S.D. Codified Laws § 9-4-14
If a municipality operates an airport organized pursuant to Title 50 outside the corporate limits of the municipality, the restrictions of § 9-4-1 against annexation of noncontiguous territory do not apply to the annexation of the airport by such municipality. If the municipality annexes such airport, the municipality may exercise extraterritorial jurisdiction pursuant to chapter 11-6, but only to the extent of one and one-quarter miles of the exterior boundary of the airport property. Such one and one-quarter mile extraterritorial jurisdiction supercedes the three-mile extraterritorial jurisdiction of any other municipality or jurisdiction of any other governmental entity, except as provided in Title 50.
Such one and one-quarter mile extraterritorial jurisdiction does not include property located within the corporate limits of another municipality. However, the latter municipality may not allow any airport hazards as defined in Title 50 in its corporate limits within the one and one-quarter mile extraterritorial jurisdiction around the airport property.
SDCL 9-4-14