California Code, Public Utilities Code - PUC § 33010

The board may provide for the issuance, sale, or exchange of refunding bonds to redeem or retire any bonds issued by the district under this chapter upon the terms, at the times, and in the manner that it determines. Refunding bonds may be issued in a principal amount sufficient to pay all, or any part, of the principal of the outstanding bonds issued under this chapter, the interest thereon, and the premiums, if any, due upon call and redemption thereof prior to maturity and all expenses of the refunding.

The provisions of this chapter, for the issuance and sale of bonds apply to the issuance and sale of refunding bonds, except that, when refunding bonds are to be exchanged for outstanding bonds, the method of exchange shall be as determined by the board.