A.  The provisions of this chapter shall not become effective until appropriate signs giving notice of the prima facie speed limits are erected on the road within the limits specifically designated in this chapter in each particular instance.

    B.  It is hereby made the duty of the city engineer with the assistance of the director of public works to erect appropriate signs giving notice of the speed limits upon portions of public roads

designated in this chapter.   (Ord. 486 § 4 (part), 1992:  prior code § 13-11.070)