S.D. Codified Laws § 49-39-2
Any consumers power district issuing revenue debentures, notes, warrants, bonds or other evidences of indebtedness is specifically authorized and empowered to pledge all or any part of the revenues which the district may derive from the sale of electrical energy or other service as security for payment of the principal and interest thereon. Any pledge of revenues shall be made by the directors of the district by resolution or by agreement with the purchasers or holders of revenue debentures, notes, warrants, bonds or other evidences of indebtedness. Any pledge of revenues made by a consumers power district pursuant to this chapter is valid and binding from the date the pledge is made and creates a perfected security interest in the revenues pledged. The revenues pledged and held or thereafter received by the consumers power district or any fiduciary are immediately subject to the lien of the pledge without physical delivery or further act, and the lien of the pledge is valid and binding against all parties having claims of any kind in tort, contract or otherwise against the entity, without regard to whether the parties have notice thereof. Neither resolution or agreement with the purchasers or holders of revenue debentures, notes, warrants, bonds or other evidences of indebtedness by which a pledge is created nor any financing statement, continuation statement, or other instrument relating to the pledge are required to be filed or recorded in any manner.
SDCL 49-39-2