LEGAL STATUS OF ARTIFICIAL ISLANDS

I. Introduction

Technological advancements, population density, insufficient coastal areas, and the need to utilize marine resources have led states to create new living and activity areas at sea. Airports, port facilities, energy production centers, oil and natural gas platforms, tourism areas, and logistics bases created by reclaiming land from the sea are prime examples of this development. While artificial islands offer significant economic and strategic benefits, they also raise serious legal issues concerning state sovereignty, the delimitation of maritime areas, navigational safety, and the protection of the marine environment.

The fundamental issue in determining the legal status of artificial islands is whether these structures produce the same results as natural islands. A state constructing a large-scale artificial island near its coast may effectively extend its coastline into the sea. However, a change in the physical coastline does not automatically result in a corresponding expansion of maritime jurisdiction under international law. A contrary approach would allow states with significant engineering and economic power to unilaterally expand their territorial waters, exclusive economic zones, and continental shelves by reclaiming land from the sea.

Therefore, international maritime law makes a clear distinction between natural geographical formations and man-made structures. Coastal states may have administrative and regulatory powers over artificial islands; however, artificial islands cannot create independent territorial waters, exclusive economic zones, or continental shelves. While an artificial island is a structure over which sovereignty and jurisdiction can be exercised, it is not considered a "land territory" that creates maritime jurisdiction.

II. The Concept of Artificial Islands and Their Distinction from Natural Islands

The United Nations Convention on the Law of the Sea does not provide a comprehensive and general definition of an artificial island. However, based on various provisions of the Convention, an artificial island can be defined as a man-made structure or landmass created on the seabed that remains above the water and is fixed or permanent. The structure can be created by filling, anchoring to the seabed, or using specific engineering systems.

A natural island is defined in Article 121 of the United Nations Convention on the Law of the Sea as a naturally formed landmass surrounded by water that remains above water when the tide rises. The requirement of "natural formation" in this definition constitutes the fundamental distinction between artificial and natural islands. A landmass created by human hands, regardless of its size, population, or economic importance, does not acquire natural island status solely on the basis of these characteristics.

In determining the legal status of an artificial island, the form and function of the structure, not its name, should be the primary consideration. A structure may be referred to as an "island," "terminal," "platform," "naval base," or "offshore facility" in official documents. However, this naming does not automatically classify it as a natural island under international law. Similarly, filling in and expanding a pre-existing rock or tidal elevation does not alter the legal status of that geographical feature, which stems from its natural state.

The arbitration panel established within the Permanent Court of Arbitration in the South China Sea Arbitration clearly stated that the status of maritime features should be determined according to their natural state prior to human-induced alterations. Accordingly, a tidal rise cannot be filled in to create an island; similarly, a rocky islet cannot be transformed into an island with full maritime jurisdiction through extensive construction activities.

This approach is a consequence of the principle that maritime jurisdiction areas should be based on natural geography. Otherwise, states could establish new sovereignty and maritime jurisdiction claims by filling in disputed shoals or the seabed.

III. Legal Status of Artificial Islands in Different Maritime Areas

A. Artificial Islands in Inland and Territorial Waters

Internal waters and territorial waters are maritime areas subject to the sovereign authority of the coastal state. The sovereignty of the coastal state extends beyond the waterline to the seabed, subsoil, and airspace above its territorial waters. However, foreign vessels enjoy the right of innocent passage in these territorial waters.

A coastal state has the right to permit the construction of artificial islands in its internal or territorial waters, to determine the conditions of construction, to regulate the intended use of the structure, and to exercise administrative, criminal, financial, customs, and security powers over the structure. However, the construction of artificial islands must not impede the right of innocent passage of foreign vessels or international navigation in a manner contrary to law.

An artificial island constructed within territorial waters does not create new territorial waters belonging to the coastal state, even though it is under its sovereignty. An artificial island does not automatically become a new coastal point or baseline for measuring territorial waters. Article 11 of the United Nations Convention on the Law of the Sea, concerning ports, stipulates that the outermost permanent port facilities forming an integral part of the port system may be considered part of the coast; however, facilities offshore and artificial islands are not included within this scope.

Therefore, it is important to determine whether a reclaimed land area near the coast is a continuous facility integrated into the port system or an independent artificial island. This distinction can have legal consequences, particularly with regard to the coastline and port boundaries used for measuring territorial waters.

B. Artificial Islands in the Exclusive Economic Zone

The exclusive economic zone is not an area under the full sovereignty of the coastal state. The coastal state possesses sovereign rights in this zone regarding the exploration, exploitation, conservation, and management of living and non-living natural resources; and certain jurisdictional and regulatory powers with respect to artificial islands, facilities, and structures.

According to Article 60 of the United Nations Convention on the Law of the Sea, a coastal state has the exclusive right to construct, permit, and regulate the construction of artificial islands, facilities, and structures within its exclusive economic zone. Furthermore, the coastal state may exercise exclusive jurisdiction over these structures, including customs, finance, health, security, and immigration regulations.

However, the coastal state's authority over artificial islands is not unlimited due to the legal nature of the exclusive economic zone. Other states retain their rights of navigation, flight, and the laying of submarine cables and pipelines. The coastal state must exercise due diligence in respecting these rights of other states during the construction and operation of artificial islands. Other states, in turn, must respect the coastal state's authority when exercising their own rights.

C. Artificial Islands on the Continental Shelf

The continental shelf grants the coastal state exclusive sovereign rights to explore and exploit the natural resources on and under the seabed. These rights of the coastal state are not subject to actual occupation or declaration.

According to Article 80 of the United Nations Convention on the Law of the Sea, the provisions of Article 60 concerning artificial islands, installations and structures in the exclusive economic zone also apply, with necessary modifications, to the continental shelf. Therefore, the coastal state has the authority to permit and supervise the construction of platforms, installations or artificial islands for the purpose of exploring and exploiting natural resources on the continental shelf.

However, rights over the continental shelf do not alter the legal status of the water column. The waters above the continental shelf may be the high seas or the exclusive economic zone of another state. Therefore, a coastal state cannot unnecessarily obstruct navigation and the legitimate usage rights of other states when exercising its rights over the seabed.

D. Artificial Islands in the Open Sea

The high seas are not subject to the sovereignty of any state. States have the freedom to navigate, fly, fish, conduct scientific research, and construct artificial islands and facilities permitted by international law in the high seas. However, this freedom is not unlimited and is conditional upon due respect being given to the rights of other states to enjoy the high seas.

The construction of an artificial island in the open sea does not grant the constructing state sovereignty over the surrounding maritime area. A state cannot annex a portion of the open sea to its territory by creating an artificial island. Furthermore, the provisions of the United Nations Convention on the Law of the Sea concerning the international seabed must be considered separately for activities to be carried out in areas of the seabed outside national jurisdiction.

IV. The Impact of Artificial Islands on Maritime Jurisdiction and Delimitation

Artificial islands do not have the status of natural islands under international maritime law. Article 60, paragraph eight, of the United Nations Convention on the Law of the Sea explicitly stipulates that artificial islands do not have island status, do not possess their own territorial waters, and their existence does not affect the delimitation of territorial waters, exclusive economic zones, or continental shelf boundaries.

This provision leads to three main consequences.

Firstly, an independent territorial water zone is not formed around the artificial island. The coastal state may establish a designated zone for security purposes; however, this area is not territorial water. The security zone is merely a functional area intended to protect the structure and navigation.

Secondly, an artificial island does not create an exclusive economic zone or continental shelf. The presence of a permanent population, economic activity, a port, or an airport on the artificial island does not change this conclusion.

Thirdly, artificial islands cannot be used as coastal points in maritime delimitation between states. A state cannot expand its maritime area by using an artificial island as a basis for delimiting territorial waters, exclusive economic zones, or continental shelf boundaries with another state on the opposite coast.

The ineffectiveness of artificial islands in delimiting maritime boundaries is essential for equity and stability. Allowing maritime boundaries to become dependent on subsequently constructed engineering activities would disrupt the balance between states and create constant disputes. Therefore, the geography used as the basis for delimitation assessments is, as a rule, the natural coastal geography.

V. Construction Permits, Security Zones and Navigation Safety

The construction of artificial islands can create serious navigational risks, especially in areas with heavy maritime traffic. Therefore, the coastal state should properly announce the existence of the artificial island, place permanent warning signs, and ensure that the structure is shown on nautical charts.

According to Article 60 of the United Nations Convention on the Law of the Sea, a coastal state may establish reasonable safety zones around artificial islands. The width of these safety zones shall not exceed 500 meters from the outer edge of the structure, unless a wider area is prescribed by generally accepted international standards or by a competent international organization. All vessels must comply with these safety zones and observe accepted standards of navigation around the structure.

The purpose of the safety zone is not to grant the coastal state a new area of ​​sovereignty, but to ensure the safety of the facility, its personnel, and passing vessels. Therefore, prohibitions and restrictions applied within the safety zone must be proportionate. The size of the safety zone should be determined taking into account the type of facility, maritime traffic, meteorological conditions, and the potential impact of accidents.

Artificial islands and security zones cannot be created in a way that obstructs the use of essential and recognized waterways for international navigation. In particular, in projects involving straits, busy trade routes, and port access channels, freedom and safety of navigation must be given priority.

The removal of artificial islands and facilities that have ceased to be used or have been abandoned is also important. International law mandates the removal of abandoned or unused facilities, taking into account navigational safety. The location, depth, and dimensions of any parts that cannot be completely removed should be appropriately declared. Fishing, marine environment, and the rights of other states must also be considered during removal operations.

VI. Protection of the Marine Environment and Environmental Responsibility

Artificial island projects can have serious impacts on the marine ecosystem due to risks such as seabed dredging, landfill transportation, alteration of coastal currents, habitat loss, turbidity, noise, waste generation, and pollution. Therefore, artificial island construction is not only a matter of sovereignty or ownership, but also an environmental law issue.

The United Nations Convention on the Law of the Sea imposes a general obligation on states to protect and conserve the marine environment. Legislation must be adopted and implemented to prevent, reduce, and control pollution from seabed activities and artificial islands, facilities, and structures under the jurisdiction of states.

Environmental impact assessments for artificial island projects should cover not only the construction phase but also the operation and decommissioning phases. The project's impact on ocean currents, coastal erosion, water quality, fishing grounds, seagrass meadows, coral reefs, and protected species should be investigated. If there is a possibility of a significant transboundary environmental impact, information sharing and cooperation with other states may also be considered.

In terms of environmental responsibility, the polluter pays principle, the precautionary principle, and the approach of preventing harm at its source are important. If marine pollution occurs as a result of the negligent activity of the organization constructing or operating the artificial island, administrative, legal, and, where necessary, criminal liability may arise. The damage is not limited solely to cleanup costs. Loss of fishing revenue, tourism losses, ecological restoration expenses, and damage to the property of third parties may also be covered by compensation.

The fact that an artificial island project is based on permission from a public authority does not automatically absolve the operator of environmental damage. Permission allows the activity to be carried out under specific conditions; it does not eliminate responsibility arising from activities that violate environmental regulations or are carried out without due diligence.

VII. The Relationship Between Artificial Islands and Maritime Trade Law

A. Whether an Artificial Island Counts as a Ship

The first issue in evaluating artificial islands from the perspective of maritime trade law is whether these structures qualify as vessels. According to Article 931 of the Turkish Commercial Code, a vessel whose intended purpose requires movement in water, possesses buoyancy, and is not excessively small, is considered a vessel regardless of whether it is capable of self-propulsion. Vessels dedicated to or actually used for the purpose of generating economic benefit are considered merchant vessels.

The purpose of an artificial island, whether permanently anchored to the seabed or created by land reclamation, does not require it to move in the water. Therefore, fixed artificial islands are, as a rule, not considered ships within the meaning of the Turkish Commercial Code. The mere fact that an artificial island is located on the sea or is accessible by sea is not sufficient for it to be considered a ship.

Conversely, the legal status of certain floating, towable, or submersible platforms should be assessed according to the specific characteristics of the case. The intended purpose of the structure, its mobility in water, whether its connection to the seabed is permanent, and its operational model are important factors. It is possible that a structure to be fixed in place after construction may be considered a ship during the transportation phase, but may lose this status after it is fixed in place.

B. Construction and Maritime Transport Contracts

The construction of artificial islands requires large quantities of stone, sand, steel, concrete, and technical equipment. The transportation of these materials by sea gives rise to transportation contracts and freight relationships. The carrier's liability in the event of damage, delay, or complete loss of the cargo on board is determined within the framework of the transportation contract and applicable international rules.

Dredging vessels, tugboats, heavy-lift vessels, floating cranes, and supply vessels are essential elements of artificial island projects. The use of these vessels can give rise to complex legal relationships involving intertwined ship charter agreements, time charter agreements, voyage charter agreements, towage, equipment rental, service contracts, and works contracts.

The actual performance of the parties is more important than the name of the contract. For example, the allocation of a heavy-lift vessel with specific equipment to a project can be classified as a ship charter, time charter, or service contract, depending on who retains control of the vessel's technical management.

C. Damage Caused by Collisions and Fixed Structures

If a ship collides with an artificial island, platform, pier, or facilities surrounding a structure, significant damage may occur. The fact that a fixed artificial island is not considered a ship does not absolve the ship operator of liability. Depending on the nature of the incident, tort, breach of contract, port and navigation regulations, and provisions of maritime trade law relating to ship liability may apply.

If the accident is caused by the artificial island not being properly marked, not being shown on nautical charts, or the safety systems not functioning, the owner or operator of the structure may also be held liable. Conversely, if the accident is caused by unsafe navigation, captain's error, or a technical malfunction, the ship operator, owner, or other relevant parties may be held responsible.

In cases where multiple factors contributed to the accident, the apportionment of contributory negligence and damages between the parties should be considered. Furthermore, whether the ship owner has the right to limit their liability should be examined separately within the framework of applicable law and international conventions.

D. Marine Insurance

In artificial island projects, a single traditional insurance policy is insufficient. Construction insurance covering all risks, installation insurance, third-party liability insurance, and environmental liability insurance may become necessary during the construction process. For vessels working on the project, hull and machinery insurance, as well as protection and indemnification insurance, are important. Cargo transportation insurance may also be required for transported materials.

During the operational period, the physical existence of the artificial island, its machinery and facilities, and risks such as loss of revenue, business interruption, terrorism, sabotage, cyber attacks, and natural disasters can be insured with separate policies. It is important to carefully examine whether the policies exclude coverage for storms, waves, sea level rise, ground subsidence, corrosion, and environmental cleanup costs.

Since a fixed artificial island itself is not considered a vessel, the provisions of classic marine insurance may not apply directly. Therefore, the subject of insurance and the risks should be clearly, in detail, and project-specifically defined in the policy.

E. Port, Logistics and Commercial Business Activities

Artificial islands can be used as ports, container terminals, free zones, energy centers, or logistics hubs. This gives rise to relationships involving berthing, loading, unloading, storage, terminal services, pilotage, towing, and agency services.

Establishing a port on an artificial island does not grant it the status of a natural island. However, the port operation becomes subject to national port, customs, security, environmental, and labor legislation. The legal status of vessels arriving at the port requires a combined assessment of both flag state and port state authorities.

Determining the competent court for a commercial dispute arising on an artificial island can also present difficulties. The maritime area where the structure is located, the scope of the coastal state's jurisdiction, the nationalities of the parties, the flag of the vessel, and the choice of law in the contract must all be considered together.

VIII. Legal and Criminal Responsibility

The construction and operation of artificial islands are complex projects involving numerous actors. The state, the main contractor, subcontractors, engineering companies, ship operators, insurers, and financial institutions may all have different responsibilities.

In terms of damages arising from construction defects, the contractor's liability for defects and lack of diligence under the contract for work comes into play. Design errors may give rise to the liability of the engineering or project company; defective materials may give rise to the liability of the manufacturer or supplier. The liability of administrative authorities that fail to adequately fulfill their supervisory duties may be assessed according to the public liability rules of the relevant national law.

If artificial island activities cause harm to another state or its citizens, the state may also be held internationally liable. The state can be held responsible not only for the actions of its own organs but also for its failure to adequately regulate and supervise risky activities carried out by private individuals. In this context, the duty of due diligence includes obligations to grant permits, conduct environmental impact assessments, supervise, share information, and take emergency response measures.

Criminal law and maritime security regulations may apply to attacks, sabotage, terrorist acts, or unlawful seizures of artificial islands. Permanently anchored platforms on the seabed are specifically addressed in international regulations concerning the prevention of unlawful acts against the safety of navigation at sea. Certain actions against fixed platforms may, under certain conditions, create an obligation for the relevant states to prosecute or extradite the perpetrators.

IX. Artificial Islands in Turkish Law

A. Constitutional and Public Status

According to Article 43 of the Constitution of the Republic of Turkey, coastlines are under the sovereignty and control of the state. Public interest shall be given priority in the utilization of coastlines, lake shores, and river shores. This constitutional approach restricts the transformation of coastlines and related reclaimed areas into private property.

The Coastal Law No. 3621 also stipulates that coasts are under the sovereignty and control of the state, and that public interest shall be the primary consideration in the utilization of coasts. According to Article 7 of the law, in cases where public interest so requires, land can be acquired by filling in and draining the sea, in accordance with the implementation zoning plan decision. These operations require consideration of ecological characteristics and completion of the planning and approval processes stipulated in the legislation. Lands acquired through filling in and draining remain under the sovereignty and control of the state and cannot be subject to private ownership.

Therefore, in Turkish law, it is generally not possible to directly establish land ownership in favor of private individuals on an artificial island created by land reclamation. The right of use for private individuals can be granted through allocation, lease, operating rights, easement, or other legal means permitted by the relevant public property regime.

B. Zoning, Permits and Environmental Impact Assessment

Artificial island or large-scale land reclamation projects cannot be implemented solely based on a building permit. The determination of the coastline, preparation of the land reclamation development plan, obtaining opinions from relevant ministries and institutions, assessments of maritime transport and navigation safety, environmental impact assessment, and completion of other necessary permit processes are all required.

The Coastal Law allows for the construction of ports, jetties, breakwaters, shipyards, marinas, lighthouses, and other facilities necessary for coastal development, subject to zoning plan approvals. However, the project's suitability for the public interest and its impact on the natural structure of the coastline must also be evaluated.

In projects covered by the Environmental Impact Assessment Regulation, it is not possible to initiate permit, license, and investment procedures without obtaining the necessary EIA decision for the project. Transportation, coastal structures, ports, and similar infrastructure investments are also examined separately in terms of environmental impact assessment.

If the project has an impact on fishing areas, protected areas, aquaculture production areas, cultural and natural heritage sites, or maritime traffic, the permits and opinions of the relevant institutions must also be obtained. The use of the artificial island for military, energy, tourism, or port purposes may alter the specific legislation that will be applied.

C. Conclusion Regarding Territorial Waters and Maritime Jurisdiction Areas

According to Law No. 2674 on Territorial Waters, Turkish territorial waters are part of the territory of Turkey. The law defines the width of territorial waters as essentially six nautical miles; however, it allows for the determination of wider territorial waters in certain seas, taking into account equity and relevant conditions. The determination of baseline boundaries is also within the authority of the executive branch.

An artificial island constructed off the Turkish coast does not automatically expand Türkiye's territorial waters or other maritime jurisdiction areas. The fact that the artificial island is located far from the coast should not result in the measurement of new territorial waters from that point. While a different assessment may be made regarding permanent port facilities, which form an integral part of the port system, independent offshore facilities and artificial islands cannot be treated as part of the natural coastline.

Turkey is not a party to the United Nations Convention on the Law of the Sea. Türkiye's official declarations to the United Nations in 2026 also confirmed its status as a non-party state to the Convention. Therefore, in applying the provisions of the Convention to Turkey, it must be further assessed whether each provision also constitutes international customary law. Nevertheless, fundamental principles such as the principle that artificial islands should not create maritime zones like natural islands, respect for navigation rights, and the protection of the marine environment remain important for Türkiye's application of maritime law.

D. Turkish Commercial Code and Other Liability Regulations

Since fixed artificial islands generally do not meet the definition of a ship in the Turkish Commercial Code, institutions such as registration in the ship registry, ship ownership, ship mortgage, and ship creditor's rights do not directly apply to the artificial island itself. However, the provisions of the Turkish Commercial Code relating to maritime trade may apply to the ships used in the execution of the project.

In cases of pollution from oil and other harmful substances originating from ships or coastal facilities resembling artificial islands, Law No. 5312 on Emergency Response and Compensation for Damages in Cases of Pollution of the Marine Environment by Oil and Other Harmful Substances may be applicable, depending on the nature of the incident. This law regulates the principles of response, preparedness, and compensation for damages related to pollution from ships and coastal facilities. Whether the artificial island facility falls within the scope of a "coastal facility" should be evaluated based on the nature of the project and the definitions in the law.

X. Contractual Arrangements and Dispute Prevention in Artificial Island Projects

Because artificial island projects are costly, time-consuming, and technically complex, contracts need to be meticulously prepared. The agreements should primarily regulate the rights to use the maritime area, who is responsible for obtaining permits, and the consequences if public authorities refuse permission.

The contract must clearly specify the technical scope of the project, seabed surveys, source of fill material, environmental standards, delivery dates, payment system, price increases, currency fluctuations, tax liabilities, and penalties for delays. Storms, extreme wave movements, war, embargoes, closure of sea routes, delays in permits, and legislative changes should be addressed in detail under force majeure or adaptation provisions.

The limitation of the contractor's liability should include specific provisions regarding indirect damages, loss of revenue, environmental damage, and third-party claims. Whether limitations of liability apply in cases of environmental pollution, gross negligence, and intent should be assessed according to the applicable law.

Insurance obligations should be defined not only by specifying policy names, but also by indicating coverage limits, deductibles, additional insured parties, recourse rights, and policy duration. Responsibility for dismantling, removal, environmental restoration, and seabed restoration in the event of the structure's cessation of use should also be determined from the outset.

In projects involving a foreign element, the applicable law, the competent court or arbitration venue, the language of the contract, the method of notification, and the enforcement of decisions must be clearly agreed upon. In contracts where the state or a public institution is a party, the risks of state immunity, expropriation, revocation of the license, and termination of the contract on grounds of public interest must be regulated separately.

XI. Conclusion

Artificial islands have become an important tool in the modern maritime economy and coastal engineering. However, their large scale and continuous appearance as land do not grant them the status of natural islands. In international maritime law, artificial islands are not geographical features that create maritime jurisdiction, but rather man-made structures where the coastal state exercises specific powers.

Artificial islands do not have their own territorial waters, exclusive economic zones, or continental shelves. They cannot be considered as coastal points in maritime delimitation. While a coastal state may have exclusive rights, particularly regarding the construction and operation of artificial islands in its exclusive economic zone and continental shelf, it must exercise these rights while respecting the rights of other states regarding navigation, flights, and the laying of cables and pipelines.

The security zones created around artificial islands do not constitute a new area of ​​sovereignty. The purpose of these zones is to ensure the security of the facility and maritime traffic. Artificial islands must not obstruct recognized waterways, must be marked, shown on nautical charts, and removed to the necessary extent when their use ends.

From the perspective of maritime law, a fixed artificial island is generally not considered a ship. However, the construction and operation of artificial island projects bring to the forefront many institutions of maritime law, such as ship charter and transportation contracts, towage, port services, collision, marine insurance, environmental liability, and the liability of the ship operator. Therefore, the legal status of the artificial island and the legal regime of shipping and commercial activities around it should be examined separately.

Under Turkish law, coastlines and areas reclaimed through landfill are under the control and disposition of the state. Artificial islands or reclaimed areas cannot be subject to private ownership; any rights granted to private individuals over these areas can only be established within the framework of the public property regime and relevant legislation. The implementation of the project requires a comprehensive consideration of zoning plans, coastal legislation, environmental impact assessments, maritime safety, and sectoral permits.

In conclusion, artificial islands are not a tool for expanding the sovereignty of states; rather, they are engineering structures whose construction, use, and removal are subject to intense public oversight. The legal regime for artificial islands is based on establishing a fair balance between the economic and security interests of the coastal state and the interests of the international community regarding navigation, the environment, and the common use of the seas.