(a) Such sewage system commissioners shall have the supervision of such municipal sewage system and shall make and establish all needed rates for rent, with rules and regulations for its control and operation. Such commissioners may appoint or remove a superintendent at their pleasure. The rents and receipts for the use of such sewage system shall be used and applied to pay the interest and principal of the sewage system bonds of such municipal corporation, the expense of maintenance and operation of the sewage system, as well as dedicated fund payments provided for in section 3616 of this title.(b) When a rate established under this section for the management of stormwater is applied to property owned, controlled, or managed by the Agency of Transportation, the rate shall not exceed the highest rate category applicable to other properties in the municipality, and the Agency of Transportation shall receive a 35 percent credit on the rate. The Agency of Transportation shall receive no other credit on the rate from the municipal corporation.Amended 1989, No. 45, § 2; 2015, No. 158 (Adj. Sess.), § 30, eff. 6/2/2016.