Neb. Rev. Stat. § 39-1341

The governing body of any political or governmental subdivision or public corporation may enter into a written agreement with the department for the maintenance of the additional width, as provided for in section 39-1305 , by the department and from time to time, in accordance with such agreement, shall appropriate and pay into the Highway Cash Fund such sums of money as may be agreed upon. Nothing contained in this section shall be construed to prevent any political or governmental subdivision or public corporation from maintaining such additional width at its own expense.