Whenever the traffic committee has designated and described any street or portion thereof as a through street or any intersection at which vehicles are required to stop at one or more entrances thereto, or any railroad grade crossing at which vehicles are required to stop, the city traffic engineer shall erect and maintain stop signs as follows:

A stop sign shall be erected on each and every street intersecting such through street or portion thereof so designated and at those entrances to other intersections where a stop is required and at any railroad grade crossing so designated; provided however, stop signs shall not be erected or maintained at any entrance to an intersection when such entrance is controlled by an official traffic-control signal. Every such sign shall conform with, and shall be placed as provided in, the Vehicle code (Ord. 858 NCS §1; prior code § 15.7.)