Fla. Stat. § 7.43
The boundary lines of Martin County are as follows: Beginning at the northwest corner of township thirty-eight south, range thirty-seven east; thence east, concurrent with the south boundary line of St. Lucie County, to the southwest corner of section thirty-one, township thirty-seven south, range forty-one east; thence north on the west line of said section thirty-one and section thirty, township thirty-seven south, range forty-one east, 6,459 feet to a point lying within the water body of the north fork of the St. Lucie River; thence departing said line within the north fork of the St. Lucie River a bearing direction (State Plane Coordinate System, Florida East Zone) of 41 degrees north, 4 minutes west, a distance of 6,155 feet, more or less, to a point lying within the water body of the north fork of the St. Lucie River; thence departing said point a bearing direction (State Plane Coordinate System, Florida East Zone) of 45 degrees north, 16 minutes east, a distance of 2,355 feet, more or less, to a point intersecting with the north shore of the north fork of the St. Lucie River and the west edge of the Howard Creek as concurrent with the City of Port St. Lucie municipal boundary limits; thence departing said intersecting shore and edge lines following along the City of Port St. Lucie municipal boundary line north along the west edge of Howard Creek to the south line of the northeast quarter of section twenty-four, township thirty-seven south, range forty east; thence east along said south line of the northeast quarter to the intersection of the east 924.15 feet of section twenty-four, township thirty-seven south, range forty east; thence north along said east 924.15-foot line of section twenty-four, township thirty-seven south, range forty east, to the intersection of the north line of the south 508.15 feet of the northeast quarter of section twenty-four, township thirty-seven south, range forty east; thence east along said south 508.15-foot line of the northeast quarter of said section twenty-four, township thirty-seven south, range forty east, to an intersection with the west line of township thirty-seven south, range forty-one east, also being the existing Martin County boundary line; thence north concurrent with the Martin County boundary line, along the west line of sections nineteen and eighteen, township thirty-seven south, range forty-one east, to the northwest corner of section eighteen, township thirty-seven south, range forty-one east; thence east on the north line of said section eighteen and other sections to the waters of the Atlantic Ocean; thence easterly to the eastern boundary of the State of Florida; thence southward along the coast, including the waters of the Atlantic Ocean within the jurisdiction of the State of Florida, to the south line of section twenty, township forty south, range forty-three east, produced easterly; thence west on the south line of said section twenty, and other sections, to the southwest corner of section twenty-two, township forty south, range forty-two east; thence south on the east line of section twenty-eight, township forty south, range forty-two east, to the southeast corner of said section twenty-eight; thence west on the south line of said section twenty-eight and other sections to the east shore of Lake Okeechobee; thence continue west in a straight course to the northeast corner of section thirty-six, township forty south, range thirty-four east, being the southwest corner of section thirty, township forty south, range thirty-five east; thence northeasterly in a straight course to the line of normal water level on the boundary of Lake Okeechobee at its intersection with the line dividing ranges thirty-six and thirty-seven east, township thirty-eight south; thence north on said range line to the place of beginning.
Fla. Stat. § 7.43