33 U.S.C. § 151
Section 151 · High seas and inland waters demarcation lines
Amended 4 times on record
Applied in 26 court decisions — leading case United States v. Louisiana (1960)
Most recently applied in United States v. Jhonathan Alfonso (June 2024)
How often courts cite this section
Court decisions citing this, by year.Markers show enactment, consequential amendments, and circuit splits over this section — watch for a citation surge after a change or a disagreement. The dip in the last several years is a data-coverage gap, not a real trend — our corpus holds fewer opinions from the most recent years, so recent citations are undercounted.
The Secretary of the department in which the Coast Guard is operating shall establish appropriate identifiable demarcation lines dividing the high seas from harbors, rivers, and other inland waters of the United States, for the purpose of determining the applicability of special navigational rules in lieu of the International Regulations for Preventing Collisions at Sea.
The Secretary shall also establish appropriate identifiable lines dividing inland waters of the United States from the high seas for the purpose of determining the applicability of each statute that refers to this section or this section, as amended. These lines may not be located more than twelve nautical miles seaward of the base line from which the territorial sea is measured. These lines may differ in position for the purposes of different statutes.
For the purposes of this section, the term “United States” includes the several States of the United States, the District of Columbia, the Commonwealth of Puerto Rico, Guam, American Samoa, the United States Virgin Islands, the Commonwealth of the Northern Mariana Islands, the Trust Territory of the Pacific Islands, and any other Commonwealth, territory, or possession of the United States.
Editorial notes U.S. Code · Office of the Law Revision Counsel
References in Text
The International Regulations for Preventing Collisions at Sea, referred to in subsec. (a), are set out in Appendix A to Part 81 of Title 33, Code of Federal Regulations.
Codification
Section was not enacted as part of act June 7, 1897, ch. 4, 30 Stat. 96, which comprises a major part of this chapter.
Amendments
1980—Subsec. (a). Pub. L. 96–324 designated existing provisions as subsec. (a), substituted provision authorizing the Secretary of the Department in which the Coast Guard is operating to establish demarcation lines for provision authorizing the Secretary of the Treasury to establish demarcation lines, and inserted provision specifying the purpose of establishing demarcation lines as determining the applicability of special navigational rules in lieu of the International Regulations for Preventing Collisions at Sea.
Subsec. (b). Pub. L. 96–324 added subsec. (b).
Subsec. (c). Pub. L. 96–591 and Pub. L. 96–376 made identical amendments by striking out reference to the Canal Zone.
Pub. L. 96–324 added subsec. (c).
Termination of Trust Territory of the Pacific Islands
For termination of Trust Territory of the Pacific Islands, see note set out preceding section 1681 of Title 48, Territories and Insular Possessions.
Territorial Sea of United States
For extension of territorial sea of United States, see Proc. No. 5928, set out as a note under section 1331 of Title 43, Public Lands.
Cross References
Vessel bridge-to-bridge radiotelephone requirement and capability for vessels on navigable waters of United States inside lines established under this section, see section 1203 of this title.