Neb. Rev. Stat. §§ 15-717
The city council of a city of the primary class shall have the power to lay off the city into suitable districts for the purpose of establishing a system of sewerage and drainage, to provide such system and regulate the construction, repairs, and use of sewers and drains, and to provide penalties for any obstruction of, or injury to, any sewers or drains and for any violation of the rules and regulations with respect thereto that may be prescribed by the city council. The city council shall have the power to create sewer districts by ordinance and designate the property to be benefited by the construction of sewers in such districts. The city council shall have the power to construct or cause to be constructed such sewer or sewers in such district or districts and assess the cost thereof against the property in such districts, to the extent of the special benefits.
Neb. Rev. Stat. §§ 15-717