Maritime Boundaries on National Ocean Service Nautical Charts

The National Ocean Service (NOS) is responsible for charting the Nation's coastal waters and, therefore, is the lead Agency for the portrayal of maritime limits of the United States of America. The 1958 Geneva Convention on the Territorial Sea and the Contiguous Zone states " ... the normal baseline for measuring the breadth of the territorial sea is the low waterline along the coast as marked on large-scale charts officially recognized by the coastal state." In 1976, NOS was requested to show various maritime limits on its regular issue of nautical charts. The paper presents the history of maritime boundaries on National Ocean Service (NOS) charts, methods used in constructing the various maritime limits, the definition of the limits, the push for lateral seaward boundaries, and the technical aspects of maritime limits.