Neb. Rev. Stat. § 70-629

Except for the authority to make assessments granted by section 70-667 to districts organized under or subject to Chapter 70, article 6, the district shall have no power of taxation, and no governmental authority shall have the power to levy or collect taxes for the purpose of paying, in whole or in part, any indebtedness or obligation of or incurred by the district or upon which the district may be or become in any manner liable.