Neb. Rev. Stat. §§ 31-374
The bonds so issued shall have recited therein the object of the issue, the title of the article under which the issue was made, stating the issue to be made in pursuance thereof, and shall also state the number, date, and amount of the bonds for which such issue is substituted and amount of the delinquent interest, if any. Such new bonds shall not be delivered until the surrender of the bond or bonds so designated, and they shall be paid and levy made and taxes collected for their payment in accordance with laws now governing the bonds heretofore issued under the provisions of sections 31-301 to 31-369. The assessment of benefits conferred and taxes levied by any such drainage district under the provisions of said sections shall remain valid and binding obligations upon the several tracts of land, but the time of payment of such taxes shall be extended to the same extent as the time of payment of the bonds refunded is extended by the issuing of such refunding bonds, and collection of such taxes shall be made as provided in said sections. The board of supervisors shall issue and file, with the county clerk of the county in which the drainage district was organized, a new certificate of levy of taxes, showing the changed dates when such taxes shall become due, otherwise in the same form and containing the same matter as in the certificate required to be issued by section 31-331, and such taxes shall be used to pay the principal of and the interest on said bonds as the same become due.
Neb. Rev. Stat. §§ 31-374