Okla. Stat. tit. 82, § 1611
Within one hundred eighty (180) days after the completion of construction of any flood control protective works, the floodplain board in its area of jurisdiction shall redefine the floodplain as altered by the works. The new floodplain definition and one-hundred-year flood elevations shall then be submitted to the Board.
Laws 1980, c. 179, § 11, emerg. eff. May 13, 1980.