Except on such streets that form a part of the route of a primary or secondary state highway upon which the state law requires the State Highway Commission to install, operate, maintain, and control traffic-control devices, whenever any city ordinance designates and describes an arterial highway, it shall be the duty of the street superintendent to place and maintain a stop sign on each and every street intersecting such arterial highway or intersecting that portion thereof described and designated as such by any city ordinance. (Ord. 282 § 35, 1968).