S.D. Codified Laws § 31-22-7
If the right-of-way be laid along the line separating two farms, then the owner of the isolated tract for which such right-of-way was laid shall erect and maintain one-half of the fence along both sides of such right-of-way, but if it be laid through a farm and not along the border thereof, no fence will be deemed necessary unless requested by the owner of land through which such road passes, in which cases the owner of the isolated tract shall erect and maintain the fence along both sides of such right-of-way and shall locate at a point to be described by the owner of the land gates at least sixteen feet wide in each of such fences. But if no fence is requested the owner of such isolated land shall construct, maintain, and keep closed substantial and suitable gates in all fences which such roadway may cross. The laws of this state pertaining to the erection and maintenance of partition fences shall apply to the fencing of such right-of-way wherever not in conflict with this section.
SDCL 31-22-7