When the work provided for under section 971.12 of the Revised Code is completed to the satisfaction of the board of township trustees, it shall certify the costs to the township fiscal officer. If the costs are not paid within thirty days, the township fiscal officer shall certify them to the county auditor with a statement of the cost of the construction or maintenance and incidental costs incurred by the trustees and a correct description of each piece of land upon which the costs are assessed.