The delimitation of maritime boundaries

In many parts of the world, the maritime zones (territorial sea, contiguous zone, exclusive economic zone (EEZ) and continental shelf) of neighbouring States overlap. If conflicts over resource exploitation and other activities in areas of overlap are likely, it will be desirable for the States concerned to establish a boundary between their overlapping zones, whether by negotiation, with the aid of a mediator or conciliation commission, or by recourse to arbitration or an international court. The UN Convention on the Law of the Sea provides limited guidance as to how such boundaries are to be delimited, especially boundaries between overlapping EEZs and continental shelves. Greater guidance has been provided by international courts and arbitral tribunals. The chapter begins by explaining the possible processes by which a maritime boundary may be established. It then analyses the relevant provisions of the Convention and the now substantial body of case law on maritime boundary delimitation. It also examines possible alternatives to a maritime boundary, such as a zone of joint management, as well as the obligations of restraint to which States are subject where there is no boundary or agreed alternative arrangement. Finally, the possible consequences of predicted sea-level rise for existing maritime boundaries are explored.