Coastal Services Center

U.S. Marine Cadastre

The U.S. Marine Cadastre is an information system, encompassing both the nature and spatial extent of interests in property, value and use of marine areas. Marine or maritime boundaries share a common element with their land-based counterparts in that, in order to map a boundary, one must adequately interpret the relevant law and its spatial context. Marine boundaries are delimited, not demarcated, and generally there is no physical evidence of the boundary. As a result, there can be confusion, disagreement, and conflicting versions of marine boundaries. This Web site will serve as a communication tool to assist Federal and State agencies in rectifying these issues.

Maritime Zones: The boundaries to these zones delimit the extent of a nation's sovereignty, exclusive rights, jurisdiction and control over the maritime areas off its coast. The boundaries may include a 12 nautical mile territorial sea, a 24 nautical mile contiguous zone, a 200 nautical mile Exclusive Economic Zone and the continental shelf. The boundaries of the U.S. Maritime Zones are depicted on official U.S. nautical charts produced and maintained by the U.S. DOC National Oceanic and Atmospheric Administration (NOAA).

U.S. Seabed and Subsoil Boundaries: Submerged Lands Act (SLA); Outer Continental Shelf Act (OCSLA): These U.S. federal and state-level boundaries implement the Submerged Lands Act (43 U.S.C. Sect. 1301 et seq. ) and the Outer Continental Shelf Lands Act (43 U.S.C. Sect. 1331 et seq.)/ The U.S. DOI Minerals Management Service (MMS) is the implementing agency for these Acts and the corresponding boundaries.

Other U.S. Marine Boundaries: U.S. boundaries in marine environment and interests that are Federal as opposed to state are discussed here. Many U.S. agencies are involved in the development and maintenance of these boundaries.

Depiction of U.S. Marine Boundaries: (Click on the image below to view the full graphic and boundary explanations.)