Each municipality with shorelands along significant river segments, as identified in section 437, shall review the adequacy of the zoning on these shorelands to protect the special values cited for these river segments by the former Department of Conservation's 1982 Maine Rivers Study and for consistency with the guidelines established under section 445. Prior to December 15, 1984, each such municipality shall certify to the Board of Environmental Protection either that its existing zoning for these areas is at least as restrictive as the guidelines established under section 445, or that it has amended its zoning for this purpose. This certification must be accompanied by the ordinances and zoning maps covering these areas. Failure to accomplish the purposes of this section results in adoption of suitable ordinances for these municipalities, as provided for in section 438‑A.   [PL 2013, c. 405, Pt. D, §16 (AMD).]