In the event the required subdivision improvements are financed and installed pursuant to special assessment proceedings, the subdivider may apply to the city council for a reduction in the amount of the improvement security required under this chapter up to an amount corresponding to the amount of faithful performance and payment bonds required of the contractor by the special assessment act being used. The city council may grant the reduction if it finds that the bonds have been in fact provided and that the obligations secured thereby are substantially equivalent to that required by this title. (Ord. 90-1 (part), 1990)