Ohio Rev. Code § 6131.40
When the time has passed for the receiving of bids referred to in section 6131.37 of the Revised Code, the county engineer shall, as soon as is practicable, open, read aloud, and tabulate the bids and report them to the board of county commissioners with his recommendation of which bid, or combination of bids, in all respects is the best. No bid shall be accepted after the time designated for receiving bids. The board may accept any combination of bids of different bidders for different parts of the work or for furnishing different materials that they find will be more economical or advantageous than the aggregate bid of a single bidder, but no bid shall be accepted for any part or thing that exceeds the estimate of the engineer unless only by such acceptance can a contract for the completion of an entire improvement be let for less than the aggregate estimate of the total improvement.
If it is found that all bids for work and material, or all bids for any separate part of work and material, are in excess of the estimates reported by the engineer, the board shall order the readvertisement of the same, or any part thereof, for which the bids are in excess, and they may direct the engineer to re-estimate the same for bids on the new estimate.
R.C. § 6131.40