Upon receipt of such request in the form provided for from at least three of the counties, the commission is authorized and empowered to proceed with the construction of the bridge or tunnel in accordance with and subject to such limitations or restrictions as the governing bodies of the counties may prescribe. The commission, in conjunction with a similar body appointed by the state, county or municipality with which the bridge or tunnel will connect, or with such state, county or municipality, may enter into the necessary contracts for the erection, equipment and operation of the bridge or tunnel.