70 ILCS 1250/4

Upon the completion of any such extension of such boulevard or driveway the title thereto, and to the bed thereof, shall be vested in such board of park commissioners for the purpose of a boulevard or driveway, and shall become a part of the public park or parks under the control of such board, and shall thenceforth be maintained and controlled by such board in the manner provided by law for the government and maintenance of other boulevards and driveways under its control.