Where navigable waters mark the dividing line between two or more counties and the respective boards of chosen freeholders thereof have or shall have resolved that a bridge across such waters at any point or between any points, is a public necessity, such boards respectively may authorize the making of preliminary examinations, surveys, drawings, soundings and the securing of preliminary estimates of the cost of construction of a bridge and its approaches.

Each board may appropriate an amount not exceeding five thousand dollars, which, together with the amount hereinafter appropriated to be paid by the state through the state highway commissioner, shall be used to pay the cost of the preliminary examinations, surveys, drawings, soundings and securing of preliminary estimates of the cost and expense of erecting and maintaining any such bridge and approaches.