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Law of the Sea

Introduction​

The Law of the Sea is the branch of public international law that governs the rights and responsibilities of States in their use of the world's oceans and seas. It regulates matters such as the delimitation of maritime zones, navigation, the exploitation of living and non-living resources, marine scientific research, and the protection of the marine environment.

The principal source of this law today is the United Nations Convention on the Law of the Sea (UNCLOS), 1982, which entered into force in 1994 and is often described as the "constitution for the oceans." India signed UNCLOS in 1982 and ratified it in 1995. Domestically, India gives effect to its maritime zones through the Territorial Waters, Continental Shelf, Exclusive Economic Zone and Other Maritime Zones Act, 1976.

This guide outlines the main maritime zones and the legal principles that apply to each, with particular attention to the Indian legal framework. It is intended for LLB and LLM students studying public international law.

The Baseline​

Maritime zones are measured seaward from a baseline. The normal baseline is the low-water line along the coast as marked on official charts. Where the coastline is deeply indented or fringed with islands, States may draw straight baselines connecting appropriate points. The breadth of every zone below is calculated from this baseline.

Internal Waters​

Waters landward of the baseline (ports, bays, river mouths, and harbours) are internal waters. The coastal State exercises full sovereignty over them, equivalent to sovereignty over its land territory. Unlike in the territorial sea, foreign vessels enjoy no general right of innocent passage through internal waters.

Territorial Sea​

  • Breadth: up to 12 nautical miles from the baseline (UNCLOS Article 3).
  • Legal status: The coastal State has sovereignty over the territorial sea, its seabed and subsoil, and the airspace above it.
  • Key limitation — innocent passage: Foreign ships (including warships, subject to debate and to notification requirements imposed by some States) enjoy the right of innocent passage. Passage is "innocent" so long as it is not prejudicial to the peace, good order, or security of the coastal State (UNCLOS Articles 17–19).

In India, the territorial waters extend to 12 nautical miles and are declared under the Maritime Zones Act, 1976. India's sovereignty over this belt is complete, subject to the right of innocent passage recognised in international law.

Contiguous Zone​

  • Breadth: up to 24 nautical miles from the baseline (UNCLOS Article 33).
  • Rights of the coastal State: The coastal State does not have sovereignty here but may exercise the control necessary to prevent and punish infringement of its customs, fiscal, immigration, and sanitary (health) laws that occur within its territory or territorial sea.

Exclusive Economic Zone (EEZ)​

  • Breadth: up to 200 nautical miles from the baseline (UNCLOS Article 57).
  • Sovereign rights: The coastal State has sovereign rights for the purpose of exploring, exploiting, conserving, and managing the natural resources — living and non-living — of the waters, seabed, and subsoil, together with rights over activities such as energy production from water, currents, and wind (UNCLOS Articles 56–58).
  • Freedoms retained by other States: Other States continue to enjoy the freedoms of navigation and overflight and of laying submarine cables and pipelines within the EEZ.

India proclaimed a 200-nautical-mile EEZ under the Maritime Zones Act, 1976, giving it exclusive rights over the resources of one of the world's larger exclusive economic zones.

Continental Shelf​

  • Definition: The continental shelf comprises the seabed and subsoil extending beyond the territorial sea throughout the natural prolongation of the land territory to the outer edge of the continental margin, or to 200 nautical miles where the margin does not extend that far. Subject to the recommendations of the Commission on the Limits of the Continental Shelf, it may in defined geological circumstances extend further (UNCLOS Articles 76–77).
  • Rights: The coastal State exercises sovereign rights over the shelf for the purpose of exploring it and exploiting its natural resources (mineral resources and sedentary species). These rights are inherent and do not depend on occupation or express proclamation.

High Seas​

  • Definition: All parts of the sea not included in the EEZ, territorial sea, or internal waters of any State (UNCLOS Article 86).
  • Governing principle — freedom of the high seas (UNCLOS Article 87): The high seas are open to all States and include the freedoms of navigation, overflight, laying submarine cables and pipelines, constructing artificial installations, fishing (subject to conservation obligations), and scientific research.
  • No appropriation: No State may validly purport to subject any part of the high seas to its sovereignty (UNCLOS Article 89).
  • Flag-State jurisdiction: Ships on the high seas are generally subject to the exclusive jurisdiction of the State whose flag they fly, subject to recognised exceptions such as piracy.

The Area and the Common Heritage of Mankind​

The seabed and subsoil beyond the limits of national jurisdiction are known as "the Area." Under UNCLOS Part XI, the Area and its resources are the common heritage of mankind; activities there are administered for the benefit of humanity as a whole under the supervision of the International Seabed Authority (ISA), based in Kingston, Jamaica.

Dispute Settlement​

UNCLOS establishes a comprehensive system for the peaceful settlement of disputes (Part XV). Parties may choose among several fora, including:

  • the International Tribunal for the Law of the Sea (ITLOS), based in Hamburg, Germany;
  • the International Court of Justice (ICJ);
  • arbitral tribunals constituted under Annex VII; and
  • special arbitral tribunals under Annex VIII.

A well-known dispute involving India was the "Enrica Lexie" incident between Italy and India, arising from the shooting of two Indian fishermen by Italian marines aboard the oil tanker Enrica Lexie off the Kerala coast in 2012. The matter was referred to arbitration under Annex VII of UNCLOS, and the tribunal's 2020 award addressed the competing jurisdictional claims of the two States and questions of immunity.

Marine Environmental Protection​

UNCLOS Part XII imposes a general obligation on all States to protect and preserve the marine environment and to prevent, reduce, and control pollution of the sea from various sources. In India, coastal and marine conservation is pursued through instruments such as Coastal Regulation Zone notifications issued under the Environment (Protection) Act, 1986, and the establishment of marine protected areas to conserve marine biodiversity.

Conclusion​

The Law of the Sea balances the sovereignty and resource interests of coastal States against the community interest in freedom of navigation and the shared use of the oceans. UNCLOS provides the framework of maritime zones — internal waters, territorial sea, contiguous zone, EEZ, continental shelf, high seas, and the Area — each carrying a distinct balance of rights and duties. India gives domestic effect to these zones through the Maritime Zones Act, 1976, while remaining bound by its obligations under UNCLOS.

Suggested Reading​

  1. United Nations Convention on the Law of the Sea (UNCLOS), 1982.
  2. The Territorial Waters, Continental Shelf, Exclusive Economic Zone and Other Maritime Zones Act, 1976 (India).
  3. R.P. Anand, Origin and Development of the Law of the Sea.
  4. Malcolm N. Shaw, International Law (chapter on the Law of the Sea).