The board of supervisors may require in the contract that upon the effective date of the contract, the district officers shall continue to perform all the duties relative to the collection of district assessments, including delinquent assessments, levied prior to the effective date of the contract, the enforcement of their payment, and the sale of property for nonpayment and redemption from sale pursuant to the laws in force in the district at such effective date.
Ca. Water Code § 26604.6