The offshore areas of a country have been divided into 3 zones: 1. Territorial Sea 2. Exclusive Economic Zone 3. High Sea.
Zone # 1. Territorial Sea:
The shore and coastlines of a coastal country are seldom straight rather are crenulated and indented. The imaginary line joining the land projecting towards the sea is called baseline (fig. 31.1). Sea water lying between coastland and base line is called internal water which is never contiguous.
The seaward water from the coastland of a nation is called territorial sea the distance of which is measured from the base line generally up to 12 nautical miles towards the sea. In the beginning, the seaward limit of territorial sea was determined as 3 miles (4.8 km) but now generally the limit of territorial sea of different nations has been determined differently e.g. Latin American countries have determined the limit of their territorial sea as 320 km (200 miles) while the USA accepts 4.8 km (3 miles) as the seaward limit of the territorial sea.
Territorial sea has been variously named as marine belt, marginal sea etc. The coastal nation has the right of its sovereignty over its territorial sea and has the full and exclusive right of its use. No other country can enter the territorial sea of a country without the permission of the concerned country. The continuous portion of the sea beyond the seaward limit of territorial sea up to a distance of 12 nautical miles is called contiguous zone (fig. 31.1) in which the concerned coastal country commands limited exclusive rights.
It may be mentioned that the seaward limit of the contiguous zone is 24 nautical miles from the base line. The concerned coastal nation has the rights of custom duties, fiscal, strategic, defence, immigration and sanitary regulations within the territorial sea and contiguous zone and also enjoys the right to punish the concerned parties for the infringement of these regulations.
Zone # 2. Exclusive Economic:
Exclusive Economic Zone extends up to a distance of 200 nautical miles from the base line. The concerned coastal state has the exclusive right of the survey, exploitation, conservation and management of mineral resources of ocean deposits, ocean floor (crust), marine water energy, water and marine organisms within this exclusive economic zone (EEZ).
No other country can venture in any economic activity (e.g., fishing, mining etc.) in this zone without the permission of the concerned coastal state but this zone is open for laying down submarine cables, navigation of ships, flying of aeroplanes for other states. It may be pointed out that such rights are enjoyed by other states only outside the seaward limit of the territorial sea.
Zone # 3. High Sea:
High Sea extends beyond the seaward limit of the exclusive economic zone and includes the vast oceanic areas. All the countries have equal rights of navigation, aviation, fishing, mining, laying down of submarine cables, scientific researches, exploration etc.