This section sets Louisiana’s gulfward boundary and defines the coastline and related geographic terms.
TITLE 49. STATE ADMINISTRATION CHAPTER 1. GENERAL PROVISIONS PART I. STATE WATER BOUNDARIES §1. Gulfward boundary A. The historic gulfward boundary of the state of Louisiana extends a distance into the Gulf of America three marine leagues from the coastline. For the purposes of this Part, "three marine leagues" is equal to nine geographic miles or 10.357 statute miles. B. The coastline of Louisiana shall be the line of ordinary low water along that portion of the coast which is in direct contact with the open sea and the line marking the seaward limit of inland waters, and shall be not less than the baseline defined by the coordinates set forth in United States v. Louisiana, 422 U.S. 13 (1975), Exhibit "A". Under no circumstances shall the coastline of Louisiana be nearer inland than the baseline established by such coordinates. C. No provision of this Section shall be construed to relinquish any dominion, sovereignty, territory, property, or rights of the state of Louisiana or its political subdivisions otherwise provided by law. D. Any reference in the codified or uncodified laws of this state to the "Gulf of Mexico" shall be deemed to refer to the "Gulf of America", as designated by the United States Board on Geographic Names. This Subsection shall apply to all existing statutes, regulations, administrative rules, contracts, and other legal instruments, and shall be given full force and effect in all official state documents and proceedings. Amended by Acts 1954, No. 33, §1, eff. June 21, 1954; Acts 2011, No. 336, §1; Acts 2025, No. 105, §2, eff. June 8, 2025.