Special maritime zones enable coastal States to participate more actively in the protection of the natural environment.
The maritime zones are established by Part V of the UNCLOS Convention (1982). They are illustrated in the diagram below and in the definitions table.

Illustration of the different maritime zones in nautical miles (n)
Two types of zones are particularly important in terms of voluntary discharge of oil:
The French Ecological Protection Zone in the Mediterranean came into effect on 10 January 2004, when an order was published in the Journal Officiel determining the limits of the zone (order n°2004-33 of 8 January 2004). This means that France can prosecute offences connected to marine water pollution outside the 12 nautical mile radius of the territorial waters, and up to 60 nautical miles from the coast, in accordance with the MARPOL Convention.
Having noted a lack of action on behalf of certain flag States, France found a solution in part of the possibilities offered by Marpol and by the United Nations Convention on the Law of the Sea in the domain of the environment, which was included in French legislation. In doing this, France fully devoted itself to one of the convention's obligations, giving each State the obligation to protect the marine environment.
This obligation is aimed first and foremost at punishing vessels which unhesitatingly pollute the water on the boundary of territorial waters. This widening of the governed area offers a new way of protecting the Mediterranean, with a probable gradual increase in the adoption of similar zones by other coastal States.
This new area provides more motivation for aerial observation and facilitates the affirmation of which country is responsible for the protection of an environment which is threatened every time a vessel is caught polluting the sea. Thus the Turkish container ship the Timic, caught polluting by the illicit discharge of oil in the Mediterranean EPZ on 29 January 2004, had to provide a bank guarantee of 300,000 € before being allowed to continue its journey.

Example of shared territories: equal distances between Spain, Italy and France
for the French ecological protection zone (royal blue on the map). Source: Cedre
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