one);^[2] however, when a ship is involved in certain criminal acts, such as piracy,^[3] any nation can exercise jurisdiction under the doctrine of universal jurisdiction. International waters can be contrasted with internal waters, territorial waters and exclusive economic zones.

International waterways

Komárno in Slovakia is an inland port on the Danube River which is an important international waterway.

Several international treaties have established freedom of navigation on semi-enclosed seas.

The Copenhagen Convention of 1857 opened access to the Baltic by abolishing the Sound Dues and making the Danish Straits an international waterway free to all commercial and military shipping.
Several conventions have opened the Bosporus and Dardanelles to shipping. The latest, the Montreux Convention Regarding the Regime of the Turkish Straits, maintains the straits' status as an international waterway.

Other international treaties have opened up rivers, which are not traditionally international waterways.

The Danube River is an international waterway so that landlocked Austria, Hungary, Serbia, and Slovakia can have secure access to the Black Sea.

Disputes over international waters

Atlantic Ocean - the main zone of sea transport in 15th-20th centuries.

Current unresolved disputes over whether particular waters are "International waters" include:

The Arctic Ocean: While Canada, Denmark, Russia and Norway all regard parts of the Arctic seas as national waters or internal waters, most European Union countries and the United States officially regard the whole region as international waters.
The Southern Ocean: Australia claims an exclusive economic zone (EEZ) around its Antarctic territorial claim. Since this claim is only recognised by four other countries, the EEZ claim is also disputed.

In addition to formal disputes, the government of Somalia exercises little control de facto over Somali territorial waters. Consequently, much piracy, illegal dumping of waste and fishing without permit has occurred.

Although water is often seen as a source of conflict, recent research suggests that water management can be a source for cooperation between countries. Such cooperation will benefit participating countries by being the catalyst for larger socio-economic development.^[4] For instance, the countries of the Senegal River Basin that cooperate through the Organisation pour la Mise en Valeur du Fleuve Sénégal (OMVS) have achieved greater socio-economic development and overcome challenges relating to agriculture and other issues.^[5]