Ariz. Rev. Stat. § 48-3623
Any bond issued under this article may be refunded pursuant to resolution adopted by the board of directors in the manner provided in this article for the issuance of other bonds, except that an engineer's report or hearing need not be obtained or held, and it is not necessary to submit the question of the issuance of the refunding bonds at an election. Refunding bonds so authorized may be sold and the proceeds of sale applied to or escrowed for the payment of the bonds to be refunded in such manner as may be provided in the authorizing resolution, or may be delivered in exchange for the bonds to be refunded, or may be in part sold and in part exchanged. No bonds may be refunded under this section unless they either mature or are recallable for redemption under their terms within twelve months from the date of the issuance of the refunding bonds or unless the holders voluntarily surrender them for exchange or payment.
A.R.S. § 48-3623