If two (2) or more railroads, interurban street railroads, or suburban street railroads are located in proximity to each other as to be involved in a single separation of grades, the utility regulatory commission shall pay the half of the cost not paid by the department, apportioned between the railroads, interurban street railroads, or suburban street railroads in proportion as the cost of the separation has been enhanced by the presence of the respective railroads, interurban street railroads, or suburban street railroads.
IC 8-23-9-43