Ohio Rev. Code § 5531.02
The general assembly assents to the act of congress, approved July 11, 1916, entitled "An act to provide that the United States shall aid the states in the construction of rural post roads, and for other purposes," thirty-ninth United States statutes at large, page 355, and the emergency relief appropriation act of 1935, approved April 8, 1935, and all acts amendatory thereof and supplemental thereto, and other acts providing funds for the same or similar purposes.
The department of transportation may enter into all contracts and agreements with the United States, relating to the construction and maintenance of rural post roads under such act, and submit such programs of construction and maintenance as required by the federal government and do all other things necessary to carry out the co-operation contemplated and provided by such acts and amendments. The good faith of the state is pledged to make available funds sufficient for any biennium, to enable the state or its political subdivisions to comply with the requirements of the federal government concerning the sums apportioned to the state by the United States during each of the years for which federal funds are appropriated by such acts, to maintain the roads constructed under such acts, and to make adequate provisions for carrying out such maintenance. All moneys accruing to the highway fund and available for expenditure in the construction and maintenance of highways, and all federal funds apportioned to this state for the highway improvement purposes under such acts of congress, shall be expended upon the highways comprising the state highway system, or upon the extension of such highways into or through municipal corporations, except that where funds are allocated to this state from any appropriations made by congress for such purposes, and which allocation provides that a fixed per cent shall be expended upon secondary roads, including United States post roads, school bus routes, and farm-to-market roads, such percentage allocated by federal legislation shall be expended upon secondary or feeder roads as defined by federal law or ruling by any federal agency pursuant to law. The director of transportation shall not request the federal government to reduce the percentage of the apportionment to this state for expenditure on secondary or feeder roads. Such expenditures shall be equitably expended in the several counties of the state. The director may use department equipment under his jurisdiction and charge the cost and expense incident to such use to the fund from which the other costs of the work are paid to carry out the purposes of sections 5531.02 to 5531.04 of the Revised Code, and to comply with the requirements of the federal government, and any road or street funds that are to the credit of the county, township, or municipal corporation in which the proposed improvement is to be made, may be used in such proportion as is agreed upon between the director and the board of county commissioners, or the board of township trustees, or the legislative authority of a municipal corporation for the purpose of supplementing federal funds. The board of county commissioners or legislative authority of a municipal corporation may assume such proportion of the cost of an improvement under its respective jurisdiction as available funds will permit.
R.C. § 5531.02