(1) Whenever the board of supervisors of any county finds that any public road, bridge, or causeway located in a contiguous county and leading therefrom and into that county is not properly worked or is not kept in good repair by the county in which same is located, and finds that its own county would be benefited by the proper working and repairing of such public road, bridge, or causeway, then in such event the board of supervisors of the county which would be benefited is authorized and empowered, in its discretion, to cause to be constructed, improved, worked, repaired, and maintained, at the expense of the county which would be benefited, any such public road, bridge, or causeway for a distance not exceeding three and one-half miles beyond the line of the county which would be benefited, provided that the board of supervisors of the county in which such public road, bridge, or causeway is located shall consent thereto. The board of supervisors of any county which would be benefited is authorized and empowered, for and in the name of such county, to make all necessary contracts for the construction, improving, working, repairing, or maintaining of such public road, bridge, or causeway as herein provided, and to pay for the same either out of the general funds of the benefited county or out of the proceeds of the bonds of such benefited county, issued as otherwise provided by law, either for such purpose or for such purpose and any other lawful purpose. In instances where one or more, or parts of one or more, townships of any county are cut off from convenient communication with the county seat of last said county, either by the interposition of the territory of a contiguous county or by a watercourse or other body of water or by both, then the board of supervisors of the county which would be benefited or whose communication with its county seat is so obstructed or interfered with as aforesaid may, at its discretion and with the consent of the board of supervisors of such contiguous county, lay out, open, construct, improve, work, repair, and maintain, or construct, improve, work, repair, or maintain if already laid out, opened, or established, as much as three and one-half miles in length of road in or through a contiguous county, and pay for the same as hereinabove provided.

(2) Whenever the board of supervisors of any county finds by order or resolution entered upon its minutes that it is to the best interest of the citizens of said county for it so to do, that a public necessity therefor exists, and that said county would be benefited thereby, it is authorized and empowered in its discretion to cause to be constructed or reconstructed, at the expense of such county, such portion as it may elect of any public road lying in a contiguous county which extends from the county line of such county into such contiguous county, together with one or more connecting roads leading therefrom located in the contiguous county. The construction or reconstruction of the public road lying in a contiguous county which extends from the county line of such county into such contiguous county may be paid for out of county road funds, state aid road funds, or such other funds as may be available therefor. However, state aid road funds shall not be used to construct or reconstruct any connecting road located in the contiguous county, and the county constructing or reconstructing said connecting roads may pay therefor only from county road funds or such funds as may be available therefor other than state aid road funds. In the event state aid funds are used in connection with the exercise of the power and authority granted in this subsection, the state aid engineer’s duties, responsibilities, and authority with respect thereto shall be the same as that provided by the law governing state aid projects.

Before exercising any rights or authority granted in this subsection, the board of supervisors of the county proposing to take advantage of the authority herein contained shall secure the consent of the board of supervisors of the contiguous county, which consent shall be evidenced by an order or resolution of the board of supervisors of the contiguous county and spread upon its minutes.

(3) The boards of supervisors of any two adjoining counties may, by an agreement spread upon the minutes of the board of each of such counties, join together in the construction, reconstruction, improvement, working, repair, or maintenance of any public road, bridge, or causeway, including the approaches to such bridge or causeway, located partly in each of such counties, or benefiting each of such counties, for a distance of not exceeding three and one-half miles beyond the county line in either of such counties, and may jointly perform such work or jointly award contracts therefor and jointly pay the cost thereof, as provided in said agreement between said boards, from funds authorized by law for roads, bridges, or causeways located entirely within either of such counties. Such an agreement may be terminated in whole or in part by a succeeding board of supervisors of either of such counties, provided, however, that each of such counties shall remain obligated to pay its respective part of any outstanding obligations connected with or arising from said joint project. Unless the board of each county agrees otherwise, upon termination of such an agreement the responsibilities of future construction, reconstruction, improvement, working, repair, or maintenance on such road, bridge, or causeway shall be that of the county in which the respective parts thereof are located.