The department of behavioral healthcare, developmental disabilities and hospitals shall have the management, supervision, and control of both the Eleanor Slater hospital and the Rhode Island state psychiatric hospital, and such other functions as have been or may be assigned. The director of the department may delegate to another employee of the department any functions related to the separate management, supervision, and control of the state-operated hospitals. The department also shall operate, maintain, and repair the buildings, grounds, and other physical property at those institutions, other than the roads and driveways, which shall be under the care and supervision of the department of transportation.