Expenditures from the special fund provided for in Section 45-24-242.12 shall be made exclusively for the purpose of construction, improvement, and maintenance of public highways and bridges including administrative expenses in connection therewith, the retirement of securities evidencing obligations incurred for payment of costs of any construction, improvement, and maintenance, the matching of federal or state funds in the construction of improved roads and bridges in the county in the same manner as other county funds are used to match federal and state funds and for payment of the costs incurred in the administration and the enforcement of this part.