S.D. Codified Laws § 10-10-8
The county commissioners at the regular annual equalization meeting, shall consider the classification made pursuant to § 10-10-5, together with the value placed upon each tract of land and the value of the improvements thereon, and may, for good cause shown, change such classification and value thereon as may be just, and shall make such equalization thereof between the various townships as is now provided by law therefor. The valuations placed upon such lands shall become the basis for taxation purposes subject only to any change that may be made under the law by the Office of Hearing Examiners in equalizing property valuations between the different classes of property in the various counties of the state. However, the Office of Hearing Examiners may not in any way raise the total valuation of such property within the state.
SDCL 10-10-8