Cal. Water Code § 46381

A district may issue direct assessment warrants payable from the proceeds of an interim project assessment pursuant to Chapter 7 (commencing with Section 45900) of Part 8 of this division, but such warrants shall be made payable not more than five years from the date of issuance and may be made subject to call or redemption prior to their stated maturity date or dates at such premium, if any, as the board may determine, and the aggregate face amount thereof shall not exceed seventy-five percent (75%) of the amount of the interim project assessment from which such warrants are payable, exclusive of interest and amounts paid prior to the issuance of such warrants on said interim project assessment.