2005 California Government Code Sections 29501 Article 9. Borrowing from Funds

29501.  Whenever the principal or interest on any bonds legally
issued by the county or any district within the county which becomes
due and there is not sufficient money in the fund established for the
payment of the principal or interest to pay it, the board of
supervisors may order the amount of money necessary to pay the
principal or interest, or both, to be transferred from the general
fund to the debt service fund provided for the payment of such
principal and interest pending the collection of any taxes or ad
valorem assessment which have been levied for that purpose.
   The amount transferred is a loan to the fund, and the auditor
shall retransfer it to the general fund not later than the
apportionment of the second installment of taxes collected on the
current secured roll.  The board shall not advance to any debt
service fund an amount greater than the amount of uncollected taxes
or ad valorem assessments levied for the payment of the principal and
interest on the bonds.