The department of public health and human services shall use to maximum efficiency the resources of state government in a coordinated effort to: (1) develop and maintain comprehensive services and programs in the fields of: (a) mental health; and (b) chemical dependency; (2) provide, according to the requirements of Title 53, chapter 20, inpatient institutional care for persons with developmental disabilities who require institutional care; and (3) provide nursing home care for honorably discharged veterans as provided by law.