309.68  Intercounty highways.
  Boards of supervisors of adjoining counties in this state shall:
  1.  Make proper connections between roads which cross county lines and which afford continuous lines of travel.
  2.  Adopt plans and specifications for road, bridge, and culvert construction, reconstruction, and repairs upon highways along and across county boundary lines, and make an equitable division between counties of the cost and work attending the execution of the plans and specifications.
  3.  Make joint agreements for the location, construction, and maintenance of roads under their jurisdiction wholly within one county to provide road access to lands in an adjoining county, when the location provides the most economical and practical method of providing road access. The expense of constructing and maintaining the road shall be equitably shared by the counties in a proportion as the boards may determine.
[C24, 27, 31, 35, 39, §4661; C46, 50, 54, 58, 62, 66, 71, 73, 75, 77, 79, 81, §309.68; 82 Acts, ch 1110, §3]