In any local improvement district upon the written request of the contractor the city clerk shall not later than the twenty-fifth day of the following month deliver to the contractor money or warrants in an amount equal to eighty-five percent of such estimate issued by the commissioner of public works as provided in Section 13.48.160 of this chapter. In ease warrants are issued they shall be drawn against the local improvement district fund under which the work is being done and shall bear interest at the rate of four percent per annum from date to the time fixed in the proposal for the completion of the contract, plus not to exceed one hundred eighty days allowed for the approval of the assessment roll and issue of bonds, beyond which the city shall not allow interest. Said warrants shall be redeemed either in cash or by local improvement bonds authorized to be issued in said local improvement district. This section shall apply to all local improvements where the district has heretofore been created but for which no advance warrants have been issued prior to the effective date of this chapter, and any improvement hereafter provided for in any local improvement district. This chapter shall not apply to local improvement districts heretofore formed where advance warrants have been all or partially issued. (Prior code § 13.48.190.)