All contracts for the construction, improvement or repair of a road or highway financed in whole or in part with federal funds and with respect to which the commissioner of transportation acts as the agent for a political subdivision of the state and is required to approve plans and specifications with respect thereto and to award such contract, the commissioner of transportation shall incorporate into the specifications a provision requiring the same wage rates for labor as is currently used by the state of Minnesota on state trunk highway projects other than interstate projects, for work in the same wage rate area. The provisions of this section shall not be applicable to contracts with any railroad or public utility for the alteration or relocation of any facilities of any such railroad or public utility when the work provided for in said contract is done by the regularly employed forces of said railroad or public utility.