Territorial waters

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Schematic map of maritime zones (aerial view). Zonmar-en.svg
Schematic map of maritime zones (aerial view).

The term territorial waters is sometimes used informally to refer to any area of water over which a state has jurisdiction, including internal waters, the territorial sea, the contiguous zone, the exclusive economic zone and potentially the continental shelf. In a narrower sense, the term is used as a synonym for the territorial sea. [1]



Normally, the baseline from which the territorial sea is measured is the low-water line along the coast as marked on large-scale charts officially recognized by the coastal state. This is either the low-water mark closest to the shore, or alternatively it may be an unlimited distance from permanently exposed land, provided that some portion of elevations exposed at low tide but covered at high tide (like mud flats) is within 3 nautical miles (5.6 kilometres; 3 12 statute miles) of permanently exposed land. Straight baselines can alternatively be defined connecting fringing islands along a coast, across the mouths of rivers, or with certain restrictions across the mouths of bays. In this case, a bay is defined as "a well-marked indentation whose penetration is in such proportion to the width of its mouth as to contain land-locked waters and constitute more than a mere curvature of the coast. An indentation shall not, however, be regarded as a bay unless its area is as large as, or larger than, that of the semi-circle whose diameter is a line drawn across the mouth of that indentation". The baseline across the bay must also be no more than 24 nautical miles (44 kilometres; 28 statute miles) in length.

Internal waters

Internal and external territorial waters of the Philippines prior to the adoption of new baselines in 2009. Ph Territorial Map.png
Internal and external territorial waters of the Philippines prior to the adoption of new baselines in 2009.

Waters landward of the baseline are defined as internal waters, over which the state has complete sovereignty: not even innocent passage is allowed without explicit permission from said state. Lakes and rivers are considered internal waters. All "archipelagic waters" within the outermost islands of an archipelagic state such as Indonesia or the Philippines are also considered internal waters, and are treated the same with the exception that innocent passage through them must be allowed. However, archipelagic states may designate certain sea lanes through these waters.

Territorial sea

Territorial sea, as defined by the 1982 United Nations Convention on the Law of the Sea, [2] is a belt of coastal waters extending at most 12 nautical miles (22 km; 14 mi) from the baseline (usually the mean low-water mark) of a coastal state. The territorial sea is regarded as the sovereign territory of the state, although foreign ships (military and civilian) are allowed innocent passage through it, or transit passage for straits; this sovereignty also extends to the airspace over and seabed below. Adjustment of these boundaries is called, in international law, maritime delimitation.

A state's territorial sea extends up to 12 nmi (22 km; 14 mi) from its baseline. If this would overlap with another state's territorial sea, the border is taken as the median point between the states' baselines, unless the states in question agree otherwise. A state can also choose to claim a smaller territorial sea.

Conflicts have occurred whenever a coastal nation claims an entire gulf as its territorial waters while other nations only recognize the more restrictive definitions of the UN convention. Claims which draw baseline in excess of 24 nautical miles (two 12 NM limits) are judged excessive by the U.S. Two conflicts occurred in the Gulf of Sidra where Libya drew a line in excess of 230 nmi (430 km; 260 mi) and claimed the entire enclosed gulf as its territorial waters. The U.S. exercised freedom of navigation rights twice, in the 1981 and 1989 Gulf of Sidra incidents.

In the U.S. federal system, individual states exercise ownership (subject to federal law) up to 3 nmi (5.6 km; 3 12 mi) (9 nmi [17 km; 10 12 mi] for Texas and Florida) from shore, while the federal government exercises sole territorial jurisdiction further out (see Tidelands).

Contiguous zone

The contiguous zone is a band of water extending farther from the outer edge of the territorial sea to up to 24 nautical miles (44.4 km; 27.6 mi) from the baseline, within which a state can exert limited control for the purpose of preventing or punishing "infringement of its customs, fiscal, immigration or sanitary laws and regulations within its territory or territorial sea". This will typically be 12 nautical miles (22 km; 14 mi) wide, but could be more (if a state has chosen to claim a territorial sea of less than 12 nautical miles), or less, if it would otherwise overlap another state's contiguous zone. However, unlike the territorial sea, there is no standard rule for resolving such conflicts and the states in question must negotiate their own compromise. The United States invoked a contiguous zone out to 24 nmi from the baseline on 29 September 1999. [3]

Exclusive economic zone

An exclusive economic zone extends from the baseline to a maximum of 200 nautical miles (370.4 km; 230.2 mi), thus it includes the contiguous zone. [4] A coastal nation has control of all economic resources within its exclusive economic zone, including fishing, mining, oil exploration, and any pollution of those resources. However, it cannot prohibit passage or loitering above, on, or under the surface of the sea that is in compliance with the laws and regulations adopted by the coastal State in accordance with the provisions of the UN Convention, within that portion of its exclusive economic zone beyond its territorial sea. Before the United Nations Convention on the Law of the Sea of 1982, coastal nations arbitrarily extended their territorial waters in an effort to control activities which are now regulated by the exclusive economic zone, such as offshore oil exploration or fishing rights (see Cod Wars). Indeed, the exclusive economic zone is still popularly, though erroneously, called a coastal nation's territorial waters.

Continental shelf


Article 76 [5] gives the legal definition of continental shelf of coastal countries. For the physical geography definition, see the article continental shelf.

The continental shelf of a coastal nation extends out to the outer edge of the continental margin but at least 200 nautical miles (370 km; 230 mi) from the baselines of the territorial sea if the continental margin does not stretch that far. Coastal states have the right of exploration and exploitation of the seabed and the natural resources that lie on or beneath it, however other states may lay cables and pipelines if they are authorised by the coastal state. The outer limit of a country's continental shelf shall not stretch beyond 350 nautical miles (650 km; 400 mi) of the baseline, or beyond 100 nautical miles (190 km; 120 mi) from the 2,500 metres (8,200 ft) isobath, which is a line connecting the depths of the seabed at 2,500 meters.

The outer edge of the continental margin for the purposes of this article is defined as:

*a series of lines joining points not more than 60 nautical miles (110 km; 69 mi) apart where the thickness of sedimentary rocks is at least 1% of the height of the continental shelf above the foot of the continental slope; or
*a series of lines joining points not more than 60 nautical miles apart that is not more than 60 nautical miles from the foot of the continental margin.

The foot of the continental slope is determined as the point of maximum change in the gradient at its base.

The portion of the continental shelf beyond the 200 nautical mile limit is also known as the extended continental shelf. Countries wishing to delimit their outer continental shelf beyond 200 nautical miles have to submit scientific information for the basis of their claim to the UN Commission on the Limits of the Continental Shelf. The Commission then validates or makes recommendations on the scientific basis for the extended continental shelf claim. The scientific judgement of the Commission shall be final and binding. Validated extended continental shelf claims overlapping any demarcation between two or more parties are decided by bilateral or multilateral negotiation, not by the Commission.

Countries have ten years after ratifying UNCLOS to lodge their submissions to extend their continental shelf beyond 200 nautical miles, or by 13 May 2009 for countries where the convention was ratified before 13 May 1999. As of 1 June 2009, 51 submissions have been lodged with the Commission, of which eight have been deliberated by the Commission and have had recommendations issued. The eight are (in the order of date of submission): Russian Federation; Brazil; Australia; Ireland; New Zealand; the joint submission by France, Ireland, Spain and the United Kingdom; Norway and Mexico.

For full list, see below

Rights over the continental shelf

Articles 77 to 81 define the rights of a country over its continental shelf.

A coastal nation has control of all resources on or under its continental shelf, living or not, but no control over any living organisms above the shelf that are beyond its exclusive economic zone. This gives it the right to conduct hydrocarbon exploration and drilling works.


Territorial waters claims by coastal states in 1960 [6]
Breadth claimNumber of states
3-mile limit26
4-mile limit3
5-mile limit1
6-mile limit16
9-mile limit1
10-mile limit2
12-mile limit34
More than 12-miles9

From the eighteenth century until the mid twentieth century, the territorial waters of the British Empire, the United States, France and many other nations were three nautical miles (5.6 km) wide. Originally, this was the distance of a cannon shot, hence the portion of an ocean that a sovereign state could defend from shore. However, Iceland claimed two nautical miles (3.7 km), Norway and Sweden claimed four nautical miles (7.4 km), and Spain claimed 6 nautical miles (11 km; 6.9 mi) during this period. During incidents such as nuclear weapons testing and fisheries disputes some nations arbitrarily extended their maritime claims to as much as fifty or even two hundred nautical miles. Since the late 20th century the "12 mile limit" has become almost universally accepted. The United Kingdom extended its territorial waters from three to twelve nautical miles (22 km) in 1987.

During the League of Nations Codification Conference in 1930, the issue of establishing international legislation on territorial waters was raised, but no agreement was reached. [7]

Claims by legislation to the adjacent continental shelf and fishing was first made by the United States government immediately following the Second World War. On September 28, 1945, US President Harry S. Truman issued two proclamations that established government control of natural resources in areas adjacent to the coastline. One of these proclamation was titled "Policy of the United States With Respect to the Natural Resources of the Subsoil and Sea Bed of the Continental Shelf", and stipulated in its operative clause:

the Government of the United States regards the natural resources of the subsoil and sea bed of the continental shelf beneath the high seas but contiguous to the coasts of the United States as appertaining to the United States, subject to its jurisdiction and control. [8]

The second proclamation was titled "Policy of the United States With Respect to Coastal Fisheries in Certain Areas of the High Seas", and stated in its operative clause:

the Government of the United States regards it as proper to establish conservation zones in those areas of the high seas contiguous to the coasts of the United States wherein fishing activities have been or in the future may be developed and maintained on a substantial scale. [9]

Following the US Presidential proclamation, the issue of legally determining territorial waters by international agreement was raised, and in its first session in 1949, the International Law Commission of the United Nations added the subject to its agenda.

The important issue of the breadth of territorial waters could not be resolved at either the UNCLOS I (1956-1958) or UNCLOS II (1960) conferences, with neither the two major contenders of a 3-mile or 12-mile limit reaching the required two-thirds support. This lack of agreement had the potential to lead to serious international disputes. [6] It was only at the UNCLOS III (1973-1982) conference, whose provisions did not come into force until 1994, that this issue was resolved at twelve nautical miles.


Pirate radio broadcasting from artificial marine fixtures or anchored ships can be controlled by the affected coastal nation or other nations wherever that broadcast may originate, whether in the territorial sea, exclusive economic zone, the continental shelf or even on the high seas. [10]

Thus a coastal nation has total control over its internal waters, slightly less control over territorial waters, and ostensibly even less control over waters within the contiguous zones. However, it has total control of economic resources within its exclusive economic zone as well as those on or under its continental shelf.

Throughout this article, distances measured in nautical miles are exact legal definitions, while those in kilometres are approximate conversions that are not stated in any law or treaty.

Federal nations, such as the United States, divide control over certain waters between the federal government and the individual states. (See tidelands.)

Territorial sea claim

Maritime controversies involve two dimensions: (a) territorial sovereignty, which are a legacy of history; and (b) relevant jurisdictional rights and interests in maritime boundaries, which are mainly due to differing interpretations of the law of the sea. [11]

Special cases

Peru claims territorial waters out to 200 nmi. Maritime Claims of Ecuador and Peru.svg
Peru claims territorial waters out to 200 nmi.

Contiguous zone claims

Extended continental shelf claims

As of 13 May 2009, 51 submissions by 44 countries have been lodged for claims over their extended continental shelf. Some countries have multiple submissions and joint submissions with other countries. Recommendations have been given for 8 of the submissions.

Submissions with recommendations

List with date of submission and adoption of recommendation by the Commission on the Limits of the Continental Shelf. [29]

Other submissions

List in order of date of submission, with date of submission. [29]

See also


  1. DLM means that “the national legislation establishes the limits of a given zone only by reference to the delimitation of maritime boundaries with adjacent or opposite States, or to a median (equidistant) line in the absence of a maritime boundary delimitation agreement.”

Related Research Articles

United Nations Convention on the Law of the Sea International maritime law

The United Nations Convention on the Law of the Sea (UNCLOS), also called the Law of the Sea Convention or the Law of the Sea treaty, is an international agreement that resulted from the third United Nations Conference on the Law of the Sea, which took place between 1973 and 1982. The Law of the Sea Convention defines the rights and responsibilities of nations with respect to their use of the world's oceans, establishing guidelines for businesses, the environment, and the management of marine natural resources. The Convention, concluded in 1982, replaced the quad-treaty 1958 Convention on the High Seas. UNCLOS came into force in 1994, a year after Guyana became the 60th nation to ratify the treaty. As of June 2016, 167 countries and the European Union have joined in the Convention. It is uncertain as to what extent the Convention codifies customary international law.

Continental shelf A portion of a continent that is submerged under an area of relatively shallow water known as a shelf sea

A continental shelf is a portion of a continent that is submerged under an area of relatively shallow water known as a shelf sea. Much of these shelves has been exposed during glacial periods and interglacial periods. The shelf surrounding an island is known as an insular shelf.

Exclusive economic zone Adjacent sea zone in which a state has special rights

An exclusive economic zone (EEZ) is a sea zone prescribed by the 1982 United Nations Convention on the Law of the Sea over which a sovereign state has special rights regarding the exploration and use of marine resources, including energy production from water and wind. It stretches from the baseline out to 200 nautical miles (nmi) from the coast of the state in question. In colloquial usage, the term may include the continental shelf. The term does not include either the territorial sea or the continental shelf beyond the 200 nmi limit. The difference between the territorial sea and the exclusive economic zone is that the first confers full sovereignty over the waters, whereas the second is merely a "sovereign right" which refers to the coastal state's rights below the surface of the sea. The surface waters, as can be seen in the map, are international waters.

Lomonosov Ridge An underwater ridge of continental crust in the Arctic Ocean

The Lomonosov Ridge is an unusual underwater ridge of continental crust in the Arctic Ocean. It spans 1,800 kilometres (1,100 mi) between the New Siberian Islands over the central part of the ocean to Ellesmere Island of the Canadian Arctic Archipelago. The ridge divides the Arctic Basin into the Eurasian Basin and the Amerasian Basin. The width of the Lomonosov Ridge varies from 60 to 200 kilometres. It rises 3,300 to 3,700 metres above the 4,200-metre (13,800 ft) deep seabed. The minimum depth of the ocean above the ridge is less than 400 metres (1,300 ft). Slopes of the ridge are relatively steep, broken up by canyons, and covered with layers of silt.

James Shoal

James Shoal is an underwater shoal (bank) in the South China Sea, with a depth of 22 metres (72 ft) below the surface of the sea, located about 45 nautical miles off the Borneo coast of Malaysia. It is claimed by Malaysia, the People's Republic of China, and the Republic of China (Taiwan). The shoal and its surrounds are administered by Malaysia.

Ambalat Place

Ambalat is a sea block in the Celebes sea located off the east coast of Borneo. It lies to the east of the Indonesian province of North Kalimantan and to the south-east of the Malaysian state of Sabah, and it is the subject of a territorial dispute between the two nations. Malaysia refers to part of the Ambalat block as Block ND6 (formerly Block Y) and part of East Ambalat Block as Block ND7 (formerly Block Z). The deep sea blocks contain an estimated 62,000,000 barrels (9,900,000 m3) of oil and 348 million cubic meters of natural gas. Other estimates place it substantially higher: 764,000,000 barrels (121,500,000 m3) of oil and 3.96 × 1010 cubic meters (1.4 trillion cubic feet) of gas, in only one of nine points in Ambalat.

Argentine Sea The sea within the continental shelf off the Argentine mainland

The Argentine Sea is the name given to the sea within the continental shelf off the Argentine mainland. It lacks international recognition but is symbolically important to Argentina for consolidating the country's national unity behind the concept of Argentine irridentism, an area that extends out to include the British South Atlantic islands and a section of the Antarctic continent.

Territorial claims in the Arctic

The Arctic consists of land, internal waters, territorial seas, exclusive economic zones (EEZs) and international waters above the Arctic Circle. All land, internal waters, territorial seas and EEZs in the Arctic are under the jurisdiction of one of the eight Arctic coastal states: Canada, Denmark, Finland, Iceland, Norway, Russia, Sweden and the United States. International law regulates this area as with other portions of Earth.

Outer Continental Shelf Maritime U.S. federal zone of jurisdiction beyond the jurisdiction of the individual states

The Outer Continental Shelf (OCS) is a peculiarity of the political geography of the United States. The OCS is the part of the internationally recognized continental shelf of the United States which does not fall under the jurisdictions of the individual U.S. states.

Malaysia and Vietnam are two Southeast Asian countries with maritime boundaries which meet in the Gulf of Thailand and South China Sea. The two countries have overlapping claims over the continental shelf in the Gulf of Thailand. Both countries have, however, come to an agreement to jointly exploit the natural resources in the disputed area pending resolution of the dispute over sovereignty.

Australia–Indonesia border international maritime border

The Australia–Indonesia border is a maritime boundary running west from the two countries' tripoint maritime boundary with Papua New Guinea in the western entrance to the Torres Straits, through the Arafura Sea and Timor Sea, and terminating in the Indian Ocean. The boundary is, however, broken by the Timor Gap, where Australian and East Timorese territorial waters meet and where the two countries have overlapping claims to the seabed.

Benham Rise seismically active undersea region and extinct volcanic ridge located in the Philippine Sea

The Benham Rise, also known as the Philippine Rise, is an extinct volcanic ridge located in the Philippine Sea approximately 250 km (160 mi) east of the northern coastline of Dinapigue, Isabela. The Rise has been known to the people of Catanduanes as Kalipung-awan since pre-colonial times, which literally means 'loneliness from an isolated place'.

Spratly Islands dispute territorial dispute

The Spratly Islands dispute is an ongoing territorial dispute between China, Taiwan, Malaysia, the Philippines, Vietnam, and Brunei, concerning "ownership" of the Spratly Islands, a group of islands and associated "maritime features" located in the South China Sea. The dispute is characterised by diplomatic stalemate and the employment of military pressure techniques in the advancement of national territorial claims. All except Brunei occupy some of the maritime features.

East China Sea EEZ disputes

There are disputes between China, Japan, and South Korea over the extent of their respective exclusive economic zones (EEZs) in the East China Sea.

Rockall Bank dispute

Several states have claimed interests over the sea bed adjoining Rockall. Denmark, Iceland, Ireland and the United Kingdom have all made submissions to the commission set up under the United Nations Convention on the Law of the Sea (UNCLOS).

Exclusive economic zone of Japan

Japan has the eighth largest exclusive economic zone (EEZ) in the world. The total area of Japan is about 377,975.24 km2. Japan's EEZ area is vast and the territorial waters and EEZ together is about 4.48 million km2.

Exclusive economic zone of Australia

Australia's exclusive economic zone (EEZ) was declared on 1 August 1994 and extends from 12 to 200 nautical miles from the coastline of Australia and its external territories, except where a maritime delimitation agreement exists with another state. To the 12 nautical-mile boundary is Australia's territorial waters. Australia has the third-largest exclusive economic zone, behind the United States and France but ahead of Russia, with the total area of 8,148,250 square kilometres (3,146,060 sq mi), which exceeds its land territory.

The borders of Indonesia include land and maritime borders with Malaysia, Papua New Guinea, and Timor Leste, as well as shared maritime boundaries with Australia, India, Palau, Philippines, Singapore, Thailand, and Vietnam.

Exclusive economic zone of India

India has the 18th-largest exclusive economic zone (EEZ) with a total size of 2,305,143 km2 (890,021 sq mi). It includes the Lakshadweep island group in the Laccadive Sea off the southwestern coast of India and the Andaman and Nicobar Islands at the Bay of Bengal and the Andaman Sea. India's EEZ is bordered to the west by Pakistan, to the south by the Maldives and Sri Lanka and to the east by Bangladesh, Myanmar, Thailand, Malaysia and Indonesia.

Canada's EEZ is the 7th largest in the world. It is unusual in that its exclusive economic zone, covering 5,599,077 km2 (2,161,816 sq mi), is slightly smaller than its territorial waters. The latter generally extend only 12 nautical miles from the shore, but also include inland marine waters such as Hudson Bay, the Gulf of Saint Lawrence and the internal waters of the Arctic archipelago.


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