Fla. Stat. § 7.31
The boundary lines of Indian River County are as follows: Beginning at the northwest corner of township thirty-one south, of range thirty-five east; thence east on the line dividing the townships thirty and thirty-one south, to the point where said line intersects the thread of the south fork of the St. Sebastian River; thence northerly down the thread of said stream to the main stream of the St. Sebastian River; thence down the thread of the St. Sebastian River to its confluence with the Indian River; thence east to the intersection with the southwesterly extension of the centerline of the approach channel to the Sebastian Inlet from the Indian River; thence northeasterly along said centerline and continue northeasterly and easterly along the centerline of the Sebastian Inlet to the Atlantic Ocean; thence southward along the Atlantic coast, including the waters of the Atlantic Ocean within the jurisdiction of the State of Florida to the intersection of said Atlantic coast and a line lying 45.22 feet south of, as measured at right angles to, the township line dividing townships thirty-three and thirty-four south; thence west, parallel with, and 45.22 feet south of said township line, to the west right-of-way line of State Road A1A; thence northwesterly along said right-of-way line to the intersection of said right-of-way line and the north line of Lot 25, plat of Kansas City Colony, as recorded in Plat Book 4, page 23, of the public records of St. Lucie County, Florida. Said north line of Lot 25 lying 150 feet north of, and parallel with, as measured at right angles to, the township line dividing townships thirty-three and thirty-four south; thence west along the north line of said Lot 25 to the easterly mean high water line of Round Island Creek; thence meandering southeasterly along said mean high water line to its intersection with the township line dividing townships thirty-three and thirty-four south; thence west on said township line to range line dividing ranges thirty-five and thirty-six east; thence north between ranges thirty-five and thirty-six east to the northeast corner of section one, township thirty-three south, range thirty-five east; thence west on township line dividing townships thirty-two and thirty-three south, range thirty-five east to the range line dividing ranges thirty-four and thirty-five east; thence north on said range line to the northwest corner of township thirty-one south, range thirty-five east, being the place of beginning.
Fla. Stat. § 7.31