(a) The Commission shall set a service rate that the Commission considers necessary to provide funds for:
(1) maintaining, repairing, and operating its water supply and sewer systems, including the overhead expense and depreciation allowance; and
(2) making any payments to the District of Columbia, as specified in this title.
(b) The service rate:
(1) shall be chargeable against all properties for a connection with any line owned by the Commission;
(2) shall be uniform throughout the sanitary district; and
(3) may be changed as necessary.