A user of property connected to the public storm drainage system shall pay a monthly surcharge determined by the council to be an equitable share of the city’s actual cost of operating and maintaining the system. The surcharge shall be in addition to and not in lieu of any similar charge imposed by any other public entity for operation and maintenance of a similar system. [BC 4.06.020, added by Ordinance No. 3687, 7/17/89; amended by Ordinance No. 3933, 6/26/95]