(a) A public utility agency may not engage in any utility business other than the collection, transportation, treatment, or disposal of sewage or the conservation, storage, transportation, treatment, or distribution of water for a participating public entity that owns jointly with the agency a facility in this state.
(b) A public utility agency may:
(1) perform any act necessary to the full exercise of the agency’s powers;
(2) enter into a contract, lease, or agreement with or accept a grant or loan from a:
(A) department or agency of the United States;
(B) department, agency, or municipality or other political subdivision of this state; or
(C) public or private corporation or person;
(3) sell, lease, convey, or otherwise dispose of any right, interest, or property the agency considers to be unnecessary for the efficient operation or maintenance of its facilities; and
(4) adopt rules to govern the operation of the agency and its employees, facilities, and service.