Geography
The Concept of Territorial Waters and Exclusive Economic Zones
Quick fact
Over 40% of the world's oceans are enclosed within Exclusive Economic Zones, giving coastal nations rights to 90% of global fish catch and vast offshore oil and gas reserves.
Why this is interesting
You’re enjoying a beach vacation, but did you know that the ocean beyond the waves is carved up like a giant real estate map? How far off the coast can a country truly claim as its own?
Read the full explanation
Understanding The Concept of Territorial Waters and Exclusive Economic Zones
Imagine a country as a house with a yard. Territorial waters are like the fenced-in backyard—the country has full ownership and control, including the air above and the seabed below. This zone extends 12 nautical miles (about 22 kilometers) from the coast. Ships from other nations can pass through peacefully, but the country can enforce its laws. Beyond that, the Exclusive Economic Zone (EEZ) is like a large, private fishing and mining claim. It stretches another 188 nautical miles, for a total of 200 nautical miles from the coast. In the EEZ, the coastal nation has exclusive rights to natural resources—fish, oil, natural gas, and minerals—but must allow ships and aircraft to pass freely. Both zones are measured from a 'baseline,' usually the low-water line along the coast. These rules are set by the United Nations Convention on the Law of the Sea (UNCLOS), a treaty that nearly every country has signed.
A deeper explanation
The concept of territorial waters and EEZs emerged from centuries of custom and conflict, codified in the 1982 UNCLOS. The rationale is balance: coastal states need security and resource benefits close to shore, while the global community needs freedom of navigation and trade. Territorial waters grant full sovereignty, akin to land territory, including the right to regulate entry, enforce customs, and even block all passage in extreme cases (though 'innocent passage' is guaranteed). The EEZ, however, is a functional zone—sovereignty is limited to resource exploitation and economic activities. The underlying principle is that the coastal state is best positioned and most reliant on these adjacent ocean resources. This system prevents a 'wild west' in the oceans, but also creates disputes, such as overlapping claims (e.g., South China Sea). Understanding this framework helps explain why islands, even tiny ones, can generate enormous economic zones, and why nations fiercely protect their maritime boundaries. The concept matters because it governs access to about 75% of the world's offshore oil reserves and most commercial fisheries, directly impacting global food security and energy politics.