An exclusive economic zone (EEZ) is a sea area beyond and adjacent to a coastal state’s territorial sea, extending up to 200 nautical miles from its baseline, where that state has sovereign rights for exploring and exploiting, conserving and managing natural resources, both living and nonliving, of the seabed and subsoil, and within this zone regarding other economic activities such as the production of energy from water, currents, and wind. This enduring ocean regime balances coastal state entitlements with obligations to protect the marine environment and ensure other states’ freedoms, such as navigation and overflight, making the EEZ a central concept in modern ocean governance.
How an EEZ Is Established and Measured
An EEZ originates from the baseline, normally the low-water line along the coast as marked on large-scale charts officially recognized by the coastal state. From this baseline, the breadth of the territorial sea, the contiguous zone, and the EEZ are measured. Where coasts lie close together or a narrow sea divides them, opposite or adjacent states must delimit their maritime zones through agreement to achieve an equitable solution, often guided by the geometry of the coast and international jurisprudence, notably the 1982 United Nations Convention on the Law of the Sea (UNCLOS).
Key Rights Within an EEZ
Within its EEZ, a coastal state holds sovereign rights that are important for resource use and management, but it does not have full territorial sovereignty as it does in its territorial sea. These rights include:
- Exploring and exploiting, conserving and managing natural resources, whether living or nonliving, of the seabed and subsoil.
- Constructing and using artificial islands, installations, and structures for any peaceful purpose, such as energy production or marine research.
- Conducting marine scientific research subject to the coastal state’s consent and oversight.
- Preventing, reducing, and controlling pollution of the marine environment, enforcing laws and regulations under UNCLOS.
Resource Sovereignty
The coastal state’s sovereign rights focus on the economic benefits derived from the zone, particularly fisheries, hydrocarbon and mineral exploration, and marine energy. Other states enjoy freedoms such as navigation and overflight, laying submarine cables and pipelines, subject to the coastal state’s laws and regulations and to the interests of other states.
Installations and Research
States may erect artificial islands and install infrastructure to harness wind, tidal, or wave energy, provided they exercise due care to avoid hazards to navigation and respect the rights of other users. Marine scientific research is encouraged but requires the coastal state’s approval, ensuring that findings support sustainable use and environmental protection.
Duties and Limitations of Coastal States
Holding EEZ rights comes with strict duties. Coastal states must act with due regard to the rights of other states, comply with UNCLOS obligations, and base resource management decisions on the best available scientific evidence. They must also consider the impact of activities on dependent populations, particularly small island developing states and artisanal fishing communities.
Overlapping Claims and Disputes
When maritime zones of states overlap, equitable principles come into play. Disputes may concern the exact location of baselines, the delimitation of the boundary, or alleged breaches of environmental or resource management duties. Many cases have been resolved through negotiation, mediation, or binding arbitration under UNCLOS, while some remain politically sensitive.
Impacts on Industry, Environment, and Governance
The EEZ framework shapes fisheries management, offshore energy projects, seabed mining, and marine conservation. For coastal states, it offers a management arena for sustainable use; for industries, it defines licensing and regulatory regimes; and for the environment, it establishes a legal basis to curb pollution and protect ecosystems. Effective governance within EEZs remains critical for balancing economic development with long-term ocean health.
Quick Reference: Core EEZ Attributes
| Attribute | Verified Detail | Source Type |
|---|---|---|
| Maximum breadth | 200 nautical miles from the baseline | UNCLOS Article 57 |
| Legal basis | Solemm rights for resource exploration, conservation, and management | UNCLOS Part V |
| Other states’ rights | Navigation, overflight, submarine cables and pipelines subject to coastal laws | UNCLOS Articles 87–89 |
| Dispute resolution | Available via negotiation, arbitration, and international judicial bodies | UNCLOS Part XV |
| Environmental obligation | Protect and preserve the marine environment, prevent transboundary harm | UNCLOS Articles 192–197 |
Distinctions to Remember
It is helpful to differentiate the EEZ from adjacent maritime zones:
- Territorial sea: Extends up to 12 nautical miles; coastal state exercises full sovereignty.
- Contiguous zone: Extends up to 24 nautical miles from baseline; coastal state may enforce customs, fiscal, immigration, and sanitary laws.
- EEZ: Extends to 200 nautical miles; coastal state holds sovereign rights for resource purposes while other states retain certain freedoms.
- High seas: Beyond national jurisdiction; open to all states, with freedoms of navigation, overflight, and fishing, governed by international law.
FAQ
Reader questions
Can another state drill for oil in my EEZ?
No. While other states enjoy freedoms such as navigation and overflight, the coastal state holds the exclusive right to authorize drilling for oil and gas within its EEZ. Outside the EEZ, on the high seabed area beyond national jurisdiction, any state may pursue deep-sea mining under an International Seabed Authority regime.
Does an EEZ extend over water column and seabed?
Yes. An EEZ encompasses both the water column above the seabed and the seabed itself, allowing the coastal state to manage living and nonliving resources throughout that column and subsoil.
Are EEZs permanent once established?
EEZs are stable unless delimitation agreements or judicial decisions adjust boundary lines. Baseline definitions can evolve with new mapping technologies and confirmations, but the 200-nautical-mile breadth is fixed unless modified by agreement.