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Maritime Limits and Boundaries of United States of America

Published by Office of Coast Survey | National Oceanic and Atmospheric Administration, Department of Commerce | Metadata Last Checked: December 18, 2025 | Last Modified: 2020-01-01T00:00:00.000+00:00
NOAA is responsible for depicting on its nautical charts the limits of the 12 nautical mile Territorial Sea, 24 nautical mile Contiguous Zone, and 200 nautical mile Exclusive Economic Zone (EEZ). The outer limit of each of these zones is measured from the U.S. normal baseline, which coincides with the low water line depicted on NOAA charts and includes closing lines across the entrances of legal bays and rivers, consistent with international law. The U.S. baseline and associated maritime limits are reviewed and approved through the interagency U.S. Baseline Committee, which is chaired by the U.S. Department of State. The Committee serves the function of gaining interagency consensus on the proper location of the baseline using the provisions of the 1958 Convention on the Territorial Sea and the Contiguous Zone, to ensure that the seaward extent of U.S. maritime zones do not exceed the breadth that is permitted by international law. In 2002 and in response to mounting requests for digital maritime zones, NOAA launched a project to re-evaluate the U.S. baseline in partnership with other federal agencies via the U.S. Baseline Committee. The focus of the baseline evaluation was NOAA's largest scale, most recent edition nautical charts as well as supplemental source materials for verification of certain charted features. This dataset is a result of the 2002-present initiative and reflects a multi-year iterative project whereby the baseline and associated maritime limits were re-evaluated on a state or regional basis. In addition to the U.S. maritime limits, the U.S. maritime boundaries with opposite or adjacent countries as well as the US/Canada International Boundary (on land and through the Great Lakes) are also included in this dataset.

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NGDA National Geospatial Data Asset Water Oceans and Coasts Theme NGDAID167 OceanCommunity Marine Boundaries Nautical Charting Alabama Alaska American Samoa Baker Island California Commonwealth of the Northern Mariana Islands Delaware Florida Georgia Guam Hawaii Howland Island Jarvis Island Johnston Atoll Kingman Reef Louisiana Maine Maryland Massachusetts Mississippi New Hampshire New Jersey New York North Carolina Oregon Palmyra Atoll Puerto Rico Rhode Island South Carolina Texas U.S. Virgin Islands Virginia Wake Island Washington Boundary Contiguous Zone Exclusive Economic Zone Federal Register, Vol 60, No. 163, August 23, 1995 GIS ICJ Judgment, Gulf of Maine, 1984 International Boundary Commission Law of the Sea Limit Maritime Polyline Presidential Proclamation No. 5030, March 1983 Presidential Proclamation No. 5928, December 1988 Presidential Proclamation No. 7219, August 1999 Territorial Sea US/Cook Islands Maritime Boundary Treaty, 1980 US/Cuba Maritime Boundary Agreement, 1977 US/Japan Exchange of Notes, 1994 US/Mexico Maritime Boundary Treaty, 1970 US/Mexico Maritime Boundary Treaty, 1978 US/New Zealand (Tokelau) Maritime Boundary Treaty, 1980 US/Niue Maritime Boundary Treaty, 1997 US/Russia Maritime Boundary Agreement, 1990 US/UK (Anguilla) Maritime Boundary Treaty, 1993 US/UK (British Virgin Islands) Maritime Boundary Treaty, 1993 US/Venezuela Maritime Boundary Treaty, 1978 DOC/NOAA/NOS/OCS > Office of Coast Survey, National Ocean Service, NOAA, U.S. Department of Commerce ocs

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