Authorizes the director of a county planning department to issue a special management area use permit to redevelop permanent affordable multi-family rental housing that has been substantially destroyed as result of certain natural disasters and requires county planning departments and any other applicable state or county department or agency to prioritize approving permits for these redevelopments, with certain exceptions. Exempts permanently affordable multi-family rental housing projects within the special management area that are being redeveloped and are located on properties or districts on the state or national historic register from environmental impact statement requirements. Permits county planning departments and any other applicable state or county department or agency to amend or modify final plans and specifications for redevelopment of an existing experimental and demonstration housing project, with certain restrictions. Effective 7/1/3000. (HD2)