Meaning and Juridical Importance
In the law governing oceans and seas, baselines form the very foundation upon which a coastal State’s maritime rights are constructed. A baseline may be understood as the legally recognized line along the coast from which the breadth of various maritime zones is measured. These zones include the territorial sea, the contiguous zone, the exclusive economic zone, and the continental shelf. The fixing of baselines is not a mere technical exercise; rather, it determines the spatial reach of State authority at sea and has direct implications for sovereignty, jurisdiction, navigation, and access to marine resources. The contemporary legal regime relating to baselines is codified under the United Nations Convention on the Law of the Sea (UNCLOS), which seeks to harmonize the rights of coastal States with the collective interests of the international community.
Normal Baseline
The normal baseline represents the general rule for the measurement of maritime zones. It is based on the low-water line along the coast, as depicted on officially recognized nautical charts of the coastal State. This method is particularly suitable where the coastline is comparatively even and does not exhibit extreme geographical irregularities. By following the natural contour of the coast at low tide, the normal baseline reflects geographical reality and provides a predictable and objective reference point. Its simplicity and reliance on observable coastal features make it the preferred method under international law, reducing the scope for disputes between States.
Straight Baseline
There are, however, coastal regions where the physical geography makes reliance on the low-water line impractical or misleading. Coastlines that are deeply indented, highly irregular, or accompanied by a fringe of islands close to the shore present special challenges. In such situations, international law permits the adoption of straight baselines, which are drawn by connecting selected points along the coast. This approach allows the coastal State to account for its distinctive geographical conditions while determining its maritime limits. Nevertheless, the use of straight baselines is subject to important legal constraints. They must broadly follow the general direction of the coast, and the waters enclosed by them must maintain a close geographical and functional connection with the land territory.
The acceptability of straight baselines in international law was authoritatively confirmed in the Anglo-Norwegian Fisheries Case. In that case, the International Court of Justice recognized that Norway’s unique coastal configuration justified departure from the normal baseline method. The Court emphasized that international law must be applied with due regard to geographical realities and long-standing practices, provided they are reasonable and consistent with legal principles.
Archipelagic Baseline
A distinct and specialized form of baseline exists for archipelagic States. These are States composed entirely of one or more archipelagos and whose geographical identity is inseparably linked with the surrounding waters. Under UNCLOS, such States are entitled to draw archipelagic baselines by joining the outermost points of the outermost islands and reefs of the archipelago. The waters enclosed within these baselines are designated as archipelagic waters and fall under the sovereignty of the archipelagic State. This regime acknowledges that, for archipelagic States, the sea is not merely a separating element but an integral component of national territory.
At the same time, the law of the sea ensures that global navigational interests are not compromised. Accordingly, other States enjoy specific passage rights through designated sea lanes within archipelagic waters, preserving the continuity of international maritime and aerial navigation.
Legal and Practical Significance of Baselines
Baselines play a decisive role in shaping the maritime entitlements of coastal States. By determining the outer limits of maritime zones, they influence control over fisheries, offshore energy resources, seabed minerals, and strategic sea routes. They also affect the delimitation of maritime boundaries between neighboring States and often lie at the heart of international disputes concerning overlapping claims. From a broader perspective, baselines serve as the legal bridge between land territory and maritime space, ensuring that the exercise of coastal State rights remains anchored in both geography and law.
