Cal. Wat. Code § 75090
The bonded indebtedness of an improvement district formed pursuant to this chapter may be made payable from assessments to be levied upon all real property in the improvement district by proceedings taken in the manner provided in this article and shall be so payable if the proceedings for the formation of the district so require.
In either case, the petition for the formation of the improvement district, the notice of hearing, the resolution calling the bond election, and the notice of the bond election shall contain a statement that any bonds authorized to be issued by the improvement district shall be payable, both principal and interest, from assessments to be levied upon all real property in the improvement district as finally formed.
If the bonds then receive the vote required under Section 75065, all the bonds shall be payable solely from assessments levied upon all real property in the improvement district, and all such real property therein shall be liable to be taxed for the purpose of paying principal and interest of such bonds.
Ca. Water Code § 75090