Neb. Rev. Stat. §§ 18-410
Any metropolitan utilities district is hereby given power to extend water mains, gas mains, and other utility service under its operation and management beyond the corporate limits of the city of the metropolitan class so as to include adjacent territory, sanitary and improvement districts, unincorporated areas, cities, or villages, even though in an adjoining county or counties, and may create such water main districts, gas main districts, sanitary sewer districts, storm water disposal districts, and other public utility districts within such adjacent sanitary and improvement districts, unincorporated areas, cities, and villages, even though located in an adjoining county or counties. When such water main districts, gas main districts, sanitary sewer districts, storm water disposal districts, or other public utility districts are created in an adjoining county or counties, the special assessment levy in such districts shall be certified to the county treasurer of such adjoining county or counties, as the case may be, and shall there be entered of record against the proper real estate. It shall be the duty of the county treasurer of the adjoining county or counties, as the case may be, to collect the assessments and as collected to report and transmit such assessments to the metropolitan utilities district.
Neb. Rev. Stat. §§ 18-410