Neb. Rev. Stat. § 14-527

Bonds of a city of the metropolitan class shall not be issued without a vote of the electors in the manner provided for in sections 14-101 to 14-2004 except to finance the following which may be issued by the city council without such vote: (1) Street improvements, grading, renewal, or refunding; (2) police stations, not to exceed one hundred thousand dollars in any one year; (3) parks, not to exceed one hundred thousand dollars in any one year; (4) sewers, not to exceed five hundred thousand dollars in any one year; (5) public comfort stations, not to exceed fifty thousand dollars in any one year; (6) fire stations, not to exceed thirty thousand dollars in any one year; and (7) acquisition of existing utility systems or plants by condemnation proceedings.