The Atlanta City Council adopted an ordinance (24-O-1690) to amend the 1982 Atlanta Zoning Ordinance by modifying Section 16-26.003, 'Conditions of granting a variance', and creating new sections 16-26.008 and 16-20.003(f). These amendments introduce new provisions for administrative zoning setback variances and general variances specifically for the preservation of mature trees. The ordinance allows for variances to reduce required setbacks to protect mature trees (8 inches or more caliper diameter for board-granted variances, 6 inches or more diameter at breast height for administrative variances) that would otherwise be lost due to construction. Such variances require certification from the City Arborist. If a preserved tree dies despite the variance, a replacement plan is required. Administrative variances are permitted on single-family or two-family residential lots, reducing side yard setbacks by up to 50%, provided the City Arborist recommends it. However, administrative variances are prohibited in historic or cultural conservation districts. The Urban Design Commission can grant similar variances in Historic or Landmark Districts.