S.D. Codified Laws § 41-17-6
The Game, Fish and Parks Commission may pledge park license receipts and any revenues derived from the operation of any recreational facility constructed with income derived from the issuance of the bonds authorized pursuant to § 41-17-5 as security for any bonds issued under § 41-17-5. If any existing recreational facility is reconstructed, reequipped, refurnished, or otherwise improved with income derived from the issuance of revenue bonds, the value of the original facility and the value of the improvement shall be appraised and fixed. All revenue derived from the facility and the improvement shall be apportioned on the basis of the value of the original facility and the value of the improvement. Only that portion of the revenue representing the amount that the improvement bears to the whole may be pledged as security for any bonds issued under § 41-17-5.
SDCL 41-17-6