Protected areas and spacing of signs adjacent to interstate and limited access primary highways

highways No signs except as otherwise permitted herein will be allowed within six hundred and sixty feet of the nearest edge of the right-of-way except in areas zoned industrial or commercial and in actual use as such as determined by the commissioner of transportation or which is an unzoned industrial or commercial area as defined in section 13a-123-2. Signs in zoned industrial or commercial areas in actual use and in unzoned industrial or commercial areas which are permitted shall be subject to the following spacing requirements and be consistent with the applicable provisions of this section and sections 13a-123-4 and 13a-123-13. (a) Spacing between sign structures along each side of the highway shall be a minimum of five hundred feet except that this spacing shall not apply to signs which are separated by a building or other obstruction in such a manner that only one sign located within the minimum spacing distance set forth above is visible from the highway at any one time. (b) Sign structures may not be located within five hundred feet of an interchange or rest area measured along the interstate or limited access primary highway from the sign to the nearest point of the beginning or ending of pavement widening at the exit from or entrance to the main traveled way. In any case where ramps exist only on one side of the roadway crossed by the above-mentioned highways, the five hundred foot distance shall also be measured from the centerline of the intersected roadway in the opposite direction from the ramps. The distance requirement from an interchange or rest area set forth above shall not apply within the boundaries of a municipality with a population of forty thousand or more according to the 1960 federal census if the state deems such to be consistent with customary use in the area.