The expense of construction and the maintenance of public highway grade crossings shall be borne by the railroad or railway company involved. For overgrade or undergrade public highway crossings over or under steam or electric railroad or railway, the assignment of cost and maintenance shall be left to the discretion of the Corporation Commission; but in no event shall the city, town or municipality be assessed with more than fifty percent (50%) of the actual costs of such overgrade or undergrade crossings.
Okla. Stat. tit. 17, § 82