Neb. Rev. Stat. §§ 2-3254.05
The proceeds of all special assessments for an improvement project area shall constitute a sinking fund for the purposes of paying the cost of the special benefit portion of the project and for paying warrants and bonds issued pursuant to sections 2-3252 and 2-3254.01 to 2-3254.07 and shall, together with the interest payable upon such special assessments, be set aside and used to pay such costs, bonds, and warrants. Any money remaining in the sinking fund after fully discharging such costs, bonds, and warrants may be applied by the board for operation and maintenance expenses relating to such project or may be transferred to the general fund of the district. In any resolution authorizing the issuance of bonds or warrants, the board may provide that general funds of the district, including the proceeds from such district's tax levied pursuant to section 2-3225, shall be transferred and paid into the sinking fund to provide for the prompt payment of principal and interest on any bonds and warrants of the district which are to be paid from such sinking fund, as they become due.
Neb. Rev. Stat. §§ 2-3254.05