An ordinance of the Mayor and City Council is required to:designate any area as a Historical and Architectural Preservation District; designate any area as a Historical Conservation District; modify the boundary lines of an existing Historical and Architectural Preservation District; or modify the boundary lines of an existing Historical Conservation District. The ordinance must be supported by written findings of fact that the proposed Preservation District or Conservation District and its boundaries will comply with:the requirements for Local Government Certification under the National Historic Preservation Act (16 U.S.C., Chapter 1A, Subchapter II); the Secretary of the Interior’s Standards for Identification and Registration; and the Commission’s own Historic Preservation Procedures and Guidelines. City Code, 1976/83, art. 1, §40(j)(1), (4) 2000, art. 6, §3-1(a), (b), (d) Ord. 64-229 Ord. 67-939 Ord. 76-022 Ord. 99-547 Ord. 04-672 Ord. 15-408