N.D. Cent. Code § 61-24.8-39
Any district having outstanding special assessment bonds, payable in whole or in part out of collections from special assessments, which are past-due or which are redeemable, either at the option of the district or with the consent of the bondholders, may issue refunding special assessment bonds if there is not sufficient money in the project fund against which such bonds are drawn to pay the same. The issuance of refunding bonds must be authorized by resolution of the board. The resolution must describe the bonds to be refunded and their amount and maturity. Refunding bonds may be issued to extend the maturities of bonds payable in whole or in part by special assessments or to reduce the interest on the bonds. Refunding bonds must bear such date, be in such date, be in such denominations, and mature serially within such time, not exceeding thirty years from date of issuance, as the board determines. The treasurer of the district shall pay special assessment bonds as they mature and are presented for payment out of the fund against which they are drawn and shall cancel the bonds when paid.
N.D.C.C. § 61-24.8-39