S.D. Codified Laws § 31-12-14
If the cost of any road, bridge, tile, or culvert construction, repair work, or materials upon a county highway system or secondary roads exceeds the amount provided for in § 5-18A-14 or any less amount for which work bids are to be called for, and after plans and specifications therefor have been prepared and filed in the office of the county auditor, the board having charge shall designate a time not less than twenty days from the date of such filing, at which sealed bids for such work or materials will be received. The board shall cause notice thereof to be published once each week for two successive weeks in one of the official newspapers of the county. The notice shall state where plans and specifications may be examined, when and where bids will be opened, a brief statement of the principal items of work and materials contemplated by the improvement, and the location of the same, the amount of the certified check or bidder's bond to be required, and such further notice as the board having supervision may deem advisable. Bids may be received at any special or regular meeting of the board. The board may refuse to accept any bids submitted.
SDCL 31-12-14