Cal. Streets and Highways Code § 5832.6

If a maintenance district is organized in any year too late for the levy of a special assessment tax or an assessment, as the case may be, in that year or in the next ensuing year, the board of supervisors is hereby authorized to transfer funds of the county not immediately needed for county purposes to the maintenance district fund of the district to be used for the payment of the expenses of the district until such time as special assessment tax or assessment, as the case may be, receipts are available therefor. The board of supervisors shall include in the levy of special assessment taxes or assessments for the district for the first fiscal year in which a tax or an assessment may be levied, a sum sufficient to repay to the county the amounts so transferred to the district for the portion or portions of the preceding fiscal year or years for which no levy of taxes or assessments was made for that purpose and the amounts so transferred shall be retransferred to the county treasury from the maintenance district fund of the district out of the first available receipts from the tax or assessment levy.