California Code, Water Code - WAT § 52757

The board may, by resolution adopted prior to the time of issuing any refunding bonds, provide for the call and redemption thereof, in numerical order, or by lot, as prescribed in the resolution, on any interest payment date prior to their fixed maturity, at not exceeding the par value thereof and accrued interest, in which event a statement to that effect shall appear on the face of the refunding bond.