Neb. Rev. Stat. §§ 70-644
No power plant, system, or irrigation works owned by a district shall be sold, alienated or mortgaged by such district, except under the circumstances set forth in this section and sections 70-645 to 70-653.02. If, in order to borrow money from the federal government, the Rural Electrification Administration, the Public Works Administration, from any loan or finance corporation or agency established under federal law, including the Reconstruction Finance Corporation, or its successor, or a cooperative nonprofit corporation organized to provide financing, it shall become necessary that a district mortgage, or otherwise hypothecate, any or all of its property or assets to secure the payment of a loan or loans made to it by or from such source or sources, such district is hereby authorized and empowered to do so.
Neb. Rev. Stat. §§ 70-644