Cal. Gov. Code § 15840
The board may provide, by resolution, for the issuance of refunding bonds for the purpose of refunding any bonds of the board issued pursuant to this part and then outstanding, either by voluntary exchange with the holders of the outstanding bonds, or to provide funds to redeem and retire the outstanding bonds, with accrued interest, and any premium payable on the bond at maturity or at any call date. The issuance of the refunding bonds, the maturities and other details of the bonds, the rights of the bondholders, and the duties of the board in respect to the bonds, are governed by the foregoing provisions of this part insofar as they are applicable. Refunding bonds may be issued by the board to refund bonds originally issued, or to refund bonds of the board previously issued for refunding purposes.
Ca. Gov. Code § 15840