(a) The board may issue refunding bonds of the district to refund any outstanding district bonds and accrued interest on those bonds.
(b) Refunding bonds may:
(1) as to outstanding bonds payable wholly from taxes, be issued to refund more than one series or issue of the outstanding bonds; and
(2) as to outstanding bonds payable wholly or partly from net revenue:
(A) be issued to refund more than one series or issue of the outstanding bonds;
(B) combine the pledges for the outstanding bonds for the security of the refunding bonds; and
(C) be secured by other or additional revenue.

(c) Bonds payable solely from net revenue may not be refunded into bonds secured by taxes unless the issuance of the bonds is authorized by a majority of the voters voting at an election held in the same manner as a bond election.
(d) Refunding under this section may not impair the contract rights of the holders of any of the outstanding bonds that are not to be refunded.
(e) Refunding bonds must:
(1) be authorized by a board resolution or order;
(2) be executed and mature as provided by this chapter for original bonds; and
(3) bear interest at the same or a lower rate than that of the bonds refunded unless it is shown mathematically that a saving will result in the total amount of interest to be paid.
(f) The comptroller shall register the refunding bonds on surrender and cancellation of the bonds to be refunded.
(g) Instead of issuing bonds to be registered on the surrender and cancellation of the bonds to be refunded, the district, in the resolution or order authorizing the issuance of the refunding bonds, may provide for the sale of the refunding bonds and the deposit of the proceeds in the place or places at which the bonds to be refunded are payable. In that case, the refunding bonds may be issued in an amount sufficient to pay the interest on the bonds to be refunded to their option date or maturity date, and the comptroller shall register the refunding bonds without the surrender and cancellation of the bonds to be refunded.