The said commission be, and it is hereby, authorized and empowered to lease real estate owned by it, and which, in its judgment, is not necessary for the maintenance and operation of the bridges under its control and jurisdiction, and to grant licenses to public utility companies for the occupation of parts of bridges and other real estate now or hereafter under the control and jurisdiction of said commission, upon such terms and conditions, and for such rentals and fees, as are, in the opinion of the commission, proper and reasonable.
36 P.S. § 3227