Cal. Wat. Code § 35554
An alternative to, and in addition to, other methods contained in this division regarding the apportionment of water, the district may enter into long-term water service contracts with the holders of title to land for the apportionment of all or any part of its water supply. Long-term water service contracts may provide that all water charges provided for, when due, are a lien on the land in the nature of assessments and may be collected and enforced in the manner provided in this division for the collection and enforcement of assessments. Any such lien shall have the same force, effect, and priority as an assessment lien if the contract is recorded in the office of the county recorder in the county in which the land is situated.
Ca. Water Code § 35554