All functions, services, and duties of the department of behavioral healthcare, developmental disabilities and hospitals shall be organized by the director with the approval of the governor as to:
(1) Division of behavioral health care which includes the program areas of integrated mental health services and substance abuse treatment and prevention services;
(2) Division of hospitals and community rehabilitation services to include the Zambarano unit, the Cranston unit, and the adult psychiatric services unit of the Eleanor Slater Hospital;
(3) Division of developmental disabilities; and
(4) Management services to include all management, financial, and other services necessary to ensure the proper operation of the department.