Mo. Rev. Stat. § 234.070: Construction of bridge in adjoining county.

Whenever the county commission of any county, upon investigation, shall be satisfied that the citizens of said county will be benefitted by the construction of a bridge in an adjoining county and within one mile of the boundary line dividing said counties, the aforesaid county commission may unite with the county commission of said adjoining county in causing said bridge to be built and may contribute to the expense of building said bridge in any sum not to exceed one-half the cost of such bridge, and may make an appropriation for the payment of same.