Cal. Water Code § 53042.5

Time warrants may be issued for more than the amount set forth in Section 53042 and with a maturity longer than five years, provided that a special election is held pursuant to Chapter 3 (commencing with Section 50800) of Part 4 of this division, at which election the principal amount and maturity of such warrants and the purpose for which they are issued are approved by a majority of the votes cast.