OBLIGATIONS.

(a) A public utility agency may:

(1) issue obligations, including anticipation notes, to accomplish the purposes of the agency; and

(2) finance or refund the acquisition, construction, expansion, and improvement of all or a portion of a facility relating to an agency purpose.

(b) Except as provided by Subsection (b-1), the public utility agency may pledge to the payment of the obligations:

(1) the revenue of all or part of its facilities, including facilities acquired after the obligations are issued;

(2) revenues received from a public entity by contract as authorized by a concurrent ordinance;

(3) special assessments imposed by a public entity and provided by contract to the agency; or

(4) any other funds of the agency.

(b-1) Operation and maintenance expenses, including salaries and labor, materials, and repairs of facilities necessary to render efficient service, are a first lien on and charge against the pledged revenue.

(b-2) A public utility agency may not use a facility owned by the agency to secure or collateralize a new facility without the approval by resolution of each participating public entity participating in the joint financing of the new facility. This subsection does not apply to the use of revenue from a facility owned by the agency to secure or collateralize a new facility.

(c) The public utility agency may set aside from the proceeds of the sale of the obligations amounts for payment into the interest and sinking fund and reserve fund, and for interest and operating expenses during construction and development, as specified in the proceedings authorizing the obligations.

(d) Obligation proceeds may be invested, pending their use, in securities, interest-bearing certificates, or time deposits as specified in the proceedings authorizing the obligations.