In case the public highways shall be benefited by the construction of such proposed ditch or ditches, drain or drains, the appraisers shall determine as nearly as may be the amount of such benefits so accruing to the township or county, as the case may be, and said township or county shall pay such pro rata share of the costs and expenses of the construction of the ditch or ditches, drain or drains.
Neb. Rev. Stat. §§ 31-212