Maritime limits for the United States are measured from the U.S. baseline, recognized as the low-water line along the coast as marked on NOAA's nautical charts in accordance with the articles of the Law of the Sea. The baseline and related maritime limits are reviewed and approved by the interagency U.S. Baseline Committee. The primary purpose of this dataset is to update the official depiction of these maritime limits and boundaries on NOAA's nautical charts. The Office of Coast Survey depicts on its nautical charts the territorial sea (12 nautical miles), contiguous zone (24nm), and exclusive economic zone (200nm, plus maritime boundaries with adjacent/opposite countries).

U.S. maritime limits are ambulatory and subject to revision based on accretion or erosion of the charted low water line. To ensure you are up-to-date and for more information about U.S. Maritime Limits and Boundaries, see http://www.nauticalcharts.noaa.gov/csdl/mbound.htm.

For the full FGDC metadata record, see http://www.ncddc.noaa.gov/approved_recs/nos_de/ocs/ocs/ocs/MB_ParentDataset.html.

Coordinates for the US/Canada international boundary, on land and through the Great Lakes, are managed by the International Boundary Commission. These boundaries are included with this dataset for continuity.