S.D. Codified Laws § 31-19-60
If the Department of Transportation or any board of county commissioners determines that any lands taken by condemnation proceedings or acquired as public use easements are no longer required for use in constructing or repairing public highways, the Transportation Commission or the board shall adopt a resolution to that effect and such lands shall revert to their former owner or his assigns. The Department of Transportation may sell and dispose of any lands acquired by gift, devise, or purchase in which fee ownership was obtained and which is no longer needed for the purpose it was acquired. The land shall be sold in the same manner set forth by § 31-2-27. However, an abutting landowner shall have the first opportunity to purchase any right-of-way to the center of the right-of-way at its appraised value. No reversion, sale, or disposition of any highway as provided in this chapter may diminish any existing right of use enjoyed by any public utility, municipally-owned utility, or cooperative utility which provides electricity, gas, water, or telephone service.
SDCL 31-19-60