S.D. Codified Laws § 31-26-6
Whenever the erection and maintenance of electric lines shall, by reason of negligence in the construction or operation of such lines, cause inductive interference in grounded lines, the owner of the electric lines shall furnish all necessary wire and attachments for making telephone lines metallic, where necessary, and such additional poles above the number in place as is necessary to carry the additional telephone equipment in accordance with standard practices, and shall pay the cost of any necessary moving of telephone lines. The burden of proof of negligence in the construction or operation of such electric lines shall be upon the telephone company complaining of such interference. In the absence of negligent construction or operation the owner of the electric lines shall not be liable for any inductive interference caused in grounded lines. But the owner of electric lines shall be liable for all inductive interference in metallic lines or cables that are properly constructed.
SDCL 31-26-6