(a) A district shall establish and maintain reasonable and nondiscriminatory rates or other compensation for the use of the facilities of the system acquired, constructed, operated, regulated, or maintained by the district.
(b) Together with grants received by the district, the rates or other compensation must be sufficient to produce revenue adequate to:
(1) pay all expenses necessary for the operation and maintenance of the district’s property and facilities;
(2) pay the principal of and interest on bonds issued by the district payable wholly or partly from the revenue, as they become due and payable; and
(3) fulfill the terms of agreements made with the holders of bonds or with any person on their behalf.