S.D. Codified Laws § 50-6A-39

Except as may be limited by the terms and conditions of any grant, loan, or agreement authorized by §§ 50-6A-27 and 50-6A-28, an authority may by contract, lease, or other arrangements, upon a consideration fixed by it, grant to any qualified person for a term not to exceed thirty years the privilege of operating, as agent of the authority or otherwise, any airport owned or controlled by the authority; provided that no person shall be granted any authority to operate an airport other than as a public airport or to enter into any contracts, leases, or other arrangements in connection with the operation of the airport which the authority might not have undertaken under § 50-6A-38.