Cal. Sts. & High. Code § 5898.28

A public agency may issue bonds pursuant to this chapter, the principal and interest for which would be repaid by voluntary contractual assessments. A public agency may advance its own funds to finance work to be repaid through voluntary contractual assessments, and may from time to time sell bonds to reimburse itself for such advances. A public agency may enter into a relationship with an underwriter or financial institution that would allow the sequential issuance of a series of bonds, each bond being issued as the need arose to finance work to be repaid through voluntary contractual assessments. The interest rate of each bond may be determined by an appropriate index, but shall be fixed at the time each bond is issued. Bond proceeds may be used to establish a reserve fund, and to pay for expenses incidental to the issuance and sale of the bonds. Division 10 (commencing with Section 8500) shall apply to any bonds issued pursuant to this section, insofar as that division is not in conflict with this chapter.