Neb. Rev. Stat. § 39-812
The county board of each county in the state shall have power and is hereby authorized to make annual contracts, which contracts may be made after July 1 of any year and cover the fiscal year of the county, for the construction and erection of the superstructure, the substructure and approaches of all bridges, and for furnishing the materials in connection with the same, to be built within their respective counties for the period of one year, at a specified sum per lineal foot for the superstructure of all such bridges; at a specified sum per lineal foot for the superstructure of all such approaches; at a specified sum per lineal foot for all piling used in the substructure of all bridges and approaches; and at a specified sum per foot, board measure, for all caps, sway braces, and other wood materials used in the substructure of such bridges and approaches.
Neb. Rev. Stat. § 39-812